# Modern full-range Class D amplifiers



## thereddestdog

One of the first things I noticed while getting gear together after an audio hiatus was that there are a lot of amps out there now that are full range and Class D, which were only recommended for subwoofers in my time.

Now, I'm firmly in the A/B camp, and I'm sure there are a few A fanatics out there still, but how do these new school Class-D amps fair?


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## rob feature

For the most part there don't seem to be many if any disadvantages to Class D anymore when comparing them to A/B. It took me a while to come around but I'm all D now...no regrets.


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## truckerfte

rob feature said:


> It took me a while to come around but I'm all D now...no regrets.


There is a joke in there somewhere......


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## Victor_inox

Not again...

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## brumledb

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## Justin Zazzi

thereddestdog said:


> One of the first things I noticed while getting gear together after an audio hiatus was that there are a lot of amps out there now that are full range and Class D, which were only recommended for subwoofers in my time.
> 
> Now, I'm firmly in the A/B camp, and I'm sure there are a few A fanatics out there still, but how do these new school Class-D amps fair?


This question comes up in one form or another all the time.

Some will argue that tube amps are the only way to go while listening exclusively to vinyl, op-amps are the work of the devil, and digital anything means a "stair-step" signal which cannot possibly ever sound good despite decades upon decades of evidence to the contrary. These folks are like the ones who will insist that crop circles are real even if you show them a video of people making the crop circles with rope and some wood boards.

Many are still afraid of class D for whatever reason and go A or A/B for everything, as if class A has some magical acoustic properties just because it's class A and literally nothing else matters other than the little badge on the side of the amplifier that reads "Class A", similar to how certain teenagers have a stigma where they put specific stickers on their cars in an effort to summon more horsepower.

An enlightened few understand that class D amplifiers have matured tremendously from early models and are generally indistinguishable from any others except they are smaller, generate less heat, consume less power from the battery due to higher efficiency, and many will deliver full power into multiple impedance setups so you don't have to build a 2-ohm or 1-ohm system.

I'm not biased or anything though.


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## Hillbilly SQ

Jazzi said:


> This question comes up in one form or another all the time.
> 
> Some will argue that tube amps are the only way to go while listening exclusively to vinyl, op-amps are the work of the devil, and digital anything means a "stair-step" signal which cannot possibly ever sound good despite decades upon decades of evidence to the contrary. These folks are like the ones who will insist that crop circles are real even if you show them a video of people making the crop circles with rope and some wood boards.
> 
> Many are still afraid of class D for whatever reason and go A or A/B for everything, as if class A has some magical acoustic properties just because it's class A and literally nothing else matters other than the little badge on the side of the amplifier that reads "Class A", similar to how certain teenagers have a stigma where they put specific stickers on their cars in an effort to summon more horsepower.
> 
> An enlightened few understand that class D amplifiers have matured tremendously from early models and are generally indistinguishable from any others except they are smaller, generate less heat, consume less power from the battery due to higher efficiency, and many will deliver full power into multiple impedance setups so you don't have to build a 2-ohm or 1-ohm system.
> 
> I'm not biased or anything though.


This x2. It took me a while to come around but I'll never go back to a/b amps. In most cases class d amps just make more sense in the mobile environment. There are still some turds in the punch bowl when it comes to fullrange d amps but those can be easily avoided by doing a little research before buying


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## Jscoyne2

On this note. I have a Sundown Sax 150.4 Full range class D amplifier that ive been considering selling and getting some Zapco Sq A/B amps with the money. 

Considering Basically power would be the same but topology would be different. Should i just just stay with the sundown?


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## DC/Hertz

Unless you just want the name Zapco keep what you have. 

The way some seem to think is a boss A/B is better then any class D. If you put it in that senerio it becomes quite obvious it's the wrong way to think. 

I'll also never go back to A/B. The power per Sq inch of class D can't be touched.


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## audiocholic

If I kindly asked can you guys please make a list in 2 versions lets say perhaps 1000usd and less and the other list 500usd and less D class amps that you would advise for SQ ?


that way atleast the topic would be alittle helpful/guideful for ones interested in purchasing D class.


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## Hillbilly SQ

I don't know the pricing of the amps out there today but will make some suggestions of known good performers.

All JL fullrange D amps are solid
Alpine PDX
NVX JAD series 
PPI Phantom
Soundstream Turantula Nano
Zapco st-D
There's many more, but my personal favorite are the JL class D amps. I'm not the only one that has said there's just something about the XD amps that makes a system sound a little more magical.


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## DC/Hertz

I'd pick the largest 4 channel powerwise (250x4)which is the same size as others 150x4
Digital Designs SS4B. I have the SS4A but it's only 160x4. 
They go fot $600-$700

For less then that it would be the NVX JAD.


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## AAAAAAA

Only thing with class D that's a negative is interference with radio bands. Often it can make radio reception, if anyone still usestheir radio, awful.


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## rob feature

truckerfte said:


> There is a joke in there somewhere......


:lips::biker::builder2::indian_chief:


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## gijoe

Jscoyne2 said:


> On this note. I have a Sundown Sax 150.4 Full range class D amplifier that ive been considering selling and getting some Zapco Sq A/B amps with the money.
> 
> Considering Basically power would be the same but topology would be different. Should i just just stay with the sundown?


Yes, stick with what you have. Even before class D became a contender fullrange, it dominated as a subwoofer amp. The switching frequency was too low to allow class D to work well full range, but it was still plenty high to have 0 impact at subwoofer frequencies. Switching frequencies of class D have improved drastically, and I would never run an A/B amp in my car ever again. There's just no reason to.


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## mrpeabody

I've been back and forth between the two and decided to go with class D in the car. I dig the small foot print and efficiency.


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## Viggen

Years ago yes, there was a difference but today as many state it's very close and with the much smaller footprint and lower power draw the class D has huge advantages in the Mobil world.

Personally, I wouldn't buy a amp with A vs A/B vs D being the main factor.

Physical size and power restraints and of coarse cost should be the main factors.

I am home amp shopping and will try a class D amp due to the reasons I mentioned above


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## Victor_inox

Viggen said:


> Years ago yes, there was a difference but today as many state it's very close and with the much smaller footprint and lower power draw the class D has huge advantages in the Mobil world.
> 
> Personally, I wouldn't buy a amp with A vs A/B vs D being the main factor.
> 
> Physical size and power restraints and of coarse cost should be the main factors.
> 
> I am home amp shopping and will try a class D amp due to the reasons I mentioned above


with Class V power supplies it will take less then 0.5w on standby.

my heos soundar never switch itself off for that reason alone.


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## Viggen

Yea I have seen that several class D home amps and some do not have auto turn on and pull less then 10w 

I am leaning towards a D-sonic amp, from what I have read really good SQ and they are priced in a affordable price point. Just like in a car.... if I used A or A/B for my home setup, I would need major electrical updates.


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## Victor_inox

Viggen said:


> Yea I have seen that several class D home amps and some do not have auto turn on and pull less then 10w
> 
> I am leaning towards a D-sonic amp, from what I have read really good SQ and they are priced in a affordable price point. Just like in a car.... if I used A or A/B for my home setup, I would need major electrical updates.


I just finished 400W/ch prototype that works better than RAMSA 9220 rated the same power and taking 10.7A from outlet.

My prototype takes 4A or so. 

I`m officially done with class A nonsense. Only for headphones,maybe.

THD at full power 0.00015% beat that AB.


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## DC/Hertz

I was anti D about 8 years ago when I got my first full range. It was the 1st Gen PDX 2.150. It was absolutely a POS. But I came to learn it wasn't a POS because it was D, it was just a POS.


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## Victor_inox

DC/Hertz said:


> I was anti D about 8 years ago when I got my first full range. It was the 1st Gen PDX 2.150. It was absolutely a POS. But I came to learn it wasn't a POS because it was D, it was just a POS.


PDX4.100 I`ve got in 2008 was OK. sold it with a truck.


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## Hillbilly SQ

DC/Hertz said:


> I was anti D about 8 years ago when I got my first full range. It was the 1st Gen PDX 2.150. It was absolutely a POS. But I came to learn it wasn't a POS because it was D, it was just a POS.


I bought a first gen pdx5 off a friend and ran it for a bit on midbass and sub. I ended up selling it back to him several months later. He bought it new when that amp first came out. Fullrange D wasn't quite there yet. It's still alive today. I think it might be in his daughter's truck now.


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## bugsplat

I came from the old days of RF BBQ amps. Worked great and was a firm believer. Bought my first class-D 8'ish years for $30 from some no name place from China. Junk. Couple years ago tried the new Class-D's from some of the big boys and heard no difference between them and the class-A's or AB's I used to run. Tech has caught up with old sound. I run two NVXJAD800's now. I can't imagine going back to the big, heavy, juice sucking models of old. 

Con's of D's for me: 
*They are more susceptible to radio noise. I run headless now so no radio, no problem.
*More susceptible to engine noise. Amp required a dedicated Pos and Neg and a relay on the remote turn-on line. Could have just been my car.


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## Victor_inox

gijoe said:


> Yes, stick with what you have. Even before class D became a contender fullrange, it dominated as a subwoofer amp. The switching frequency was too low to allow class D to work well full range, but it was still plenty high to have 0 impact at subwoofer frequencies. Switching frequencies of class D have improved drastically, and I would never run an A/B amp in my car ever again. There's just no reason to.


 We should setup a demo with my own class D amps at some point.
I have mine switching at 1.2GHz as of today.

IMHO they sound better than just about anything I`ve heard before.

But I`m biased.


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## thereddestdog

Thanks for all the input, really good stuff in here


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## gijoe

Victor_inox said:


> We should setup a demo with my own class D amps at some point.
> I have mine switching at 1.2GHz as of today.
> 
> IMHO they sound better than just about anything I`ve heard before.
> 
> But I`m biased.


That would be fun! I'm afraid I'd end up buying a bunch of stuff that I don't need from you, haha.


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## KillerBox

The Arc Audio xDI amps get high reviews too. Because of this, I bought two of the Arc Audio 1200.6 xDI and getting them installed this week.


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## Victor_inox

gijoe said:


> That would be fun! I'm afraid I'd end up buying a bunch of stuff that I don't need from you, haha.


 Thats a good thing you`ll have something you can`t buy elsewhere and I `ll have funds to make more of that. 
We don`t need anything but food and shelter, everything else we want.

When you can afford "I want it" product is where life began.


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## billj214

NVX dyno results are amazing, price as well! I am running Gladen 5 channel a/b and D for sub (150C5 model) but need more power. Running 2ohm Focal 6.5's which should do much better on a class D amp IMO, is it worth switching amps? JAD800.4 and 1200.1?


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## brianlin87

KillerBox said:


> The Arc Audio xDI amps get high reviews too. Because of this, I bought two of the Arc Audio 1200.6 xDI and getting them installed this week.


Co-sign. I've heard nothing but rave things about the XDi V2 amps, so I just purchased one myself. Looking forward to receiving it. Might have to pair it with another one similar to yourself.


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## stickpony

Hillbilly SQ said:


> This x2. It took me a while to come around but I'll never go back to a/b amps. In most cases class d amps just make more sense in the mobile environment. There are still some turds in the punch bowl when it comes to fullrange d amps but those can be easily avoided by doing a little research before buying




Agreed. They've come a long way. I really like JL Audio's class D amps, very clean sounding. As far as sound quality, they are certainly on par with most high end a/b amps, but IMO, they sound more clinical than A/B amps, more 'dry'. I realize some top end competition cars have used DSPs to overcome these nuances and win top prize. Just goes to show what's good DSP can do


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## DC/Hertz

PHP:




DD is killing the watt per square inch right now.

Edit: I already said this. Forget it, it's worth saying again


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## Victor_inox

AAAAAAA said:


> Only thing with class D that's a negative is interference with radio bands. Often it can make radio reception, if anyone still usestheir radio, awful.


Improperly made that is. Output inductances radiate awful cocktail of frequencies, slightly more expensive inductances/ proper shielding eliminate that problem.


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## Victor_inox

DC/Hertz said:


> PHP:
> 
> 
> 
> 
> DD is killing the watt per square inch right now.
> 
> Edit: I already said this. Forget it, it's worth saying again




why is it square inch and not cubic inch? Or size only matters in 2 dimensions?


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## chuyler1

stickpony said:


> IMO, they sound more clinical than A/B amps, more 'dry'.


This was my take on the Alpine PDX amps when they first hit the market. I heard some systems with amps "just mounted under seats" and I thought they were going to be a joke. I was amazed at the crisp clarity, but the music lacked any sort of naturalness to it, or warmth maybe? 

I know they have come a long way so I'm pretty sure my next install will be with a multi-channel class D and I'll figure out how to tune back in what I might be missing out. 

Not to side track, but another thing that was popular for a while in home audio was those class T amps. How come that architecture hasn't really made it to the main stream car audio brands?


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## AAAAAAA

Victor_inox said:


> Improperly made that is. Output inductances radiate awful cocktail of frequencies, slightly more expensive inductances/ proper shielding eliminate that problem.


There is no way to know before hand how bad EMI is with amps... so it can be a concern.


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## AAAAAAA

Victor_inox said:


> why is it square inch and not cubic inch? Or size only matters in 2 dimensions?


When class D first became mainstream I made a spreadsheet that I shared here comparing volume of different small amps. Indeed some look small until you consider how high they are...


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## DC/Hertz

It's just as high as anything thing else. It's the same dimensions as the PPI 900.4 but it has 100 watts more a channel and it's not Chinese.


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## stickpony

chuyler1 said:


> This was my take on the Alpine PDX amps when they first hit the market. I heard some systems with amps "just mounted under seats" and I thought they were going to be a joke. I was amazed at the crisp clarity, but the music lacked any sort of naturalness to it, or warmth maybe?
> 
> I know they have come a long way so I'm pretty sure my next install will be with a multi-channel class D and I'll figure out how to tune back in what I might be missing out.
> 
> Not to side track, but another thing that was popular for a while in home audio was those class T amps. How come that architecture hasn't really made it to the main stream car audio brands?




Because the company that made the class T chips, 'Tripath' went out of business in 2007, and their intellectual property was bought out by Cirrus Logic, who doesn't have a big stake in car audio.

https://en.m.wikipedia.org/wiki/Class-T_amplifier


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## DC/Hertz

I want to say some of the new Orion amps where marketed class T.. I can't find them now. It may have been BS.


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## chuyler1

stickpony said:


> Because the company that made the class T chips, 'Tripath' went out of business in 2007


Ahh, that explains it. I jump in and out of the hobby every decade or so (like when I start building a new system)...I have some catching up to do.


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## stickpony

chuyler1 said:


> Ahh, that explains it. I jump in and out of the hobby every decade or so (like when I start building a new system)...I have some catching up to do.




Welcome to the club. Same here. 


I would say that an amp is an amp, not all amps are created equal though, just like it always has been. I think the biggest improvements in the mobile audiophile in the last 5 years has been the plethora of reasonably priced DSP solutions, and speaker improvements


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## billj214

chuyler1 said:


> Ahh, that explains it. I jump in and out of the hobby every decade or so (like when I start building a new system)...I have some catching up to do.


Same... Jumped back in after 12 years of stock radios which weren't bad at all (Land Rover and BMW) but now I'm back in a Ford truck with horrible factory system.

Read this forum for the last few months, I've concluded that price does not mean better sound but possibly better build quality unless your talking about speakers where the money is worth every penny! 

I ordered Orion XTR's but the order was canceled due to inventory so I literally spent one more day on research and found a PPI Phantom 900.4 for $100 on Amazon with damaged package and also an open box 1000.1 for $140!! Just saved $200 so I opted to also buy the Toslink adapter for my PAC AP4-FD21 to run to my Helix DSP and still have money in my pocket!


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## Ziggyrama

This thread makes me wonder if I would benefit from upgrading my 1st gen pdx to something like NVX 4 channel amp. The NVX is significantly newer class D amp, but I wonder, would there be an audible difference in sound quality?


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## billj214

Ziggyrama said:


> This thread makes me wonder if I would benefit from upgrading my 1st gen pdx to something like NVX 4 channel amp. The NVX is significantly newer class D amp, but I wonder, would there be an audible difference in sound quality?


I was going to buy NVX but from what I hear they are exactly the same. Dyno results on both from YouTube also show similar numbers. Only reason I opted for PDX is I found it cheap. You could also consider Orion, solid power for cheap but 4 channel is AB. Likely I will upgrade in another year but by that time I'll have a little more experience with everything.

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## chuyler1

So I've been running my NVX MVP4A for a few weeks and it hasn't disappointed me one bit. I'm just running 4" Morel components up front and 6.5" DLS midbasses in the rear of my 85 RX7.

Pros: Cheap. Small. Quick to install since it runs off the factory wiring for the OEM amp and is also about the same size. Sounds just fine and certainly better than the OEM amp. Doesn't affect car lights even though my old RX7 only charges at about 13v. 

Cons: No detents on the adjustment knobs which makes it hard to match crossover points between front and rear. Very little markings on the crossover knob so you basically guess or go by ear. Mine seems to be ignoring the remote turn on so if volume is low on factory head unit it will shut off. Also, getting significant turn off pop...but that could be due to the factory head unit.

Overall:
I am quite amazed this little thing doesn't start to break up or run out of breath at high listening levels. I'd like to try one of the JAD models to see how they compare, but it's hard to beat an amp that tucks into the spot mazda designed for an amp and have it perform this well. If I wanted to get really "authentic" I could probably drop the circuit board right into the OEM amp casing and no one, even the next owner of the vehicle, would know it was upgraded!


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## bbfoto

AAAAAAA said:


> Only thing with class D that's a negative is interference with radio bands. Often it can make radio reception, if anyone still usestheir radio, awful.





Victor_inox said:


> Improperly made that is. Output inductances radiate awful cocktail of frequencies, slightly more expensive inductances/ proper shielding eliminate that problem.


The circuitry in the 2nd Generation Alpine PDX amplifiers actually eliminates nearly all forms of noise from and to the vehicle's electrical system. If you have a problem with tuner noise/interference and/or ignition, alternator, or other vehicle electrical noise, try swapping in one of the 2nd Gen PDX amps and I'll almost guarantee a noise-free system.  This applies to the M12 and F4/F6 amps. Though I have heard of QC/build issues with the M6 mono and V9 5-channel Amps. But the M12 & F4/F6 are rock solid in all regards.



Ziggyrama said:


> This thread makes me wonder if I would benefit from upgrading my 1st gen pdx to something like NVX 4 channel amp. The NVX is significantly newer class D amp, but I wonder, would there be an audible difference in sound quality?





billj214 said:


> I was going to buy NVX but from what I hear they are exactly the same. Dyno results on both from YouTube also show similar numbers. Only reason I opted for PDX is I found it cheap. You could also consider Orion, solid power for cheap but 4 channel is AB. Likely I will upgrade in another year but by that time I'll have a little more experience with everything.


The NVX JAD amps are solid performers, especially at their price points! I've used these in several installs for family and friends. For anyone interested, I have a BNIB NVX JAD 900.5 amp in the classifieds here for $199 shipped.  I was going to use it in my nephew's VW Golf install until his wife totalled his car and his replacement vehicle already had a decent system in it. :surprised:

.


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## Victor_inox

bbfoto said:


> The circuitry in the 2nd Generation Alpine PDX amplifiers actually eliminates nearly all forms of noise from and to the vehicle's electrical system. If you have a problem with tuner noise/interference and/or ignition, alternator, or other vehicle electrical noise, try swapping in one of the 2nd Gen PDX amps and I'll almost guarantee a noise-free system.



Thank you but I never had that problem in the first place, I`ve had PDX in 2008 I fix myself before they implemented same solution in 2nd gen units.


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## bbfoto

Victor_inox said:


> Thank you but I never had that problem in the first place, I`ve had PDX in 2008 I fix myself before they implemented same solution in 2nd gen units.


Well, we all know that you're an eclectic exception to the rule around here, Victor! 

Victor, I'd be interested in purchasing one of your new amplifiers to give it a thorough test in both my home and car audio setups. But know that I'll give it a no-holes-barred, honest review here.  And you would have to agree to let me return the amp and provide me with a refund if it's not my cup o' tea.  ...providing I don't damage it cosmetically or electrically. If it's a solid performer and I like it, I'll be sure to keep it and use it.

.


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## el_bob-o

I ran a couple of Cadence Amadeus amplifiers several years ago when they were current and liked them while they worked. They used Tri-path for full range and worked really well for a year or two. Unfortunately they used poorly built power supplies that seemed to fail regularly across the board and decided it was easier to junk them than repair them.


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## Victor_inox

bbfoto said:


> Well, we all know that you're an eclectic exception to the rule around here, Victor!
> 
> Victor, I'd be interested in purchasing one of your new amplifiers to give it a thorough test in both my home and car audio setups. But know that I'll give it a no-holes-barred, honest review here.  And you would have to agree to let me return the amp and provide me with a refund if it's not my cup o' tea.  ...providing I don't damage it cosmetically or electrically. If it's a solid performer and I like it, I'll be sure to keep it and use it.
> 
> .


 I haven`t seen a single dishonest review around here, have you? 

My email [email protected]
30 day unconditional money back and lifetime warranty, providing you not ****ed it up yourself.  " if i remember correctly you only have one of my power supplies.

Now when we got that out of the water tell me what is that exactly do you want?


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## Ziggyrama

bbfoto said:


> The circuitry in the 2nd Generation Alpine PDX amplifiers actually eliminates nearly all forms of noise from and to the vehicle's electrical system. If you have a problem with tuner noise/interference and/or ignition, alternator, or other vehicle electrical noise, try swapping in one of the 2nd Gen PDX amps and I'll almost guarantee a noise-free system.  This applies to the M12 and F4/F6 amps. Though I have heard of QC/build issues with the M6 mono and V9 5-channel Amps. But the M12 & F4/F6 are rock solid in all regards.
> 
> 
> 
> 
> 
> The NVX JAD amps are solid performers, especially at their price points! I've used these in several installs for family and friends. For anyone interested, I have a BNIB NVX JAD 900.5 amp in the classifieds here for $199 shipped.  I was going to use it in my nephew's VW Golf install until his wife totalled his car and his replacement vehicle already had a decent system in it. :surprised:
> 
> .


So the main question is, other than improved noise supression, anything else that is notably better in the 2nd gen PDX amp vs. 1st gen?
I am a bit cautious of NVX brand, considering price and the fact it is a house brand. More often than not, you get what you pay for. My system doesn't have noise problems and it does sound very clean but I don't have golden ears and don't have a lot of runtime with many other amps so frankly, I may not know how much better an amp can be since I haven't really experienced it. You don't miss something you never had, right? I do like Zapco build quality and I have one of their sub amps but it is a sub amp, not hard to build one that should sound decent. I don't like Zapco sizing, they are big which is an issue for me. Running out of room under the seats.
What do you guys know about NVX 4 channel mini amp? Considering one for experimenting with rear fill, I need 2 more channels and space is a problem for me. Thoughts?

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## billj214

Got my PPI phantom 900.1 and 100.1 installed today, really impressed so far, more power then I needed @ 225w x 4 @ 2 ohms and 725 x 1 @ 2 ohms for subs. Small amps with big power, paid about $140 and $100 each from Amazon open box! I feel like I got a steel of a deal! 

Next build for a buddy will be NVX, I'll have to do a comparison.

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## Jonathan

Victor_inox said:


> We should setup a demo with my own class D amps at some point.
> I have mine switching at 1.2GHz as of today.
> 
> IMHO they sound better than just about anything I`ve heard before.
> 
> But I`m biased.


Self-oscillating or clocked switching frequency?


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## Hillbilly SQ

Ziggyrama said:


> So the main question is, other than improved noise supression, anything else that is notably better in the 2nd gen PDX amp vs. 1st gen?
> I am a bit cautious of NVX brand, considering price and the fact it is a house brand. More often than not, you get what you pay for. My system doesn't have noise problems and it does sound very clean but I don't have golden ears and don't have a lot of runtime with many other amps so frankly, I may not know how much better an amp can be since I haven't really experienced it. You don't miss something you never had, right? I do like Zapco build quality and I have one of their sub amps but it is a sub amp, not hard to build one that should sound decent. I don't like Zapco sizing, they are big which is an issue for me. Running out of room under the seats.
> What do you guys know about NVX 4 channel mini amp? Considering one for experimenting with rear fill, I need 2 more channels and space is a problem for me. Thoughts?
> 
> Sent from my VS986 using Tapatalk


I think the micro amp would be fine for rears. If you do it correctly you'll only be playing the L-R differential at very low volumes to enhance the fronts. I'm using factory d-pillar speakers that are 2.75" iirc. Does fine for what I'm asking of them from 350-5000.


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## benny z

how's this for class d?

https://youtu.be/Q4DT-VCoZDc


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## DC/Hertz

benny z said:


> how's this for class d?
> 
> https://youtu.be/Q4DT-VCoZDc


Yep. Sounds like it's playing.


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## Victor_inox

Look at the power supply in this video! Its HUuuuuuge!
Mine is 1/20 in size, weight and probably has lower voltage ripple on top.

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## benny z

Victor_inox said:


> Look at the piwer supply in this video! Its HUuuuuuge?
> Mine is 1/20 in size weight and probably has lower voltage ripple on top.
> 
> Sent from my SAMSUNG-SM-G925A using Tapatalk


what? everyone doesn't have one?

astron rs-50a - pretty industry standard 50A piece...


----------



## Ziggyrama

Hillbilly SQ said:


> I think the micro amp would be fine for rears. If you do it correctly you'll only be playing the L-R differential at very low volumes to enhance the fronts. I'm using factory d-pillar speakers that are 2.75" iirc. Does fine for what I'm asking of them from 350-5000.


Yup, that is my thinking. I have 2 free channels on my DSP and no rear fill. I need something small that can power the rear speakers to add a bit more ambiance. It doesn't have to be super good, just good enough. The rears are currently wired to run off deck power. They are turned off by fading all the way to the front. I tried introducing the rear by simply fading towards the center but it completely destroys the staging and smears imaging. Moral of the story, I need to run it through my processor and that means 2 more amp channels.

Sent from my VS986 using Tapatalk


----------



## Victor_inox

benny z said:


> what? everyone doesn't have one?
> 
> astron rs-50a - pretty industry standard 50A piece...


 It has been successful seller for the last 2 years or so.not sure about everyone  though. I have plenty in my warehouse. 
we changing industry standards to better standards all the time.
I have 50A version now for half the price of that astron, or third?
Not sure what price of that thing nowadays.


----------



## Victor_inox

Ziggyrama said:


> Yup, that is my thinking. I have 2 free channels on my DSP and no rear fill. I need something small that can power the rear speakers to add a bit more ambiance. It doesn't have to be super good, just good enough. The rears are currently wired to run off deck power. They are turned off by fading all the way to the front. I tried introducing the rear by simply fading towards the center but it completely destroys the staging and smears imaging. Moral of the story, I need to run it through my processor and that means 2 more amp channels.
> 
> Sent from my VS986 using Tapatalk


 You can get something like TPA3116 or TDA7492 based chinese board off ebay, they decent quality and cost very little. Just keep in mind that 12V is very low for them to operate at full potential. THey simply don`t.


----------



## Hillbilly SQ

Ziggyrama said:


> Yup, that is my thinking. I have 2 free channels on my DSP and no rear fill. I need something small that can power the rear speakers to add a bit more ambiance. It doesn't have to be super good, just good enough. The rears are currently wired to run off deck power. They are turned off by fading all the way to the front. I tried introducing the rear by simply fading towards the center but it completely destroys the staging and smears imaging. Moral of the story, I need to run it through my processor and that means 2 more amp channels.
> 
> Sent from my VS986 using Tapatalk


What processor? You may need to twist the negative to the left and right rear together and run the positives to the + and - of the amp to get the l-r differential.


----------



## Ziggyrama

Hillbilly SQ said:


> What processor? You may need to twist the negative to the left and right rear together and run the positives to the + and - of the amp to get the l-r differential.


I am running Zapco Z8.
So now I am realizing that I may not understand what you are saying when you say L-R differential. Forgive my ignorance, can you say a bit more?

Sent from my VS986 using Tapatalk


----------



## Ziggyrama

Victor_inox said:


> You can get something like TPA3116 or TDA7492 based chinese board off ebay, they decent quality and cost very little. Just keep in mind that 12V is very low for them to operate at full potential. THey simply don`t.


Holy cow, that TDA7492 looks like a great candidate for the rear fill project. Plenty of power, reviews are pretty good it is small. One thing, how do you handle power? Is there a power supply for the car or I need to make my own?

Sent from my VS986 using Tapatalk


----------



## Hillbilly SQ

Ziggyrama said:


> I am running Zapco Z8.
> So now I am realizing that I may not understand what you are saying when you say L-R differential. Forgive my ignorance, can you say a bit more?
> 
> Sent from my VS986 using Tapatalk


GlassWolf's Pages
This explains it better than I can. All about tricking the brain into thinking the room is bigger than it really is. I'm delayed 24.58ms on mine. This is why I'm running a separate dsp. Something you could do to get the needed delay if you're running an aftermarket unit is have the rears on separate outputs. You can combine delay between the two and also have ability to fade the rears in and out for desired effect. I have to fire up the laptop to fade mine in and out so once I settle on a tune I'm stuck with it until the next session...I do have 4 presets but they're occupied by "demo tune with rearfill, demo tune without rearfill, phone tune, and daily driving tune (yeah I'm a short stocky guy)"


----------



## Victor_inox

Ziggyrama said:


> Holy cow, that TDA7492 looks like a great candidate for the rear fill project. Plenty of power, reviews are pretty good it is small. One thing, how do you handle power? Is there a power supply for the car or I need to make my own?
> 
> Sent from my VS986 using Tapatalk


You need 24volt for it,its pathetic on 12.
I have one i can sell you for 20 bucks.
Up to 10A and adjustable to 60volt or so.

Sent from my SAMSUNG-SM-G925A using Tapatalk


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## Victor_inox

While you at it I can also sell you TDA7492 board for 10 bucks extra.


----------



## Ziggyrama

Victor_inox said:


> While you at it I can also sell you TDA7492 board for 10 bucks extra.


Thanks, let me think about what I wanna do. Btw, how do you mount the board? So you make a custom enclosure for it and screw it down to something? Got any pics of that?

Sent from my VS986 using Tapatalk


----------



## Victor_inox

Ziggyrama said:


> Thanks, let me think about what I wanna do. Btw, how do you mount the board? So you make a custom enclosure for it and screw it down to something? Got any pics of that?
> 
> Sent from my VS986 using Tapatalk


amp board is size of zippo lighter.power supply is about twice that. You can manufacture your own enclosure or I can make you one in chinese project boxes they sell on ebay by millions. 
Only thing to consider is that your labor is free for you, mine is not. 

Email me for pictures [email protected]


----------



## Victor_inox

Dont freak out how tiny 2x100w and power supply for it is.









Sent from my SAMSUNG-SM-G925A using Tapatalk


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## benny z

Ewweeeee man toes!!!


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## Victor_inox

benny z said:


> Ewweeeee man toes!!!




Nothing ewwwww about my toes.its ****ing spring finally!


Sent from my iPad Pro using Tapatalk Pro


----------



## Ziggyrama

Victor_inox said:


> Dont freak out how tiny 2x100w and power supply for it is.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Sent from my SAMSUNG-SM-G925A using Tapatalk


Wow, that is small. Is that 2x50W or 2x100W? I thought TDA7492 is a 2x50W board?


----------



## Ziggyrama

Victor_inox said:


> amp board is size of zippo lighter.power supply is about twice that. You can manufacture your own enclosure or I can make you one in chinese project boxes they sell on ebay by millions.
> Only thing to consider is that your labor is free for you, mine is not.
> 
> Email me for pictures [email protected]


I sent you an email regarding board and power supply.


----------



## Victor_inox

Ziggyrama said:


> Wow, that is small. Is that 2x50W or 2x100W? I thought TDA7492 is a 2x50W board?


TDA 7492 is 2x50, that one is 3116.


----------



## audiocholic

Gentlemen,



after reading all the positive raving about these D class amps I gathered 2 recommended pieces which were the Alpine PDX.4 and the JL HD600/4.



I just installed both yesterday and was left in shock, all things equal there not even in the same leage of a DLS A or RA series nor Helix A or even B series and to be honest dont even come close.


I stand highly against the claim that clean power is clean power and that thats all an amp will bring into a system.

the difference in width,depth,detail and warmth is just too significant to make such a statement dont care which guru comes with what type of technical explanation no way I'am gonna be convinced ..


----------



## Hillbilly SQ

Sorry they didn't work for you. Did you tweak the tune to compensate for any response variations the different amps might have? And keep in mind the amps you're comparing them to are very expensive amps. Not saying price is playing a part on how they sound but there very well could be a lot more time spent in circuit design to give the high end a/b amps that "special sauce". I will tell you this much and I stand by my statements here. I replaced a pair of Mosconi One 120.4's with a single JL XD800/8 and while the system got louder with the Mosconi a/b amps the less powerful fullrange d amp sounded like it had more control of the speakers. The sound was a lot more precise. Maybe I like the more robotic precise sound? I'll even go as far as saying I liked the XD better than the XDI I'm currently running but the XD was a refurb and had a problem that was apparently never fixed when it was replaced by the original owner. And it simply wasn't powerful enough as a whole.

So, what are the chances of me going back to a/b amps in the mobile environment? Slim to none because of size and power consumption. 4g power and main wire is more than enough for my setup and I can listen at normal to slightly elevated volume for well over an hour and the vehicle start like nothing ever happened. Still on the factory agm battery. This happens a lot at get-togethers. 3-4 lengthy demo's in I realize I haven't let the vehicle run to charge the battery in a while. Never needed a jump. Have seen a few with big power sucking a/b amps on a big upgraded battery need a jump but most of those types of people have a power supply they plug into now.

The big reason a lot of us run smaller fullrange D amps is because you can stick them just about anywhere and they'll normally be fine thermally. For example, my xdi1200.6 is in the tire well of my Grand Cherokee with full size spare still in tact. It shares space with two processors and a very inexpensive fullrange d amp that tickles the processed rearfill and IS NOT fan cooled. It's been upper 90's a lot this summer here in Arkansas and it has yet to thermal on me crammed into a dark somewhat isolated hole in a black midsize suv. It's also fan cooled.


----------



## audiocholic

Hillbilly SQ said:


> Sorry they didn't work for you. Did you tweak the tune to compensate for any response variations the different amps might have? And keep in mind the amps you're comparing them to are very expensive amps. Not saying price is playing a part on how they sound but there very well could be a lot more time spent in circuit design to give the high end a/b amps that "special sauce". I will tell you this much and I stand by my statements here. I replaced a pair of Mosconi One 120.4's with a single JL XD800/8 and while the system got louder with the Mosconi a/b amps the less powerful fullrange d amp sounded like it had more control of the speakers. The sound was a lot more precise. Maybe I like the more robotic precise sound? I'll even go as far as saying I liked the XD better than the XDI I'm currently running but the XD was a refurb and had a problem that was apparently never fixed when it was replaced by the original owner. And it simply wasn't powerful enough as a whole.
> 
> So, what are the chances of me going back to a/b amps in the mobile environment? Slim to none because of size and power consumption. 4g power and main wire is more than enough for my setup and I can listen at normal to slightly elevated volume for well over an hour and the vehicle start like nothing ever happened. Still on the factory agm battery. This happens a lot at get-togethers. 3-4 lengthy demo's in I realize I haven't let the vehicle run to charge the battery in a while. Never needed a jump. Have seen a few with big power sucking a/b amps on a big upgraded battery need a jump but most of those types of people have a power supply they plug into now.
> 
> The big reason a lot of us run smaller fullrange D amps is because you can stick them just about anywhere and they'll normally be fine thermally. For example, my xdi1200.6 is in the tire well of my Grand Cherokee with full size spare still in tact. It shares space with two processors and a very inexpensive fullrange d amp that tickles the processed rearfill and IS NOT fan cooled. It's been upper 90's a lot this summer here in Arkansas and it has yet to thermal on me crammed into a dark somewhat isolated hole in a black midsize suv. It's also fan cooled.




no reason to be sorry mate you didnt put a gun to my head insisting to buy anything  but thanks anyway much appreciated!



truth be told I really couldnt have spent more time trying to tune these amps to sound good and the installer I went to is a very well appreciated knowledged Audison dealer whom does alot of fine tuning everyday on bittens ,bit ones etc.


the result no matter what was that the DLS and Helix amps simply outperformed in dynamics and detail in the midrange and were significantly better in the highs without a slightest doubt , I mean no question at all!


I accept the fact these amps are infact expensive but arent the D classes I used also?


I mean a Helix B4 retailed for 800usd way back when it was new and thats the U.S market price (much higher) so what does a HD600/4 cost roughly the same ?


for an all out SPL guy I would definatley aggree that a D class has its advantages but for me I'am using no extra goodies and wired directly to the battery not even with a Big 3 and my supply is DLS RA20 + RA30.

with my focus being SQ and volume medium to just above medium I drive 45mins 1 way to work everyday and havent had a slighest trouble and this is on a poor ass 2016 Renault Clio nothing special


----------



## Hillbilly SQ

Whatever works just plain works. I do agree the highs could be better with fullrange D amps but they've come a long way compared to the first generation of them like 10 years ago. Guess it's a matter of what's important to you. A lot of people want big power in a small package and are willing to possibly give up some of the extra detail a larger and higher end a/b amp of similar power might give them.


----------



## DC/Hertz

Funny how some of the top cars in the US are using PDX and HDs. I don't think it's safe to blame the amps.


----------



## gijoe

audiocholic said:


> Gentlemen,
> 
> 
> 
> after reading all the positive raving about these D class amps I gathered 2 recommended pieces which were the Alpine PDX.4 and the JL HD600/4.
> 
> 
> 
> I just installed both yesterday and was left in shock, all things equal there not even in the same leage of a DLS A or RA series nor Helix A or even B series and to be honest dont even come close.
> 
> 
> I stand highly against the claim that clean power is clean power and that thats all an amp will bring into a system.
> 
> the difference in width,depth,detail and warmth is just too significant to make such a statement dont care which guru comes with what type of technical explanation no way I'am gonna be convinced ..


To be fair, the generation of PDX that you bought, is noticeably inferior to the following generation. Should have bought a PDX F4 or F6. I've also heard the HD amps are not so great fullrange (never heard them personally though). 

Class D is there, you just didn't pick the best examples unfortunately.


----------



## ChrisB

Well, when I first installed my HD900/5 many moons ago, I was surprised at how clean it sounded for a full-range Class D amplifier. Now, it did sound different from other Class AB amplifiers that were known to color the sound, especially in the mids and highs area, but, it also played much cleaner than anything I had ever experienced up until that point. 

I like my MMATS HIFI-6150D for the power aspect, but, it is borderline too powerful for my components.

It all comes down to picking your trade off. If I weren't space/current limited, I'd probably run all Arc Audio SE amplifiers or even look for all used Lunar amplifiers. Unfortunately, I am space and current limited so I stick with the full-range class d amplifiers. I'm kind of hoping that SounDigital comes out with a staggered power, multi-channel, GAN offering. I heard a rumor that they are in development, but I have no idea how long they will take to get to market.


----------



## stickpony

chuyler1 said:


> This was my take on the Alpine PDX amps when they first hit the market. I heard some systems with amps "just mounted under seats" and I thought they were going to be a joke. I was amazed at the crisp clarity, but the music lacked any sort of naturalness to it, or warmth maybe?
> 
> I know they have come a long way so I'm pretty sure my next install will be with a multi-channel class D and I'll figure out how to tune back in what I might be missing out.
> 
> Not to side track, but another thing that was popular for a while in home audio was those class T amps. How come that architecture hasn't really made it to the main stream car audio brands?


It did make it to car audio for a time. US Amps made numerous models with class T architecture, but the company that made the chips for it, Tripath technologies, went out of business. I don't know if anyone bought up their patents or not, but nothing has been done since with them.

here'ss an ebay auction with one of the class T amps:

New Old School US Amps USA-700T 2 channel amp,Amplifier,RARE,Vintage,USA,NOS,NIB | eBay


----------



## stickpony

audiocholic said:


> no reason to be sorry mate you didnt put a gun to my head insisting to buy anything  but thanks anyway much appreciated!
> 
> 
> 
> truth be told I really couldnt have spent more time trying to tune these amps to sound good and the installer I went to is a very well appreciated knowledged Audison dealer whom does alot of fine tuning everyday on bittens ,bit ones etc.
> 
> 
> the result no matter what was that the DLS and Helix amps simply outperformed in dynamics and detail in the midrange and were significantly better in the highs without a slightest doubt , I mean no question at all!
> 
> 
> I accept the fact these amps are infact expensive but arent the D classes I used also?
> 
> 
> I mean a Helix B4 retailed for 800usd way back when it was new and thats the U.S market price (much higher) so what does a HD600/4 cost roughly the same ?
> 
> 
> for an all out SPL guy I would definatley aggree that a D class has its advantages but for me I'am using no extra goodies and wired directly to the battery not even with a Big 3 and my supply is DLS RA20 + RA30.
> 
> with my focus being SQ and volume medium to just above medium I drive 45mins 1 way to work everyday and havent had a slighest trouble and this is on a poor ass 2016 Renault Clio nothing special


I guess the best thing we can take away from your experiment is that sound quality is truly subjective. Hybrid audio tends to use alot of full range class D amps in their showcars, and seem to win the highest awards with them, but then again, so much goes into their cars other than the normal DSP tweaks, so who knows? i always thought that a sound system is only as good as your weakest link in the sound chain... i guess Hybrid was able to overcome that with alot of customization......

then again, perhaps their cars only sounded very clinical, and didn't have the dynamic range and depth that you speak of...

in general i agree with you, i still think the class D has a ways to go to get that truly high end sound and depth.


----------



## drop1

You guys talking about radio interference reminded me of something.
Back when I was running up slash amps there was a signal light in my town.
Across at an angle was a Walgreens.
It was a good 75 yards away.
You could see there security monitor from the light. Those jl amps could completely scramble that monitor at 75 yds. I was young so I used to do it on purpose. Fun times.


----------



## GEM592

stickpony said:


> I don't know if anyone bought up their patents or not, but nothing has been done since with them.


According to Wikipedia, they were bought up by Cirrus Logic:

https://en.wikipedia.org/wiki/Class-T_amplifier


----------



## gijoe

stickpony said:


> I guess the best thing we can take away from your experiment is that sound quality is truly subjective. Hybrid audio tends to use alot of full range class D amps in their showcars, and seem to win the highest awards with them, but then again, so much goes into their cars other than the normal DSP tweaks, so who knows? i always thought that a sound system is only as good as your weakest link in the sound chain... i guess Hybrid was able to overcome that with alot of customization......
> 
> then again, perhaps their cars only sounded very clinical, and didn't have the dynamic range and depth that you speak of...
> 
> in general i agree with you, i still think the class D has a ways to go to get that truly high end sound and depth.


I disagree that class D has a ways to go. Measurements seem to indicate they are already there. They've got switching frequencies far higher than audible range, we're taking MHZ. I think the reason those Hybrid setups are doing so well is because the amps are NOT the week link.


----------



## Hillbilly SQ

gijoe said:


> I disagree that class D has a ways to go. Measurements seem to indicate they are already there. They've got switching frequencies far higher than audible range, we're taking MHZ. I think the reason those Hybrid setups are doing so well is because the amps are NOT the week link.


They could probably replace the amps they use with flea market amps and still do really well. It's no secret that the install and tune is nothing short of amazing in their show cars. Speaking of which, aren't the new Unity amps class d?


----------



## audiocholic

gijoe said:


> To be fair, the generation of PDX that you bought, is noticeably inferior to the following generation. Should have bought a PDX F4 or F6. I've also heard the HD amps are not so great fullrange (never heard them personally though).
> 
> Class D is there, you just didn't pick the best examples unfortunately.




Mate the PDX I had is the PDX F4 you speak of  its the version 2 that you can stack over each other.


and to be fair on this very same subject page 1 I guess many gave the JL HD series as there recommendation.



all in all I have tried Gladen D series, Helix Match D series, JL HD, Alpine PDX series my straight answer is no I'am not having this comparison done by a rookie infact the guy who tweaked / tuned the system is a highly knowledged well known expert.


and my 2nd reply isnt to you but to others stating it might be something else to blame or that things werent equal 

guys the system consists of the highest end cables,best installer workmenship, class A material for sound deadending and a very good tune I really dont understand whats to blame? 

5 gentlemen including me all didnt even need more than a few seconds to comprehand the difference I guess we all have BAT ears down here


----------



## audiocholic

Gentlemen you keep giving the example of how a firm won a contest with a D series but does that actually mean it couldnt have been better with a proper AB series?


does a 700HP Lambo require all its 700hp to beat a 250hp Camry you guys have in your market?


couldnt it be that this is a marketing thing a commercial where the firm is supporting the D series amps and winning with tremendously better equipment/workmenship than the competition?


I dont believe that the D series is anything limited to the U.S and most of the high end manufacturers in EU still make there high end stuff using AB series while they are more than able to use D series and infact do have them in there lower offering? 

there should be a good reasoning to that no?


anyhow , I heard what I needed to with my own to ears I respect whomever insists otherwise but for me its still the A-AB series for SQ in 2017 not saying that wont change in the longrun


----------



## GEM592

audiocholic said:


> Gentlemen you keep giving the example of how a firm won a contest with a D series but does that actually mean it couldnt have been better with a proper AB series?
> 
> 
> does a 700HP Lambo require all its 700hp to beat a 250hp Camry you guys have in your market?
> 
> 
> couldnt it be that this is a marketing thing a commercial where the firm is supporting the D series amps and winning with tremendously better equipment/workmenship than the competition?
> 
> 
> I dont believe that the D series is anything limited to the U.S and most of the high end manufacturers in EU still make there high end stuff using AB series while they are more than able to use D series and infact do have them in there lower offering?
> 
> there should be a good reasoning to that no?
> 
> 
> anyhow , I heard what I needed to with my own to ears I respect whomever insists otherwise but for me its still the A-AB series for SQ in 2017 not saying that wont change in the longrun


Yes X2. And please prove me wrong soon. Class D has plenty going for it, it is promising. But not quite there just yet.


----------



## audiocholic

and for those who will actually go with a D series and are stuck between choosing an Alpine and JL HD series I highly recommend the JL HD series, the PDX P4 was just power and nothing else lacked everywhere I mean subzero detail.


----------



## ChrisB

audiocholic said:


> and for those who will actually go with a D series and are stuck between choosing an Alpine and JL HD series I highly recommend the JL HD series, the PDX P4 was just power and nothing else lacked everywhere I mean subzero detail.


I could never recommend a PDX amplifier in good conscience. I went through three PDX-5s and one PDX-V9 then decided I would never purchase another PDX amplifier again. The PDX-5s were replaced under warranty and the V9 was just outside of my satisfaction or your money back guarantee period when it started acting up, so I sold it with full disclosure of the issues. Based on prior experience, I just wasn't going to go through the warranty BS again and decided it was better to take it as a lesson learned and move on to another brand!

The only thing that solved my problems in all instances was replacing the PDX amplifiers with non-Alpine amplifiers.


----------



## Hillbilly SQ

I still love being able to have my cool running class d amps tucked in my spare tire well with full size spare on 18" rim still in there. It's worth the possible hit in essque but I will admit that my hearing has been compromised over time. My buddy is running one of my old 2ch a/b amps that does 150x2 at 4 ohms. It's a US Acoustics USX2150 (non-Zed). This amp is as big or bigger than my two class D amps put together. That's an unbridged power of 300rms for the a/b vs 1000rms of class d power. Bridge and that's 460rms vs 1460rms. Did I mention that I nearly got the a/b amp hot enough to fry an egg on while I owned it and this was in a well ventilated area? 

Lots of people here in the states have switched over to quality class D amps from quality a/b amps and never looked back. A few have gone back to power sucking a/b monsters but they're few and far between. One of them the 6ch a/b McIntosh amp is nearly as wide as his car!!! And he said he doesn't bother playing the system unless the car is running or is plugged into a power supply. For the rest of us the small size and current sipping class d amps are a thing of beauty. I already mentioned I liked one of my fullrange d amps better than what most would consider a quality a/b amp. Different strokes I guessI like to put amps and processors in dead space where I won't see them for months or years at a time.


----------



## GEM592

Hillbilly SQ said:


> I still love being able to have my cool running class d amps tucked in my spare tire well with full size spare on 18" rim still in there. It's worth the possible hit in essque but I will admit that my hearing has been compromised over time. My buddy is running one of my old 2ch a/b amps that does 150x2 at 4 ohms. It's a US Acoustics USX2150 (non-Zed). This amp is as big or bigger than my two class D amps put together. That's an unbridged power of 300rms for the a/b vs 1000rms of a/b power. Bridge and that's 460rms vs 1460rms. Did I mention that I nearly got the a/b amp hot enough to fry an egg on while I owned it and this was in a well ventilated area?
> 
> Lots of people here in the states have switched over to quality class D amps from quality a/b amps and never looked back. A few have gone back to power sucking a/b monsters but they're few and far between. One of them the 6ch a/b McIntosh amp is nearly as wide as his car!!! And he said he doesn't bother playing the system unless the car is running or it's plugged into a power supply. For the rest of us the small size and current sipping class d amps are a thing of beauty. I already mentioned I liked one of my fullrange d amps better than what most would consider a quality a/b amp. Different strokes I guess


I'm running 2500 Watts rms old school (that's mostly late 80s) AB power in a compact car without sacrificing the spare tire or visibility. They require fans, big deal.

Several high end manufacturers have not given up on AB yet, and have designs that do reasonably well on footprint and heat. Class D has come a long way, but it doesn't have to be either/or and there's no need to throw the baby out with the bathwater.


----------



## sq2k1

I can agree with hillbilly's point on the size difference as I run class AB and class D in my system. The class D amp is notably smaller than the AB while producing twice the power. I have zero experience with listening to full-range class d though, but certainly would love to hear a top end system running them for comparison sake.


----------



## bnae38

Cool running, lol.

Don't get me wrong I loved my xdi1200.6 when I had it. But the output filters alone got up to 65c just sitting there. It ran plenty hot, dare I say much hotter than any of my arc ks's.

Noise floor seems higher on all class d amps that I've played with. Not tons, but it's there...

Not for me... maybe again someday. The gan technology is pretty damn interesting.

Ps, class h/g ftw.


----------



## DC/Hertz

Gary Summers seems to enjoy his PDX. I'm sure he could get whatever amps he wanted.


----------



## dgage

ChrisB said:


> I could never recommend a PDX amplifier in good conscience. I went through three PDX-5s and one PDX-V9 then decided I would never purchase another PDX amplifier again. The PDX-5s were replaced under warranty and the V9 was just outside of my satisfaction or your money back guarantee period when it started acting up, so I sold it with full disclosure of the issues. Based on prior experience, I just wasn't going to go through the warranty BS again and decided it was better to take it as a lesson learned and move on to another brand!
> 
> The only thing that solved my problems in all instances was replacing the PDX amplifiers with non-Alpine amplifiers.


I can understand your viewpoint but you mention the PDX-5s, which are the older version of the PDX amps. I read quite a few issues with the early PDX-V9 amps but I have 3 of the current PDX-V9s and they get overall very good reviews. So while I completely understand your frustration with the previous version, the new versions have had no such issues, which is why their reviews on Crutchfield are very high. So while I don't blame you with your history, I would tell others looking at class D amps, that the Alpine PDX series is quite good.


----------



## dgage

Viggen said:


> Yea I have seen that several class D home amps and some do not have auto turn on and pull less then 10w
> 
> I am leaning towards a D-sonic amp, from what I have read really good SQ and they are priced in a affordable price point. Just like in a car.... if I used A or A/B for my home setup, I would need major electrical updates.


I had a D-Sonic 3x1500w class-D amp for the home but my speakers (JTR 212) are so sensitive that the amp was complete overkill. But when I need a new amp, it will likely be a D-Sonic amp. And Dennis was great to work with.

As Victorinix mentioned, I am also fully indoctrinated as a class-D user.


----------



## Elgrosso

Funny because I'm in the opposite stage right now, have hard time to find better than the HDs.
For noise floor, power, details, dynamic, current, heat & size too of course.
I recently swapped 2/3 AB amps and so far it was not that great.
Only the zuki is really nice, but I need to re-test the HD on mids/horns soon to confirm.
Might just come from the power difference, or just from my awesome tune


----------



## DC/Hertz

I'm considering going the the RDs. But I don't know if I want to cut my power in half. I can't fit a pair of 400/4s to bridge them.


----------



## ChrisB

dgage said:


> I had a D-Sonic 3x1500w class-D amp for the home but my speakers (JTR 212) are so sensitive that the amp was complete overkill. But when I need a new amp, it will likely be a D-Sonic amp. And Dennis was great to work with.
> 
> As Victorinix mentioned, I am also fully indoctrinated as a class-D user.


I remember when I was still DJing and the QSC class D amplifiers hit the market. They were so much lighter than the Peavey and Crown amplifiers that I was using and didn't trip as many breakers. In fact, anyone who's been to a live concert within the last decade more than likely was listening to Class D amplification. Oddly, I have yet to hear one of them complain about the lack of highs or impeded dynamic range. :laugh:


----------



## audiocholic

Funny how all %90 of the manufacturers I would classify as high end that also have class D technology only offers the mentioned D class in its lower lines and %100 of the top end products are all A and AB? 


I guess these guys must learn a thing or two from this topic and get in the game ? 


Amplifiers:

Audison products

Amplifier Products BRAX, Audiotec Fischer GmbH | Innovative Car Audio


whats even worse is that Focal has a ELITE line with all stereo amps being AB, these guys are out dated arent they? 

https://www.focal.com/en/car-audio/car-audio-kits-solutions/elite/amplifiers


whats odd is the same high end manufacterer has a Performance line of amps and the only one they call SQ or dedicated to SQ is the FPX 4.400 SQ which is also explained as to differ from the remaining as being AB class? what an odd coincedence?

https://www.focal.com/en/car-audio/car-audio-kits-solutions/performance/amplifiers

https://www.focal.com/sites/www.foc...g/document/fpx4.400sq_specification-sheet.pdf

https://www.focal.com/sites/www.foc...talog/document/fpx4.400sq_technical-sheet.pdf



sorry guys but I will follow my gut or ear to be more technical and proceed with the big boys using A-AB's


----------



## dgage

There are customers paying thousands of dollars for speaker cable, $10,000 for an audio Ethernet cable, and a myriad of other snake oil audio products. Audiophiles are some of the most susceptible to voodoo products to make their system sound better. Does that make those products better? Nope, just fools being separated from their money.

Class-D is cheaper and measures about the same as a comparable non-Class-D amp. With that said, the fact that this discussion is taking place let's you know there are those that still believe class-D is flawed because, as with any new technology, it had some issues early in its development. The fact that those issues have been addressed doesn't change that there are still people who remember class-D as flawed. Or remember class-D as only being good for subwoofers. Or see the fact that it is cheaper as being synonymous with inferior. 

So as a company, if there are people that believe old technology is better, and you can charge more for it, why wouldn't you still produce those amps and market them as a premium product. There's a reason the phrase "a sucker born every minute" is so popular.

But don't believe me, get a decent class-D amp and class-A/B and see if you can measure a difference in their output using a good oscilloscope and . I bet you can't. And here is a link to a dummy load (https://www.prosoundtraining.com/2010/03/11/big-dummy-load/) that can put a load on an amplifier. A friend of mine uses something similar with AC water heater elements to test consumer and pro audio amps for home theater and studios.

And I laugh when people say they can hear a difference. If a difference can't be measured in the 20-20,000 Hz range that humans are capable of hearing, it certainly can't be heard.


----------



## audiocholic

ok now Focal,Audison,Helix,Gladen are all snake oil producers 


sorry but I'll take the snake oil if thats what youll call it so be it


----------



## Hillbilly SQ

I'll take what works best in my install even if it doesn't sound as good


----------



## audiocholic

Hillbilly SQ said:


> I'll take what works best in my install even if it doesn't sound as good




And I would respect that mate! 



stating almost all of the hi end manufacturers high end or better yet even mid line products (Voce amps vs prima) is snake oil is a response I couldnt find words for..


----------



## Hillbilly SQ

audiocholic said:


> And I would respect that mate!
> 
> 
> 
> stating almost all of the hi end manufacturers high end or better yet even mid line products (Voce amps vs prima) is snake oil is a response I couldnt find words for..


I agree. People are going to run what they want to run.


----------



## KillerBox

In my opinion, my older generation Class D - Alpine PDX-5 sounded harsh. So I was wary of buying another Class D amp but, after trying an Arc Audio xDI 1200.6, I am hooked on Class D amps now. My current system consists of three xDI 1200.6 running (150w x 14 & 600w x 2) in a Logic 7 system.

I had a few reasons for going Class D:

1.) Class D is smaller. I had limited room. If I had to use 16 channels of similar power Class a/B it would have taken up my entire truck.

2.) Class D is more energy efficient. My amps are fused at 90a each, so a total of 270a. To get similar power from Class a/B would have been approximately 450a. The largest direct drop in alternator available for my SUV is 260a.

3.) Class D doesn't create as much heat. With Class a/B, I would have had to make a choice either hearing fan noises or leaving the amps more exposed for cooling and possibly being stole.


To me it all boils down which one would sound better a lower powered Class a/B amp (say 50w per channel) driven at 100% & possibly into distortion or a Class D amp (say 150w per channel) that still has headroom.


----------



## DC/Hertz

I'll never go back to A/B. Once you figure out the car itself is the issue and how to fix that you learn the amp itself means little. You also stop swapping gear as much because you are never satisfied. 
I use to swap something every month. Now I've had the same gear for 2 going on 3 years. And I've never been happier.


----------



## DC/Hertz

Btw A/B should be much cheaper. They are 30 plus year old tech. But audiosnobs think the price equals performance. Example of selling $799655 speaker wire.


----------



## dgage

audiocholic said:


> ok now Focal,Audison,Helix,Gladen are all snake oil producers
> 
> 
> sorry but I'll take the snake oil if thats what youll call it so be it


Good point. I wasn't necessarily trying to make that comparison although I understand how that could be taken from my post. 

Which is better between the Honda Accord and the Toyota Camry for mainstream users? Neither is better, it comes down to preference.

That is how I feel about class A/B and class D. I don't see either as better though each have their pros and cons though I think class D now has a lot going for it. EDIT: Actually I do believe class-D to be better but I'm not trying to make my opinion too over the top.

But saying class-A/B is higher quality than class-D is just as bad as someone saying class-A/B is snake oil. Both comments are somewhat ludicrous.


----------



## KillerBox

After buying some music in Flac 192/24, I can say for sure my Class D amps are NOT the bottleneck to my system. 

My bottleneck is trying to find better than CD quality music!


----------



## ChrisB

DC/Hertz said:


> I'll never go back to A/B. Once you figure out the car itself is the issue and how to fix that you learn the amp itself means little. You also stop swapping gear as much because you are never satisfied.
> I use to swap something every month. Now I've had the same gear for 2 going on 3 years. And I've never been happier.


I'd only go back to class ab if I had room. Since my next vehicle may end up being a Golf R, I'll probably stick with class D. I am considering something bigger, but by 2019, I'm going to be driving a good bit if my consulting company takes off and I prefer the maneuverability of a smaller vehicle.

Furthermore, when driving on the interstate, I can't tell the difference between any class topology when played below clipping. Furthermore, I challenge any of these golden ear wonders to do the same while actually driving the car.


----------



## dgage

ChrisB said:


> Furthermore, when driving on the interstate, I can't tell the difference between any class topology when played below clipping. Furthermore, I challenge any of these golden ear wonders to do the same while actually driving the car.


I'll go one further and challenge that you won't be able to hear a difference when the car is off and your in a quiet field. I've done the testing with car, HT, and pro amps. The only one I could notice a difference with was a McIntosh tube amp, which was noticeably colored. The others showed no audible or measurable differences from 20-20,000 Hz. I did notice some roll off differences below 10 Hz (5-7 Hz) but not above there. Also didn't measure any differences before 25,000 Hz.


----------



## I800C0LLECT

Before Class A/B everybody wanted Class A. Funny how trends continue. Lucky for manufacturers, it's the cheaper topology these days.

I wonder what will come along that makes everybody sweat over class Deez


----------



## audiocholic

some comments arent that correct are they?


A/B amps producing 50rms? 
A/B's producing more distortion? 
A/B's producting heat, yeah but which amp in what conditions? I run my system with gains low and run my volume moderately high for very long (45mins one way to work) and I can barely say they are warm? 


and the most important one is probably the comments about size, yes you can get a D class the size of your hand today that can produce 8x55rms I can agree on that but if you play it smart you can find decent power for remarkably small room on A/B's too.


my system consists of the following in the following conditions and honestly I cant fault it.

HU: Cheap **** JVC KD-X340BTS 3way active (in glove department connected to Samgung tablet in dash as a screen via app remote)

Components: Pioneer C172PRS (tweeters on axis, mids on waterproof painted mdf)
RCA and speaker wire: Audison
doors: insulated with 3 different types of material in & out the door aswell as doorcard
Sub: JL 10TW3-D4 in sealed 0.5ft3
Amps: DLS RA20 & DLS RA30 (Both located under the seats)


now you guys do realize I'am getting 130rms to the mids, shouldnt that be enough?

I'am getting 70rms to the tweeters with , again should be enough no? 
I'am no bass head and do need the room in the trunk which is why I choose the JL slim TW3 and I can tell you even with %10 under at 365rms its doing pretty ok!


so I'am sorry but I have a fully active system one that runs stage 4 pioneers that I'am in love with fed by 2 amps covering all 2 mids+2tweeters + 1 sub and all that fits under my seats.


so I ask whats all the fuss about power and size?  I'll take pictures and share in a few hours gentlemen than you can tell me how crazy big my amps are


----------



## DC/Hertz

audiocholic said:


> some comments arent that correct are they?
> 
> 
> A/B amps producing 50rms?
> A/B's producing more distortion?
> A/B's producting heat, yeah but which amp in what conditions? I run my system with gains low and run my volume moderately high for very long (45mins one way to work) and I can barely say they are warm?
> 
> 
> and the most important one is probably the comments about size, yes you can get a D class the size of your hand today that can produce 8x55rms I can agree on that but if you play it smart you can find decent power for remarkably small room on A/B's too.
> 
> 
> my system consists of the following in the following conditions and honestly I cant fault it.
> 
> HU: Cheap **** JVC KD-X340BTS 3way active (in glove department connected to Samgung tablet in dash as a screen via app remote)
> 
> Components: Pioneer C172PRS (tweeters on axis, mids on waterproof painted mdf)
> RCA and speaker wire: Audison
> doors: insulated with 3 different types of material in & out the door aswell as doorcard
> Sub: JL 10TW3-D4 in sealed 0.5ft3
> Amps: DLS RA20 & DLS RA30 (Both located under the seats)
> 
> 
> now you guys do realize I'am getting 130rms to the mids, shouldnt that be enough?
> 
> I'am getting 70rms to the tweeters with , again should be enough no?
> I'am no bass head and do need the room in the trunk which is why I choose the JL slim TW3 and I can tell you even with %10 under at 365rms its doing pretty ok!
> 
> 
> so I'am sorry but I have a fully active system one that runs stage 4 pioneers that I'am in love with fed by 2 amps covering all 2 mids+2tweeters + 1 sub and all that fits under my seats.
> 
> 
> so I ask whats all the fuss about power and size?  I'll take pictures and share in a few hours gentlemen than you can tell me how crazy big my amps are


I don't see anything in your line up that let's you adjust for the car itself. If not you are not even close to potential. Deffinetly not at the point of being valid in any comparison.


----------



## audiocholic

DC/Hertz said:


> I don't see anything in your line up that let's you adjust for the car itself. If not you are not even close to potential. Deffinetly not at the point of being valid in any comparison.




Indeed your right mate,


I dont have a seperate DSP like a Helix pro or Audison bit one, but mind you the HU is 3 way capable with level adjustment per side, 13 eq band, time alignment and so on.


am I really that far from having the mentioned potential, whats the weak link? and Iam asking seriously not sarcastically to make things clear 

apart from my potential how does this effect the comparison? again not sarcastically


----------



## I800C0LLECT

Here's the difference...


----------



## audiocholic

I800C0LLECT said:


> Here's the difference...
> View attachment 187706
> View attachment 187714




guys please dont laugh at me but running the system fully active, having each channel time aligned, level matched etc and with a good 13 band eq am I really far from potential?


what is it on the dsp that I lack on my HU that makes a difference as noticeable as shown in the above 2 graphs?


----------



## I800C0LLECT

If you can correct the combined response to a point that makes you happy then you're good to go. Some people tend to be more ocd, hearing sensitive, etc. This hobby is all about picking your poison!


----------



## Ziggyrama

audiocholic said:


> guys please dont laugh at me but running the system fully active, having each channel time aligned, level matched etc and with a good 13 band eq am I really far from potential?
> 
> 
> what is it on the dsp that I lack on my HU that makes a difference as noticeable as shown in the above 2 graphs?


Do you have a 13 band EQ per channel or a single EQ for all channels?

Sent from my Pixel using Tapatalk


----------



## audiocholic

Ziggyrama said:


> Do you have a 13 band EQ per channel or a single EQ for all channels?
> 
> Sent from my Pixel using Tapatalk



single for all channels mate.


----------



## dcfis

Then, no


----------



## audiocholic

I800C0LLECT said:


> If you can correct the combined response to a point that makes you happy then you're good to go. Some people tend to be more ocd, hearing sensitive, etc. This hobby is all about picking your poison!




to be honest I used a DSP/AMP hybrid , Helix Match PP82DSP to be more precise,tuning was great but power was questionable.


looking at the JVC 3way HU I'am pretty happy to be honest, I havent recorded anything to get graphs etc but as mentioned I'am extremely happy with this setup.

the installer I work with (I'am no expert experience wise nor installation/workmenship wise which I guess is noticeable  ) is a Audison dealer and also a gentlemen whom we have good friendship with.


he did wire in and tune a bit one to see if it would make things better and indeed there was slightly better stage and edge but not enough for me to justify its price as the difference wasnt substantial.

dont know if its just the luck of the car or components but I'am certain even with the limited tuning capability I'am happy to say the least.

I mean I have zero noise floor, no hissing etc, no audible distortion even at very high volumes unless I go crazy, I have very good staging, depth ,height,width and the detail in the system is pretty good.

thanks to the amps phase control I also fine tuned the sub to mids and can say its not a bass heads ideal sub but it does get the job done for me.


----------



## audiocholic

dcfis said:


> Then, no



Gentlement dont call me stupid, I have a new born whom has growing pains (teeth I guess, every month theres something esle  ) and havent had sleep for a while.


but I honestly didnt get the reply mate.


----------



## Hillbilly SQ

That 13 band mono eq wouldn't begin to touch the amount of eq you need to properly correct for the car environment. I've heard really good sounding systems with really basic eq but imaging was marginal at best. In car audio you're tuning for the "room" more than anything. On the flip side a dsp can make a system sound WORSE really easily in the wrong hands. 

And my two class d amps are likely way smaller than your two amps and just barely fit where I put them. I like stuff completely out of the way where it doesn't effect the function of the vehicle. I'm saying this but have a 2.6 cube ported box with a 12" in it but it's a necessary evil for the uber essque sub bass.


----------



## audiocholic

Hillbilly SQ said:


> That 13 band mono eq wouldn't begin to touch the amount of eq you need to properly correct for the car environment. I've heard really good sounding systems with really basic eq but imaging was marginal at best. In car audio you're tuning for the "room" more than anything. On the flip side a dsp can make a system sound WORSE really easily in the wrong hands.
> 
> And my two class d amps are likely way smaller than your two amps and just barely fit where I put them. I like stuff completely out of the way where it doesn't effect the function of the vehicle. I'm saying this but have a 2.6 cube ported box with a 12" in it but it's a necessary evil for the uber essque sub bass.



perhaps I should change the friend and try another installer/tuner in a different city.


which would you advise a Helix dsp or bit one, only ones available in this market are these 2 little boys and the helix is roughly %50 more expensive.


----------



## Hillbilly SQ

Helix every time. But you MUST know what you're doing when tuning it. Plenty of tutorials on here.


----------



## Ziggyrama

audiocholic said:


> Gentlement dont call me stupid, I have a new born whom has growing pains (teeth I guess, every month theres something esle  ) and havent had sleep for a while.
> 
> 
> but I honestly didnt get the reply mate.


Don't worry about it, no one is calling you stupid. No one is born with this knowledge. I think dcfis is saying that you are not near your full potential because you're lacking one of the most important tuning features: per channel EQ. The problem is, in a car, the frequency response is vastly different between left and right side. Unless you drive an F1 car, you don't sit in the center of the car. To illustrate, below is the original measurement of my left and right channels for the tweeters and mids. Ignore the tweeters for now, look at the plots for mids. Notice how different they are at my listening position. You cannot fix this with a single EQ. You cannot fix this by playing around with gains or messing with phase. Some frequency ranges had 10dB difference between L and R!!! Frankly, it sounded like poop. Most of the problems have been fixed by applying EQ to each channel individually and correcting the issues.

We obviously don't know what your system sounds like. You seem to be happy with it. That being said, it is highly likely that whatever you have now, it would be significantly better if you had per channel tuning capability.

Original measurement:










This is what it looks like when I applied DSP and corrected for frequency response issues:










I hope you can see how much of a difference you get. And most importantly, my ears are definitely hearing it.


----------



## Hillbilly SQ

I need to find a new image hosting site but y'all shoulda seen my door mounted 6.5's without l/r eq. I measure and tune at 1/12. I feel that's a good compromise between overly smoothed and splitting hairs. I will split hairs if there are unused eq bands available. I fixed A LOT with just 6 bands of peq for each driver. Sail mounted tweeters weren't too terrible bad. This is with a cross point of around 2500hz LR4. (24db linkwitz riley slope)...now you will have dips in the eq that no amount of eq will fix. You just have to hope they're narrow enough that your brain skips over those dips and fills in the missing material.


----------



## audiocholic

Gentlemen I have a few words to say:


1) I appologize for making hard statements without the background required behind,thought I did due to belief in my installer.

2) I greatly appreciate the kind,quality responses full of patience , my thanks goes especially to Hillbilly SQ, Ziggyrama but also to other forum mates.



seeing that a D class is sufficient and that I truely require a DSP would you guys say a Helix P six would be sufficient and worthwhile investment are there any downsides to this product?


I see it has 2x 230rms @ 2ohms would this be enough for a dual VC 2ohm run straight to the coils via 2 outputs?


my only concern is I have owned a Audison 8.9bit and a Helix Match PP82DSP and these AMP/DSP hybrids really didnt match there claimed RMS output (The 8.9 was far from 35rms and the PP82DSP wasnt even close to the equally quoted 55rms audison SR5)


----------



## GEM592

I agree if you've married yourself to class D, you're going to need EQ, and alot of it, left, right, up, down, in, out, and all around. If you haven't convinced yourself by then, just remember you're wrong. It is the second coming. A billion Watts under your seat for less than a trip to the grocery store. What could possibly go wrong?


----------



## dcfis

GEM592 said:


> I agree if you've married yourself to class D, you're going to need EQ, and alot of it, left, right, up, down, in, out, and all around. If you haven't convinced yourself by then, just remember you're wrong. It is the second coming. A billion Watts under your seat for less than a trip to the grocery store. What could possibly go wrong?


----------



## benny z

GEM592 said:


> I agree if you've married yourself to class D, you're going to need EQ, and alot of it, left, right, up, down, in, out, and all around. If you haven't convinced yourself by then, just remember you're wrong. It is the second coming. A billion Watts under your seat for less than a trip to the grocery store. What could possibly go wrong?




If you haven't figured out you're going to need EQ, a lot of it, left, right, up, down, sideways, diagonal, consign opposed - yada - in a car - regardless of amplifier topology... well... good luck!


----------



## Hillbilly SQ

GEM592 said:


> I agree if you've married yourself to class D, you're going to need EQ, and alot of it, left, right, up, down, in, out, and all around. If you haven't convinced yourself by then, just remember you're wrong. It is the second coming. A billion Watts under your seat for less than a trip to the grocery store. What could possibly go wrong?


So a/b amps magically fix the train wreck a vehicle cabin causes? You're saying you don't need nearly as much l/r eq with a/b amps? Geez, it was less than two years ago I had 8 channels of a/b power from a forum boner under the front seats of my Ram. I don't recall the unprocessed spaghetti mess of a frequency response being any worse when switching to class d.


----------



## dsw1204

I am in the process of purchasing a 5-channel amp. I am wanting a Zapco Z-150.6 LX (still in the process of saving the money for it...it's not a cheap amp, at least for my budget). I want this amp because I've drunk their Koolaid and want all their high-end componontry they have put in those amps.

I would consider a Class D amp if there was one that had the same, or similar, high-end componentry, but I don't know of any. What are the 5-channel Class D amps that are built with the componentry similar to Zapco's Z-LX line? I'd be very interested to know these amps.


----------



## dcfis

You man how the z-lx used to be built? You can find plenty with the medium grade stuff they use now.


----------



## ChrisB

Hillbilly SQ said:


> So a/b amps magically fix the train wreck a vehicle cabin causes? You're saying you don't need nearly as much l/r eq with a/b amps? Geez, it was less than two years ago I had 8 channels of a/b power from a forum boner under the front seats of my Ram. I don't recall the unprocessed spaghetti mess of a frequency response being any worse when switching to class d.


That individual sounds like a disciple of a certain old school car audio guy that is revered by the people who buy his stuff. You know, the same guys who bragged about taking first place in all their SQ classes when there were no other competitors? Going further, if there was a competitor, they would switch to another class with no competitors to get their first place participation trophy by default and brag about it online.


----------



## audiocholic

hey guys now that I have decided to go the dsp/amp path again which of the following would you guys recommend considering there prices:


both used:


Helix P six 6 x 120rms : 850euros

Mosconi 80.6 DSP 6x80rms: 600 euros.


please note the mids are Pioneer stage 4 C172prs 50rms but they do take alot more rms with ease.


please also note both amps allow for 3 way mids plus an extra 2 line outputs with dsp control to power a seperate mono if needed.


----------



## dcfis

You don't want to start with one of the c-dsp and the mic for half price New or the same with a mic? Otherwise those are fat dsps. 

Oh and I hear ya man, the reason I write when I do is after I feed the 5 week old.


----------



## audiocholic

dcfis said:


> You don't want to start with one of the c-dsp and the mic for half price New or the same with a mic? Otherwise those are fat dsps.
> 
> Oh and I hear ya man, the reason I write when I do is after I feed the 5 week old.



congradulations on the new born may he/she be blessed with health,love and laughter! hope she/he is healthy aswell as the mother mate. 


as for the C-DSP its brand new price here is roughly 450 euros without the mic, I thought of it and said to my self the P six saves me a 4 channel amp aswell as mono and for 400 euros difference that seems like an ok deal.


but again you guys are the experts so please let me know ,thanks in advance


----------



## dcfis

Yeah, if the 6x8 mini dsp is that close to a used helix you are on the right track. Thanks for the kind words and hope you and yours are happy and healthy too!

Ps. Those stage 4s are amazing speakers that should be produced still today


----------



## audiocholic

dcfis said:


> Yeah, if the 6x8 mini dsp is that close to a used helix you are on the right track. Thanks for the kind words and hope you and yours are happy and healthy too!
> 
> Ps. Those stage 4s are amazing speakers that should be produced still today




thank you sir!,


ours had severe cholic that later turned into a cracked anal lining, with no cure but just a cream to ease the pain and hot water to speed the natural curing that took 4 months it wasnt easy to say the least 


whats most important is take all easy and whatever happens keep calm its very easy to get frustrated, angry and have a long relationship torn with just a few word spoken out of our asses due to sleepless nights.



going back to the subject just send an email to the Helix P six owner lets see what happens.

as for the Pioneer Stage 4's they are the best thing that happened to me after my baby , had Helix E62C which is also praised for, for me its no comparison that the C172prs is in a whole different level/league


----------



## Hillbilly SQ

You still need a measurement mic and rta software to get everything lined up. Yes people with highly trained ears can pull it off without a mic but most can't. The first time I used a mic and rew I accomplished more in just a few hours than I could from years of trying to do it by ear. Then again, I'm in the majority of people in this hobby who don't have highly trained ears.


----------



## audiocholic

Hillbilly SQ said:


> You still need a measurement mic and rta software to get everything lined up. Yes people with highly trained ears can pull it off without a mic but most can't. The first time I used a mic and rew I accomplished more in just a few hours than I could from years of trying to do it by ear. Then again, I'm in the majority of people in this hobby who don't have highly trained ears.



thanks , would auto tune available on the Helix RTA work well when aligned with a Umik-1 or are all these auto tunes just worthless?


shall I purchase this amp I indeed will get the rew software along with a umik-1 to get me started on this learning path.


----------



## Hillbilly SQ

Not familiar with auto tune. As long as you're getting the right tools to help you reach potential that's all that matters. Never stop learning. You have a little future audiophile to introduce to the hobby at some point


----------



## audiocholic

Hillbilly SQ said:


> Not familiar with auto tune. As long as you're getting the right tools to help you reach potential that's all that matters. Never stop learning. You have a little future audiophile to introduce to the hobby at some point




25 years from now in 1992 if someone told you you would be speaking face to face on a cellular phone, 

that tv's would be half an inch thick, 
that diesel cars would win in drag races, 
that porn would be a touch of a button away 
that a 120rms x 6 amp including dsp would be soo small.

we would tell them off

who nows what is waiting for my little Audiophile girl,joking aside you have to see her responses to music,especially Latin for some reason


----------



## Hillbilly SQ

Latin music gets you moving. I've always liked it


----------



## Ziggyrama

audiocholic said:


> 25 years from now in 1992 if someone told you you would be speaking face to face on a cellular phone,
> 
> that tv's would be half an inch thick,
> that diesel cars would win in drag races,
> that porn would be a touch of a button away
> that a 120rms x 6 amp including dsp would be soo small.
> 
> we would tell them off
> 
> who nows what is waiting for my little Audiophile girl,joking aside you have to see her responses to music,especially Latin for some reason


I found new kids movies incorporate a lot of music that is specifically designed to get them hooked, in a good way. My 4 year old daughter is bonkers over Trolls movie and the soundtrack. There is definitely a profile that they are using, and they know what kids like to hear. That and 'I want to be sadated' by Ramones, lol. Go figure.

Sent from my Pixel using Tapatalk


----------



## swoardrider

thereddestdog said:


> One of the first things I noticed while getting gear together after an audio hiatus was that there are a lot of amps out there now that are full range and Class D, which were only recommended for subwoofers in my time.
> 
> Now, I'm firmly in the A/B camp, and I'm sure there are a few A fanatics out there still, but how do these new school Class-D amps fair?


This is been my experience on and off for the past 25 years in this hobby:

Present time =FULL RANGE SOUND QUALITY > *(Tube)...(Class A)....(Class A/B).(Class G/H)....(Class D)* < SIZE/EFFICIENCY/PRICE PER WATT

15 plus years ago = FULL RANGE SOUND QUALITY > *(Tube)...(Class A)....(Class A/B)................(Class D)* < SIZE/EFFICIENCY/PRICE PER WATT

It seems that in the SQ world, you can take a great install, with great speakers, a powerful DSP, and a clean class D amplifier and get award winning results. But there is also more than one way to get great sound. Not all of us have the ability to mount 3" speakers on A-pillers, or the ear and knowledge to tune, or put 500lbs of sound deadener in a daily driver, etc. For some people, a good class A/B amp that "warms up" the sound stage on a $1500 active 2-way may be the key to getting to desired results. There is a spot in car audio for all types of amplifiers, IMO. 

I just currently finished a build where I replaced a full range class D (Alpine PVX) with a class A/B (Mosconi AS) and I'm much happier, but wondering if I should have gone class G/H (Arc KS) because of more power, less price, and same size. Im starting another build in which the full range will most likely be class G/H, as I've had great experience in a boat with class G/H.

Good simple read I found while researching class G/H:

_Class G – the ultimate amplifier technology - explained.......... In simple terms!
First, some history: conventional Class A and Class AB design have good points and bad points Class A – an inefficient solution to the class A/B crossover problem
Pros – does not suffer from crossover distortion and is often observed to be totally transparent for this reason offering a level of realism through low level accuracy that is seldom achieved in a class A/B design.
Cons – When used in a solely Class A design, it is wildly inefficient as it will always be drawing full power even with no signal to amplify, for this reason Class A ampli ers usually offer lower power outputs and is often found only in esoteric high-end designs.
Class AB – the most common amplifier design Pros - Far more efficient than pure Class A
Cons - suffers from crossover distortion at low levels – remember the magic of audio reproduction is not the loud stuff but rather it is the tiniest of details that create that sense of reality that we search for.
Class G – complex to design, but engineered correctly, the clever solution. Pros – Greater efficiency and transparency, with less wasted heat energy.
Cons – Expensive to engineer and hard to perfect, hence seldom seen.
What exactly is Class G? Like a hybrid car engine, Class G implements multiple power supplies rather than just a single supply. If a dynamic signal is received that goes beyond the capability of this first power supply, the secondary supply is gradually brought in up to full rated power output as required. is gives a very efficient design as additional power is only used when required, much like a turbo-charger. Modern high speed silicon allows us the make this switch faster that would ever be required, even way beyond the audio bandwidth, so there is no “turbo lag”.
The first power supply is of lower power and within this region we run in pure Class A, which has no crossover distortion. As the secondary supply is only used when required, extreme levels of power are possible because very little energy is wasted in the amplifier as heat when it is not being used. Without control this power would be ill-used, so like high performance car tyres, multiple output devices within the amplifier keep a tight grip on the loudspeaker at all times, ensuring your listening experience never “leaves the road”.
Class G Summary By Arcam_


----------



## swoardrider

thereddestdog said:


> One of the first things I noticed while getting gear together after an audio hiatus was that there are a lot of amps out there now that are full range and Class D, which were only recommended for subwoofers in my time.
> 
> Now, I'm firmly in the A/B camp, and I'm sure there are a few A fanatics out there still, but how do these new school Class-D amps fair?


This is been my experience on and off for the past 25 years in this hobby:

Present time = FULL RANGE SOUND QUALITY > *(Tube)...(Class A)....(Class A/B).(Class G/H)....(Class D)* < SIZE/EFFICIENCY/PRICE PER WATT

15 plus years ago = FULL RANGE SOUND QUALITY > *(Tube)...(Class A)....(Class A/B)................(Class D)* < SIZE/EFFICIENCY/PRICE PER WATT

It seems that in the SQ world, you can take a great install, with great speakers, a powerful DSP, and a clean class D amplifier and get award winning results. But there is also more than one way to get great sound. Not all of us have the ability to mount 3" speakers on A-pillers, or the ear and knowledge to tune, or put 500lbs of sound deadener in a daily driver, etc. For some people, a good class A/B amp that "warms up" the sound stage on a $1500 active 2-way may be the key to getting to desired results. I recently heard an 11 year old system with custom tube and class A amps, which sounded soooo clean. But I still like the sound of my new (and waaaay less$$$) A/B set up better, even with speaker that have yet to be fully broken in. There is a spot in car audio for all types of amplifiers, IMO.

I just currently finished a build where I replaced a full range class D (Alpine PVX) with a class A/B (Mosconi AS) and I'm much happier, but wondering if I should have gone class G/H (Arc KS) because of more power, less price, and same size. Im starting another build in which the full range will most likely be class G/H, as I've had great experience in a boat with class G/H.

Good simple read I found while researching class G/H:

_Class G – the ultimate amplifier technology - explained.......... In simple terms!
First, some history: conventional Class A and Class AB design have good points and bad points Class A – an inefficient solution to the class A/B crossover problem
Pros – does not suffer from crossover distortion and is often observed to be totally transparent for this reason offering a level of realism through low level accuracy that is seldom achieved in a class A/B design.
Cons – When used in a solely Class A design, it is wildly inefficient as it will always be drawing full power even with no signal to amplify, for this reason Class A ampli ers usually offer lower power outputs and is often found only in esoteric high-end designs.
Class AB – the most common amplifier design Pros - Far more efficient than pure Class A
Cons - suffers from crossover distortion at low levels – remember the magic of audio reproduction is not the loud stuff but rather it is the tiniest of details that create that sense of reality that we search for.
Class G – complex to design, but engineered correctly, the clever solution. Pros – Greater efficiency and transparency, with less wasted heat energy.
Cons – Expensive to engineer and hard to perfect, hence seldom seen.
What exactly is Class G? Like a hybrid car engine, Class G implements multiple power supplies rather than just a single supply. If a dynamic signal is received that goes beyond the capability of this first power supply, the secondary supply is gradually brought in up to full rated power output as required. is gives a very efficient design as additional power is only used when required, much like a turbo-charger. Modern high speed silicon allows us the make this switch faster that would ever be required, even way beyond the audio bandwidth, so there is no “turbo lag”.
The first power supply is of lower power and within this region we run in pure Class A, which has no crossover distortion. As the secondary supply is only used when required, extreme levels of power are possible because very little energy is wasted in the amplifier as heat when it is not being used. Without control this power would be ill-used, so like high performance car tyres, multiple output devices within the amplifier keep a tight grip on the loudspeaker at all times, ensuring your listening experience never “leaves the road”.
Class G Summary By Arcam_


----------



## dcfis

Anybody got a list of proven G/H amps?


----------



## sqnut

dcfis said:


> Anybody got a list of proven G/H amps?


Genesis.


----------



## sqnut

swoardrider said:


> This is been my experience on and off for the past 25 years in this hobby:
> 
> Present time = FULL RANGE SOUND QUALITY > *(Tube)...(Class A)....(Class A/B).(Class G/H)....(Class D)* < SIZE/EFFICIENCY/PRICE PER WATT
> 
> 15 plus years ago = FULL RANGE SOUND QUALITY > *(Tube)...(Class A)....(Class A/B)................(Class D)* < SIZE/EFFICIENCY/PRICE PER WATT
> 
> It seems that in the SQ world, you can take a great install, with great speakers, a powerful DSP, and a clean class D amplifier and get award winning results. But there is also more than one way to get great sound. Not all of us have the ability to mount 3" speakers on A-pillers, or the ear and knowledge to tune, or put 500lbs of sound deadener in a daily driver, etc. For some people, a good class A/B amp that "warms up" the sound stage on a $1500 active 2-way may be the key to getting to desired results. I recently heard an 11 year old system with custom tube and class A amps, which sounded soooo clean. But I still like the sound of my new (and waaaay less$$$) A/B set up better, even with speaker that have yet to be fully broken in. There is a spot in car audio for all types of amplifiers, IMO.
> 
> I just currently finished a build where I replaced a full range class D (Alpine PVX) with a class A/B (Mosconi AS) and I'm much happier, but wondering if I should have gone class G/H (Arc KS) because of more power, less price, and same size. Im starting another build in which the full range will most likely be class G/H, as I've had great experience in a boat with class G/H.


I'd say that is long on opinions, but short on facts.


----------



## Holmz

sqnut said:


> I'd say that is long on opinions, but short on facts.


I'd say you're right.

Tube are woeful on fidelity and harmonic distortion.
I know as I have a set.

The class G are elegant from a power perspective, but after that it is hard to beat a class AB.
Whether class D gets to class AB levels is really only a concern with twitters, and as one can run smaller amps for them, it is somewhat a exercise in debate.


----------



## swoardrider

sqnut said:


> I'd say that is long on opinions, but short on facts.


Correct. The first 2/3rds of my post is my opinion based on my experience, and the last 1/3 is a fact, written by Arcam Audio UK


----------



## swoardrider

Holmz said:


> I'd say you're right.
> 
> Tube are woeful on fidelity and harmonic distortion.
> I know as I have a set.


The natural distortion of the tube is what gives it it's sound quality. Obviously theres a reason you have a set, and it's certainly not because they are the norm.

EX: If your listening to a Muddy Waters track, where he's using a tube amp (and quite possibly a tube mic) you may prefer to listen to the recording on a tube amp.

And, you may find the opposite listening to say EDM, where a tube "colors" the track too much.

For this reason, I feel it is why the masses prefer Class A in home audio SQ, and Class A/B in car audio SQ. All around, they typically make all types of recordings sound pretty darn good.


----------



## dcfis

What kinda chinesium alexipress tube amps are toy guys basing these proclamations on?


----------



## Hillbilly SQ

So, if an artist used some kind of special tube amp to "color" the sound wouldn't you really want an amp that would reproduce the recording as correctly as possible without "coloring" the sound?


----------



## DC/Hertz

So much crazy in here.


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## dcfis

That's exactly what some prefer


----------



## Holmz

swoardrider said:


> The natural distortion of the tube is what gives it it's sound quality. Obviously theres a reason you have a set, and it's certainly not because they are the norm.


Natural distortion is what I am talking about.
It does not have fidelity with the input, it colours it.




swoardrider said:


> EX: If your listening to a Muddy Waters track, where he's using a tube amp (and quite possibly a tube mic) you may prefer to listen to the recording on a tube amp.
> 
> And, you may find the opposite listening to say EDM, where a tube "colors" the track too much.


I have no control over the recording. I would like to hear it how it is ment to be. Not coloured with lipstick, blush, and highlights and perfume in some "natural" warmth.




swoardrider said:


> For this reason, *I feel* it is why the masses prefer Class A in home audio SQ, and Class A/B in car audio SQ. All around, they typically make all types of recordings sound pretty darn good.


I see your feeling, but where is your evidence for that statement?

Does making recording sound good equate with either fidelity or with quality?




dcfis said:


> What kinda chinesium alexipress tube amps are toy guys basing these proclamations on?


Good point. I am using VTLs MB100, and an Audible Illusions tube pre.

It is my opinion, that tube amps tend to work better with higher impedance speakers, and that transistor with lower.
Also there is more than one design of tube circuit, however they are all getting lumped together in "rainbows and unicorns" land.




Hillbilly SQ said:


> So, if an artist used some kind of special tube amp to "color" the sound wouldn't you really want an amp that would reproduce the recording as correctly as possible without "coloring" the sound?


That is what I agree with.


----------



## dcfis

DC/Hertz said:


> So much crazy in here.


Seriously, I know you have had a spl machine. Have you ever REALLY heard a High end stereo? There are meets in your area im sure. Do it and your audio world wont be so black and white. There is no my way or the highway, there are exceptions to every rule and conditions. Along the way you will find There are systems you could love for the rest of your life and go against everything you thought you knew and what you liked. One thing you wont find is a seasoned audiophile with a black and white view and such rigid dogmas.


----------



## DC/Hertz

dcfis said:


> Seriously, I know you have had a spl machine. Have you ever REALLY heard a High end stereo? There are meets in your area im sure. Do it and your audio world wont be so black and white. There is no my way or the highway, there are exceptions to every rule and conditions. Along the way you will find There are systems you could love for the rest of your life and go against everything you thought you knew and what you liked. One thing you wont find is a seasoned audiophile with a black and white view and such rigid dogmas.


Lol. 
Carry on.


----------



## DC/Hertz

Sure I'll waste some of my time. 
Do you know what sound quality is? Well it's not a specific amp topology that shouldn't be coloring anything. 
It's getting rid of all the rattles in the interior
It's getting the sub and mid bass in phase and blended 
It's getting delay right so you get a stage
It's getting a good response curve from all the crazy stuff the interior is doing to it. 
It's getting a stable curve so the imaging doesn't smear and you get some layering. 

Nothing that matters cares what type of amp is used. 
That is black and white.


----------



## DPGstereo

.


What is the goal of a *SQ tune*?

To reproduce, as close to as possible, the sound of the original recording?
Given that the studio engineer decides what that sound is.

Or does the *SQ tune* have other objectives?

I ask because I recently sat in a 3 time world class winning vehicle. I hold my impression until I understand what the objective of a _*SQ tune*_ is.



.


----------



## DPGstereo

.

View attachment 190034

.
View attachment 190042

.
View attachment 190050



Some will recognize this vehicle.





.


----------



## deefIV

My brother-law is a professional (well paid) song writer and lead singer. We've had this conversation a few times. Artists care more about live sound and experience than recorded. We can compare high end home audio and car audio systems all we want. One never sounds the same as the other. 

His band is touring with One Republic right now and they played in Phoenix Tuesday night. I spent several hours tuning the last few nights trying to reproduce that experience in my truck to no avail. Though I think it sounds pretty damn good. 

I lean toward "SQ". I've demoed some amazing and very expensive systems (home and car). In my opinion nothing is better than live and I know it's not possible to recreate that perfectly in a car. 

Point is...I find in humorous that so many of us argue about the definition of SQ and what music should sound like. Or what the music producer and artist wants it sound like. It's so subjective. 

To the thread topic...I just went from Helix PSix mk 2 to Gladen 250c4/Helix DSP Pro mk 2 and then back because I like the class D sound better. But that's just me. 




Sent from my iPhone using Tapatalk Pro


----------



## swoardrider

in my opinion, this








sounds better than this








But to each his own.


----------



## DPGstereo

.


Completely understand where you're coming from. I'm a drummer, play with a band twice a week. Know the sound before and after going thru a PA. 

As a point of reference, I use my 2-chanel stereo in my bedroom (_B&W 802D_, _JL Audio Fantom 13_" powered sub, _McIntosh MC1201_(1,200 watts) mono amp on each speaker, _McIntosh C2200_ tubed pre-amp). The mixing world knows that the infamous Abbey Roads studio in London uses _B&W 800_ series as reference monitors in their final mixing studio.

Or listen through my home theater system, in 2-chanel, through _Genelic 1038B_ (powered 3-way studio monitors, tweet, 5" mid, 15" woofer), two _Genelic 7071A_ subs (dual 12" powered sub woofer system), _Lexicon MC12B_ pre-amp. _Genelic_ is a favorite reference active monitoring system used in many professional studios. It's been said many times, in the pro-audio world, that artist always love to hear their mix through large _Genelic_ monitors. 

Point being, I am use to listening to music through a "reference system". I recently attended a sanctioned SQ competition, best of the best, and listen to systems that seemingly have no budget. One vehicle, I was told was a 3-time world champion, from Las Vegas area. Over $50k in install and gear. Dash of vehicle was completely removed, custom re-fabracated to optimize speaker location. A work of art. Custom leather.... 
Owner was kind enough to allow me to sit in driver seat and demo'd system for me. Thank you...
However when I listened to the system, I was shocked by what I heard.
Had 4 Illusion C12XL subs in custom enclosure. All powered by Mosconi. Illusion C10 custom installed in front passenger foot well area for up-front bass. 
Image was amazing, system was very quite, as one would expect.
But the tune, SQ...??? Very flat, not airy at all in the top end. The bass was very subdued. Not at all like the original recording would sound on a reference system?
So, again, I wonder what is the objective of the SQ tune....?
Clearly the system is more than capable of sounding amazing.
What I hear is, over exaggerated mid-bass, high frequencies rolled off and all but around, 30Hzs and lower, of the bass is rolled off.
This was a common theme with every vehicle I listened to. Strong mid-bass and mid-range, very attenuated higher frequencies and rolled off bass, except for the very low frequencies which seemed to be boosted.

*What's the deal?*

Hearing different comments and after discussions with judges, seems they look down on "the typical boosted 40Hzs" and "smiley curve eq" tune that rookies typically do. And I agree, to a point. 



.


----------



## DPGstereo

.

For my quiet, daily driver, I went higher end A/B...McIntosh/Mosconi amps.


For my Jeep TJ I went class D...JL Audio HD600/4 & HD1200/1 amps.


Not a fair comparison given the substantial price difference. Class D has it's place.




.


----------



## sqnut

DPGstereo said:


> *What's the deal?*
> 
> Hearing different comments and after discussions with judges, seems they look down on "the typical boosted 40Hzs" and "smiley curve eq" tune that rookies typically do. And I agree, to a point.
> 
> 
> 
> .


Did you establish your credentials with the person giving you the demo, like you did in the posts above? If so, there's a high chance that you got what is known as, a s*** tune in the lanes. 

Also, if you really want accurate and balanced to the recorded sound in a car, like the 'Genelec' in your rig, then the judges are right, not boosting 40hz and not using a smiley eq curve are things you have to agree with 100%, and not to a point.


----------



## sqnut

DPGstereo said:


> .
> 
> For my quiet, daily driver, I went higher end A/B...McIntosh/Mosconi amps.
> 
> 
> For my Jeep TJ I went class D...JL Audio HD600/4 & HD1200/1 amps.
> 
> 
> Not a fair comparison given the substantial price difference. Class D has it's place.
> 
> 
> 
> 
> .


You do know that the Genelec's that you so love, are powered by D class amps too. Scroll down towards the bottom.

https://www.genelec.com/technical-glossary


----------



## Weightless

Lol

Sent from my SM-N920P using Tapatalk


----------



## Hillbilly SQ

When I dial in my tonality curve I have the whole bandwidth fairly flat by ear. I don't give a damn what the rta says when it comes to a tonality curve unless I'm hunting for an obnoxious hot spot that needs cut. What I end up with for final curve is what I end up with. I will add heat here and there to enhance the experience. Sub is flat BY EAR from 25-80 as it hands off to the midbass. I need to take a screenshot of my curve and post it. Would probably give the pro's a good laugh. Or make them puke. 

As for the "**** tune", I've heard of people doing it but doubt anyone would openly admit to it. It boggles my mind why someone would sandbag their system unless they're insecure about something. I'm pretty sure most competitors have the black tie tune the judges hear, a tune for driving, and a tune for cutting loose with. The black tie tune is cool to hear just how accurate a car can sound but I want to hear a tune that reflects the owner's personality. For the record I've never competed and quite honestly probably never will. If I did compete it would be for spl.


----------



## DPGstereo

sqnut said:


> Did you establish your credentials with the person giving you the demo, like you did in the posts above? If so, there's a high chance that you got what is known as, a s*** tune in the lanes.
> 
> Also, if you really want accurate and balanced to the recorded sound in a car, like the 'Genelec' in your rig, then the judges are right, not boosting 40hz and not using a smiley eq curve are things you have to agree with 100%, and not to a point.



Agree with all of that. Seems the SQ tunes I've been demo'd, suck the life out of the music. I realize personal preference....I'm just not sure the goal of the SQ tune? From what I've heard, so far, the average listener would not like the sound of a SQ tune, to listen to music. I suspect the conversion may go similar to "you think that sounds good?" or "you paid how much for that"


.


----------



## I800C0LLECT

DPGstereo said:


> Agree with all of that. Seems the SQ tunes I've been demo'd, suck the life out of the music. I realize personal preference....I'm just not sure the goal of the SQ tune? From what I've heard, so far, the average listener would not like the sound of a SQ tune, to listen to music. I suspect the conversion may go similar to "you think that sounds good?" or "you paid how much for that"
> 
> 
> .


This is why we tune....


----------



## DPGstereo

sqnut said:


> You do know that the Genelec's that you so love, are powered by D class amps too. Scroll down towards the bottom.
> 
> https://www.genelec.com/technical-glossary




Not bashing on class D amps. Again, they have their place. Powered monitors and powered subwoofers are a perfect example. Car audio, in my opinion, is another good use. However, I haven't heard any class D that can match the sonic limits of a good class A or A/B. Same with tube amps. They do sound great, and what they do add, especially at high volume is a little bit of distortion. Many people like that, just don't realize it. Take a good tube amp, turn it up to the point of just starting to breaking-up/distorting, most will stop there with the volume control and say that sounds good. The point of slight distortion = level of being loud. Play a clean solid state system, that has a lot of headroom...it's much louder than perceived because of no distortion. In a good system, slight distortion = sense of loud. My experience is a good class D amp performs similar to a tube amp. And, nothing wrong with that. 
All things being equal, tune, deadening, alignment... my experience is a class A or A/B is sonically more reviling than class D amp. Price may become an issue...but if price and size are not the deciding factor...class A or A/B wins.
...yea but, so and so wins with class D...because the know how to set-up and tune. Let that guy build two exact vehicles...one class D and other vehicle use say Brax MX4's...which one do you think would win?




.


----------



## DC/Hertz

DPGstereo said:


> Not bashing on class D amps. Again, they have their place. Powered monitors and powered subwoofers are a perfect example. Car audio, in my opinion, is another good use. However, I haven't heard any class D that can match the sonic limits of a good class A or A/B. Same with tube amps. They do sound great, and what they do add, especially at high volume is a little bit of distortion. Many people like that, just don't realize it. Take a good tube amp, turn it up to the point of just starting to breaking-up/distorting, most will stop there with the volume control and say that sounds good. The point of slight distortion = level of being loud. Play a clean solid state system, that has a lot of headroom...it's much louder than perceived because of no distortion. In a good system, slight distortion = sense of loud. My experience is a good class D amp performs similar to a tube amp. And, nothing wrong with that.
> All things being equal, tune, deadening, alignment... my experience is a class A or A/B is sonically more reviling than class D amp. Price may become an issue...but if price and size are not the deciding factor...class A or A/B wins.
> ...yea but, so and so wins with class D...because the know how to set-up and tune. Let that guy build two exact vehicles...one class D and other vehicle use say Brax MX4's...which one do you think would win?
> 
> 
> 
> 
> .


Well the guy that wins everything with class D had MCs before. So that crushes your opinion.


----------



## drop1

Im about to run a test soon as my mosconis come in.
Im currently running a jl bridged to 300w per on my highs using passives. Im using only the auto eq feature of rew on a house curve intentionally until my amps arive. Im going active but before i do im going to run an mosconi as100.4 bridged to 310 watts per into the same passives amd componets using the same tune. Then ill use the same house curve and the rew auto eq import feature which should give me as close to the same tune as possible. 
Very curious.


----------



## sqnut

DPGstereo said:


> Agree with all of that. Seems the SQ tunes I've been demo'd, suck the life out of the music.


Those were not SQ tunes that you heard, I guess you missed the point I was trying to make.



DPGstereo said:


> Not bashing on class D amps. Again, they have their place. Powered monitors and powered subwoofers are a perfect example. ..... However, I haven't heard any class D that can match the sonic limits of a good class A or A/B.... class A or A/B is sonically more reviling than class D amp.


What makes a powered monitor more suitable for class D? It's still a speaker and amp combo......your Genelec's have three class D amps per cabinet, one for each driver. It's not like only the woofer is running off class D. You are contradicting yourself by by saying that Class A, A/B are more revealing, if that was the case Genelec would not be industry standard in studio monitors. BTW I have heard Genelec and they are excellent.



DPGstereo said:


> Let that guy build two exact vehicles...one class D and other vehicle use say Brax MX4's...which one do you think would win?


The one in which he managed to get a better tune.


----------



## DPGstereo

sqnut said:


> Those were not SQ tunes that you heard, I guess you missed the point I was trying to make.
> 
> 
> 
> What makes a powered monitor more suitable for class D? It's still a speaker and amp combo......your Genelec's have three class D amps per cabinet, one for each driver. It's not like only the woofer is running off class D. You are contradicting yourself by by saying that Class A, A/B are more revealing, if that was the case Genelec would not be industry standard in studio monitors. BTW I have heard Genelec and they are excellent.
> 
> 
> 
> The one in which he managed to get a better tune.



Thank you for the debate. 
Guess I need to further clarify. Believe me, I know exactly what is inside the Genelic speaker. Much research went into the purchase. But they are better suited for a home theater application. Very dynamic, loud and a very forgiving speaker. Hence why recording artist like to hear their mix through them. Kind of rounds out the rough edges in a mix, yet still accurate to the point that if used for mixing reference, that mix will sound good on the majority of listeners systems. 
Example: an average recording will sound good through a Genelic system, play that same average recording through the B&W 802 with solid state McIntosh MC1201's and you hear more of the original recording, good or bad.
This is my experience, over the years. 
I didn't just pull the Genelic theory out of the air. When designing my home theater, I had help from my cousin. He spent 4 years at Berkely School of Music in Boston. Majored in recording engineering. This was there teaching. He taught me a lot about music and the pro-audio side, Pro Tools...

So to answer you question, what makes a monitor suitable for class D? Size. And one could say price, but really size. Price wise- a pair of Genelic 1038B monitors is around a $13,500. B&W 802D are $15,000 pair plus the MC1201's are $20,000 for the pair. And this is really a starter system for the guys serous about 2-channel audio. So price matter for some, not all. There is much more to the pro-audio side, but I don't want to bore you. Meyer seems to be the preferred monitors of current times. Albeit a little more $, but still class D technology.

I do appreciate the spirited debate.




.


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## DPGstereo

I800C0LLECT said:


> This is why we tune....




I've had an Audio Control SA30552 that I've used for years to tune my systems.


----------



## DPGstereo

sqnut said:


> Those were not SQ tunes that you heard, I guess you missed the point I was trying to make.
> 
> 
> 
> What makes a powered monitor more suitable for class D? It's still a speaker and amp combo......your Genelec's have three class D amps per cabinet, one for each driver. It's not like only the woofer is running off class D. You are contradicting yourself by by saying that Class A, A/B are more revealing, if that was the case Genelec would not be industry standard in studio monitors. BTW I have heard Genelec and they are excellent.
> 
> 
> 
> The one in which he managed to get a better tune.




To the statement "those weren't SQ tunes I heard"?
That is exactly what they were. The guys were graciousness enough to let me hear what they were playing for the judges. This particular event had four judges? It was a smaller competition, I admit. But only because of number of attendees. Same points as any event, I was told.




.


----------



## DPGstereo

Who makes the current top-of-the line class D amplifiers?
The sound quality class D amps?
Maybe you guys are talking about amps that I don't know exits?


----------



## DPGstereo

Hillbilly SQ said:


> When I dial in my tonality curve I have the whole bandwidth fairly flat by ear. I don't give a damn what the rta says when it comes to a tonality curve unless I'm hunting for an obnoxious hot spot that needs cut. What I end up with for final curve is what I end up with. I will add heat here and there to enhance the experience. Sub is flat BY EAR from 25-80 as it hands off to the midbass. I need to take a screenshot of my curve and post it. Would probably give the pro's a good laugh. Or make them puke.
> 
> As for the "**** tune", I've heard of people doing it but doubt anyone would openly admit to it. It boggles my mind why someone would sandbag their system unless they're insecure about something. I'm pretty sure most competitors have the black tie tune the judges hear, a tune for driving, and a tune for cutting loose with. The black tie tune is cool to hear just how accurate a car can sound but I want to hear a tune that reflects the owner's personality. For the record I've never competed and quite honestly probably never will. If I did compete it would be for spl.




That's what I've also found out. I use the RTA to get a base line, starting point. Correct for anything out of normal range. Then tune by ear. A flat tune is a boring tune. I wonder if that is the objective of the SQ tune for competition? Honestly, that's what it sounds like to me.

I've also experience that women usually have a good ear for a tune. May not know what or why, but do know if if sounds right or not. Example: after spending hour (too long, senses change) retuning, my wife could come out and listen and tell right away if I was moving in the right direction or not. My piss me off, but more times than not, the next day when I'd listen with fresh ears...she was right.

Women do not like a SQ tune.

*So what is the purpose of a SQ tune?*
They don't accurately reproduce a recording.




.


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## DPGstereo

I tried to be very careful not to offend anyone at the SQ competition. These guys are very serous about their systems. Was told that most guys have a SQ tune and then an very day listening to music setting. And sometimes a more dynamic tune for Rap...ect..or a spl tune.
But no one could explain the reason for the SQ tune? Just is...





.


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## dcfis

what didnt you lie?


----------



## DPGstereo

dcfis said:


> what didnt you lie?




lie?

Did you mean "like"?





.


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## Holmz

dcfis said:


> what didn't you lie?


This is a funny auto correct, considering sound quality and high fidelity.


----------



## DeltaB

When you start defining SQ by the output technology, especially today when some Class D designs easily reach the 0.005% THD+N arena, which surpasses many Class A/B designs of 0.05%, you have to understand a few realities.

One, is many automotive designs over the past few decades have been primarily through-hole designed Class A/B technology that has gone virtually unchanged, from a design perspective, since the 80's. Class D amps over the last decade has made some strides to produce low cost, efficient designs, and we are now seeing some of that coming of age in commercially available avenues.

Two, as I have stated in other threads, the largest Achilles heel of current over-the-counter amps is not it's power or it's Class, but the quality of devices selected in the input stage passing ultimately the entirety of the signal amplified by whatever Class of design. And this one area, above all others, in light of currently available devices can give you the greatest bang for your buck improvements to true sound quality. It's a shame we have 24/192kHz HD content and then pass it through a device that cannot reproduce it with any accuracy, when so many other options are available.


----------



## DPGstereo

DeltaB said:


> When you start defining SQ by the output technology, especially today when some Class D designs easily reach the 0.005% THD+N arena, which surpasses many Class A/B designs of 0.05%, you have to understand a few realities.
> 
> One, is many automotive designs over the past few decades have been primarily through-hole designed Class A/B technology that has gone virtually unchanged, from a design perspective, since the 80's. Class D amps over the last decade has made some strides to produce low cost, efficient designs, and we are now seeing some of that coming of age in commercially available avenues.
> 
> Two, as I have stated in other threads, the largest Achilles heel of current over-the-counter amps is not it's power or it's Class, but the quality of devices selected in the input stage passing ultimately the entirety of the signal amplified by whatever Class of design. And this one area, above all others, in light of currently available devices can give you the greatest bang for your buck improvements to true sound quality. It's a shame we have 24/192kHz HD content and then pass it through a device that cannot reproduce it with any accuracy, when so many other options are available.




I agree, somewhat/mostly, with what you're saying here. Everything does matter. For purpose of this discussion, assume a good quality recording and source. I, personally haven't heard any *class D amplifiers* that can reproduce the fidelity that I'm getting through my _MCC602TM_ (THD 0.005%, S/N 114dB, fully balanced Input/Output, 300 watts x 2 rms) amps. And I do realize that not many are going to go to the extreme of using two of these amplifiers on the front stage alone. I admit it's a little obsessive, I just happen to have two of them from an older install and the room for them.
All I have for a point of reference, for *class D*, is _JL Audio HD 600/4_ and _HD1200/1_. I agree they are fine amplifiers, and seem to be held in high regard by many on this forum. But not in the same ball park of what I hear through these particular *A/B amps*. And no, not all _McIntosh_ amplifiers are designed and sound the same. According to _McIntosh_, these were purposely build to be the best, no cost restraint, car amplifier they could build at the time. And were only available for a short period of time. Not saying, tonally...not talking about specs. I learned a long time ago not to rely on specs. I'm talking about musicality, depth, detail....I'm talking about listening to the crack of a snare drum; the decay, revealing how tight the batter head is, how tight the bottom snare is tightened, single or dual ply coated batter head, wood tip or plastic tip stick..that kind of reveal, with the right recording.
I have alway heard that it really only matters in the higher frequencies, I found that to not be correct in car audio. My installer talked me into a _Mosconi Zero 3_ class *A/B amplifier* to power a single 12" sub. I found it to be more musical than the *class D* _HD1200/1 _on my single 12" sub. Really surprised me to hear what I was actually missing, didn't realize there are so many different tones that can be present in low frequencies. Simple hadn't heard it before. Some recordings more than others of course. In car audio I think we experience, to a degree, something similar to the proximity effect, from speakers being so close. More so than you would if in a larger listening room. Like how the proximity effect can change a vocal with microphone (close adds bass, further away gets thin) or the change in sound you get from a mic'd instrument, depending on how close the mic is to the sound. Not volume..different sound. So being physically close to speakers, and using different amplifiers, may have an even greater effect on sound difference than if in a larger room. This totally contradicts the guy that says "amplifiers don't matter, it's the tune"...sorry, they are just wrong and don't even realize it.

I'm different from a lot of guys I read posting. I don't have a dog in the fight. I'm not promoting one brand over another, just talking technology and design...*class D vs. class A/B*... Just so happens that I have the brands that I do. I'd suspect that _Brax MX2_ may sound even better? Doesn't matter to me, one way or the other. I have been fortunate enough to listen to many systems, from good to elite. I just state what I've heard. My option isn't bias based on price, size ect....

Quick flash back: the _Genelic _system I have referenced, is no doubt a great system, installed properly in a dedicated purpose built home theater. Room sound treatments...When you buy a larger _Genelic system_, part of the purchase includes _Genelic_ sending out a rep/sound technician to help dial in the system. The monitors and subs have a lot of setting for different adjustments (not just gain, freq). _Genelic_, at the time, used one guy to service the southeastern USA. From full blow recording studio's to larger private installs, he was the guy. Turns out, before heading my way, he had just recently been out to Oprah Winfey's home in south FL, had set up her system/home theater. He had no reason to embellish, make up a story. Not bragging in any way here, I have a point. When the tech left my system sounded great. It was right, monitors and subs even have time alignment built in.
Back to c*lass A/B*...I later purchase a pair of _McIntosh MC1201's_ *class A/B* solid state amplifiers (to power a pair of B&W 802D's) from a individual in south Florida. Ivan, people in the know, know who I'm talking about. Went to his home to pick them up..he'd demo'd his home theater system...*class A/B*. All _McIntosh_ gear, including speakers. Main amps were _MC2KW_, these are a 3-piece (2-power modules, 1- output module) mono amp rated at 2,000 watts continuous - 8,000 watts peak. Main speakers _XRT2K_..so basically _McIntosh's_ top of the line *class A/B*. Blew my system away. Unbelievable clarity and musicality. Dynamically, hit you in the chest kick drum with no sense of muddy bass, that seemingly illusive thing. Seems hard to achieve the strong impact without sounding muddy.. But, you didn't just heard/feel the kick, you could hear the pedal contacting the drum head, echo inside drum, start of sound to finish. The level of reveal, for lack of a better word here, was crazy. Like nothing I ever heard before. Far exceeded my _Genelic_ class D system, which before I heard his system, I believed to be close to as good as you can get. Maybe louder, I thought, but sound quality I believed to be as good as it gets...Wrong... Point being, I've had the opportunity to have heard the difference in, close to top-of-the-line, *class D technology vs. class A/B* in a dedicated home theater situation. That along with my personal experiences with some very top end car audio systems had led me to the conclusion that, although *class D* technology has come a long way and certainly has it's advantages, when you talk about purely fidelity, musicality, ability to reveal that n'th degree...*class A/B* *still outperforms* *class D*.





.


----------



## DPGstereo

DC/Hertz said:


> Well the guy that wins everything with class D had MCs before. So that crushes your opinion.




This is the second time you've told me this.

Two things here. I doubt he used the _*MCC602TM*_ amplifiers. May have used _McIntosh_ amps, but *602"s* are a completely different design from anything _McIntosh_ ever built. Plus they are huge in size, built for a short amount of time and not easy to find. So that means for each channel.

Second, tell me what top-of-the-line class D amp that, if all things equal in build/tune are going to sound better than top-of-the-line class A/B?

Take my situation out of the mix, for the sake of discussion. Say he used _*Brax MX4*_ or _*MX2*_ amp. I choose these only because of widely accepted acknowledgement of quality of amp.

Maybe there is a brand of class D amp that I don't know about. Would appreciate the info so I can research it for the next build, coming up shortly. I have _*HD600/4*_ & _*HD1200/1*_ in Jeep TJ. I know that's not what you're talking about.



.


----------



## DeltaB

DPGstereo said:


> I agree, somewhat/mostly, with what you're saying here. Everything does matter. For purpose of this discussion, assume a good quality recording and source. I, personally haven't heard any *class D amplifiers* that can reproduce the fidelity that I'm getting through my _MCC602TM_ (THD 0.005%, S/N 114dB, fully balanced Input/Output, 300 watts x 2 rms) amps. And I do realize that not many are going to go to the extreme of using two of these amplifiers on the front stage alone. I admit it's a little obsessive, I just happen to have two of them from an older install and the room for them.
> All I have for a point of reference, for *class D*, is _JL Audio HD 600/4_ and _HD1200/1_. I agree they are fine amplifiers, and seem to be held in high regard by many on this forum. But not in the same ball park of what I hear through these particular *A/B amps*. And no, not all _McIntosh_ amplifiers are designed and sound the same. According to _McIntosh_, these were purposely build to be the best, no cost restraint, car amplifier they could build at the time. And were only available for a short period of time. Not saying, tonally...not talking about specs. I learned a long time ago not to rely on specs. I'm talking about musicality, depth, detail....I'm talking about listening to the crack of a snare drum; the decay, revealing how tight the batter head is, how tight the bottom snare is tightened, single or dual ply coated batter head, wood tip or plastic tip stick..that kind of reveal, with the right recording.
> I have alway heard that it really only matters in the higher frequencies, I found that to not be correct in car audio. My installer talked me into a _Mosconi Zero 3_ class *A/B amplifier* to power a single 12" sub. I found it to be more musical than the *class D* _HD1200/1 _on my single 12" sub. Really surprised me to hear what I was actually missing, didn't realize there are so many different tones that can be present in low frequencies. Simple hadn't heard it before. Some recordings more than others of course. In car audio I think we experience, to a degree, something similar to the proximity effect, from speakers being so close. More so than you would if in a larger listening room. Like how the proximity effect can change a vocal with microphone (close adds bass, further away gets thin) or the change in sound you get from a mic'd instrument, depending on how close the mic is to the sound. Not volume..different sound. So being physically close to speakers, and using different amplifiers, may have an even greater effect on sound difference than if in a larger room. This totally contradicts the guy that says "amplifiers don't matter, it's the tune"...sorry, they are just wrong and don't even realize it.
> 
> I'm different from a lot of guys I read posting. I don't have a dog in the fight. I'm not promoting one brand over another, just talking technology and design...*class D vs. class A/B*... Just so happens that I have the brands that I do. I'd suspect that _Brax MX2_ may sound even better? Doesn't matter to me, one way or the other. I have been fortunate enough to listen to many systems, from good to elite. I just state what I've heard. My option isn't bias based on price, size ect....
> 
> Quick flash back: the _Genelic _system I have referenced, is no doubt a great system, installed properly in a dedicated purpose built home theater. Room sound treatments...When you buy a larger _Genelic system_, part of the purchase includes _Genelic_ sending out a rep/sound technician to help dial in the system. The monitors and subs have a lot of setting for different adjustments (not just gain, freq). _Genelic_, at the time, used one guy to service the southeastern USA. From full blow recording studio's to larger private installs, he was the guy. Turns out, before heading my way, he had just recently been out to Oprah Winfey's home in south FL, had set up her system/home theater. He had no reason to embellish, make up a story. Not bragging in any way here, I have a point. When the tech left my system sounded great. It was right, monitors and subs even have time alignment built in.
> Back to c*lass A/B*...I later purchase a pair of _McIntosh MC1201's_ *class A/B* solid state amplifiers (to power a pair of B&W 802D's) from a individual in south Florida. Ivan, people in the know, know who I'm talking about. Went to his home to pick them up..he'd demo'd his home theater system...*class A/B*. All _McIntosh_ gear, including speakers. Main amps were _MC2KW_, these are a 3-piece (2-power modules, 1- output module) mono amp rated at 2,000 watts continuous - 8,000 watts peak. Main speakers _XRT2K_..so basically _McIntosh's_ top of the line *class A/B*. Blew my system away. Unbelievable clarity and musicality. Dynamically, hit you in the chest kick drum with no sense of muddy bass, that seemingly illusive thing. Seems hard to achieve the strong impact without sounding muddy.. But, you didn't just heard/feel the kick, you could hear the pedal contacting the drum head, echo inside drum, start of sound to finish. The level of reveal, for lack of a better word here, was crazy. Like nothing I ever heard before. Far exceeded my _Genelic_ class D system, which before I heard his system, I believed to be close to as good as you can get. Maybe louder, I thought, but sound quality I believed to be as good as it gets...Wrong... Point being, I've had the opportunity to have heard the difference in, close to top-of-the-line, *class D technology vs. class A/B* in a dedicated home theater situation. That along with my personal experiences with some very top end car audio systems had led me to the conclusion that, although *class D* technology has come a long way and certainly has it's advantages, when you talk about purely fidelity, musicality, ability to reveal that n'th degree...*class A/B* *still outperforms* *class D*..


I've been in audio since tubes. Current through-hole MOSFET Class D design does not lend itself to the quality Class D can deliver. However, surface mount designs and newer eGaN FET-based Class D amplifiers switch many times faster than most power MOSFETs and do not have any reverse recovery charge. As a result, the dead-time typically 25 ns for silicon power MOSFETs can be reduced by 80%, to 5 ns or less, lending itself to better than Class A performance, without the complexity or inefficiency.

Why We'll Soon Be Living In A Class D World - Audiophile Review

If you are listening to audio in a vehicle at sound levels that come close to the gargantuan power levels your claiming, than you're either not real bright, or stone deaf.


----------



## Holmz

DPGstereo said:


> ...
> Second, tell me what top-of-the-line class D amp that, if all things equal in build/tune are going to sound better than top-of-the-line class A/B?
> ...


Two amps with 0% THD and 120+ dB of SNR would be the same no matter if they were class A, A/B, (O-negative) or class D.
A perfect amp would not care what class, or caste system, it was from.



These words seem like sage advice:



DC/Hertz said:


> Sure I'll waste some of my time.
> Do you know what sound quality is? Well it's not a specific amp topology that shouldn't be coloring anything.
> It's getting rid of all the rattles in the interior
> It's getting the sub and mid bass in phase and blended
> It's getting delay right so you get a stage
> It's getting a good response curve from all the crazy stuff the interior is doing to it.
> It's getting a stable curve so the imaging doesn't smear and you get some layering.
> 
> Nothing that matters cares what type of amp is used.
> That is black and white.


----------



## I800C0LLECT

DPGstereo said:


> I've had an Audio Control SA30552 that I've used for years to tune my systems.


But you asked specifically... What is an SQ tune and why? The "SQ" will always be argued but the reason for tuning was answered with the measured response in and out of the car.

What do you use to measure? How many measurements do you take? Having tools is great. But what problems are you correcting with them?


----------



## DPGstereo

DeltaB said:


> I've been in audio since tubes. Current through-hole MOSFET Class D design does not lend itself to the quality Class D can deliver. However, surface mount designs and newer eGaN FET-based Class D amplifiers switch many times faster than most power MOSFETs and do not have any reverse recovery charge. As a result, the dead-time typically 25 ns for silicon power MOSFETs can be reduced by 80%, to 5 ns or less, lending itself to better than Class A performance, without the complexity or inefficiency.
> 
> Why We'll Soon Be Living In A Class D World - Audiophile Review
> 
> If you are listening to audio in a vehicle at sound levels that come close to the gargantuan power levels your claiming, than you're either not real bright, or stone deaf.





Specs don't always translate into real world performance. I keep asking, *what is a go to class D amp I can compare to?* You may very well be correct?


Have you ever had a system with a lot of headroom?
When listening to dynamic music, especially at higher volumes (not crazy loud) and you come to short burst very dynamic sounds...and you system still plays that portion cleanly, with extra headroom. That's what makes a difference.



I was listening to a Celine Deon song the other day..Power Of Love..I think, just because it sounded so good, very dynamic song. I heard things that I've never heard in that song. Chances are that the most dynamic portions of the song were probably slightly clipping in past systems. May not like the song, but Wow...



.


----------



## DPGstereo

I800C0LLECT said:


> But you asked specifically... What is an SQ tune and why? The "SQ" will always be argued but the reason for tuning was answered with the measured response in and out of the car.
> 
> What do you use to measure? How many measurements do you take? Having tools is great. But what problems are you correcting with them?




All stems from a SQ competition I recently attended. I listen to what they were playing for the Judges. Sounded terrible. Systems were nice, it was the tune they all had. What is the goal of a SQ tune in a competition?
It's obviously not for music enjoyment. 
First one I demo'd the guy said "you're not going to like this, it's a SQ tune"? He knew I had never attended a SQ competition. 



.


----------



## DC/Hertz

Have you ever considered you don't know what a good tune is? 
I use my comp tune daily and love it.


----------



## DeltaB

DPGstereo said:


> Specs don't always translate into real world performance. I keep asking, *what is a go to class D amp I can compare to?* You may very well be correct?
> 
> Have you ever had a system with a lot of headroom?
> When listening to dynamic music, especially at higher volumes (not crazy loud) and you come to short burst very dynamic sounds...and you system still plays that portion cleanly, with extra headroom. That's what makes a difference.
> 
> I was listening to a Celine Deon song the other day..Power Of Love..I think, just because it sounded so good, very dynamic song. I heard things that I've never heard in that song. Chances are that the most dynamic portions of the song were probably slightly clipping in past systems. May not like the song, but Wow....


Again, let me assure you, I'm not a neophyte to the industry. I've been a licensed FCC operator in the radio spectrum since the 70's, and was at Altec-Lansing in the production and engineering department from the late 80's until Mark IV Industries sold the brand to the Chinese in the late 90's.

Concerning some "go-to" cheapo over on Sonic or Crutchfield for newer designs, sadly, you and I are still stuck with 80's through-hole designs, and I stated as much in my earlier post. However, TI, NXP, EPC as well others who have reference design boards out there, and you simply have to stuff the board. It's not that it doesn't exist, it certainly does.

Again, if you are attempting to tell me 8kW of headroom is being utilized inside your vehicle with you in it, then you are either kidding yourself, and don't know any better, or you have no hearing and can only feel induced sound through percussion waves, because 8kW of dynamic power at only a few feet, in a near-field response will promote instant and permanent hearing loss.


----------



## ca90ss




----------



## DeltaB

ca90ss said:


>


Well, not so fast here... it really isn't a dead horse. It's making the most of what is available. That's why I say, in current through-hole designs, the one area that needs attention, and could benefit the most is the input section.


----------



## brumledb

It's a dead horse because it (Class A/B vs Class D) has been discussed adnauseam in many, many threads. 


Sent from my iPhone using Tapatalk


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## DPGstereo

DeltaB said:


> Again, let me assure you, I'm not a neophyte to the industry. I've been a licensed FCC operator in the radio spectrum since the 70's, and was at Altec-Lansing in the production and engineering department from the late 80's until Mark IV Industries sold the brand to the Chinese in the late 90's.
> 
> Concerning some "go-to" cheapo over on Sonic or Crutchfield for newer designs, sadly, you and I are still stuck with 80's through-hole designs, and I stated as much in my earlier post. However, TI, NXP, EPC as well others who have reference design boards out there, and you simply have to stuff the board. It's not that it doesn't exist, it certainly does.
> 
> Again, if you are attempting to tell me 8kW of headroom is being utilized inside your vehicle with you in it, then you are either kidding yourself, and don't know any better, or you have no hearing and can only feel induced sound through percussion waves, because 8kW of dynamic power at only a few feet, in a near-field response will promote instant and permanent hearing loss.




No. The amps are a true 300 watts rms per channel. I'm using two amps on a Focal No 7, 3-way, with Crossblock crossover. Crossover allows for bi-amping. So 6.5" mid-woofers located in doors get one channel of 300 watts, and the 3" and tweeter get the other channel of 300 watts. Due to Crossblock crossover allowing bi-amp wiring. I used the large amp on the 3' and tweeter just for dampening factor and design of amplifier. They are extremely quite amplifiers. All for sound quality.
I would rarely play system over 110 decibels.

Which is close to the level of my acoustic drum set 105dB

..


----------



## DPGstereo

DC/Hertz said:


> Have you ever considered you don't know what a good tune is?
> I use my comp tune daily and love it.




No. Not really. I listen daily to B&W 802D's with good amps. Once use to that, quickly pick up on a bad tune. Or use a good set of headphones to use as a tonal reference. 

I seriously doubt your tune is what I heard. I certainly don't want to offend anyone. Just unsure of the goal of a SQ tune, in competition?


What would you consider a good or best sounding class D amp that I could give a listen?



Can't seem to get an answer to that? Probably amps I don't know about.




.


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## I800C0LLECT

"SQ" really just denotes the difference between your Craigslist install and somebody who's applying a thought process to their system response. I don't know anybody gets hung up on that.

Some guys use logic 7 for rear speakers. Some use arrays...etc


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## ca90ss

DPGstereo said:


> No. Not really. I listen daily to B&W 802D's with good amps. Once use to that, quickly pick up on a bad tune. Or use a good set of headphones to use as a tonal reference.
> 
> I seriously doubt your tune is what I heard. I certainly don't want to offend anyone. Just unsure of the goal of a SQ tune, in competition?
> 
> 
> What would you consider a good or best sounding class D amp that I could give a listen?
> 
> 
> 
> Can't seem to get an answer to that? Probably amps I don't know about.
> 
> 
> 
> 
> .


When you compare amplifiers how do you set them up before comparing them?


----------



## DC/Hertz

DPGstereo said:


> No. Not really. I listen daily to B&W 802D's with good amps. Once use to that, quickly pick up on a bad tune. Or use a good set of headphones to use as a tonal reference.
> 
> I seriously doubt your tune is what I heard. I certainly don't want to offend anyone. Just unsure of the goal of a SQ tune, in competition?
> 
> 
> What would you consider a good or best sounding class D amp that I could give a listen?
> 
> 
> 
> Can't seem to get an answer to that? Probably amps I don't know about.
> 
> 
> 
> 
> .


I don't listen to amps. I use what fits with the most power I can get. 
It appears you don't have any way to eliminate the car so that's what you are hearing.


----------



## DPGstereo

ca90ss said:


> When you compare amplifiers how do you set them up before comparing them?





I completely understand where you're going with that. I do understand how to setup a system.

What is considered a hi-end class D amp? General consensus of who makes a great sounding full-range Class-D amp?

Example, I think many would agree that the Brax MX4 is a hi-end, Class A/B, great sounding full-range amp.



.


----------



## DC/Hertz

Class D is cheaper to build. 
Which doesn't make much since because A/B is the same as it has been for decades where as Class D continues to advance. Both is power and size and efficiency.


----------



## ca90ss

DPGstereo said:


> I completely understand where you're going with that. I do understand how to setup a system.
> 
> What is considered a hi-end class D amp? General consensus of who makes a great sounding full-range Class-D amp?
> 
> Example, I think many would agree that the Brax MX4 is a hi-end, Class A/B, great sounding full-range amp.
> 
> 
> 
> .


The reason I ask is it doesn't matter what anyone recommends if you're not going to do a proper comparison.


----------



## DPGstereo

DC/Hertz said:


> I don't listen to amps. I use what fits with the most power I can get.
> It appears you don't have any way to eliminate the car so that's what you are hearing.





Ok, sounds like you know what you're doing.

Say you were going to build a system to compete in SQ competition for a customer or yourself?...

Say, for purpose of discussion a Ram quad cab truck. And customer requested you to use Class-D amplifiers. No price limitations on gear or install. Or if we need a spending limit, lets say $25,000 total.


For sake of discussion they say that you pick the speakers, head unit, dsp..


*What Class-D amplifiers do you choose to install and tune for the best possible outcome?*





.


----------



## DPGstereo

DC/Hertz said:


> Class D is cheaper to build.
> Which doesn't make much since because A/B is the same as it has been for decades where as Class D continues to advance. Both is power and size and efficiency.




We can get there. I have faith..



..


----------



## DC/Hertz

DPGstereo said:


> Ok, sounds like you know what you're doing.
> 
> Say you were going to build a system to compete in SQ competition for a customer or yourself?...
> 
> Say, for purpose of discussion a Ram quad cab truck. And customer requested you to use Class-D amplifiers. No price limitations on gear or install. Or if we need a spending limit, lets say $25,000 total.
> 
> 
> For sake of discussion they say that you pick the speakers, head unit, dsp..
> 
> 
> *What Class-D amplifiers do you choose to install and tune for the best possible outcome?*
> 
> 
> 
> 
> 
> .


No system should ever need to cost $25k. $5k is plenty. 
But I will always choose the brand I want to support because they offer me the best support. 
Of course a cheap amp is a cheap amp. No matter the topology. 
The way you are talking says a boss audio level A/B is better then any class D. 
Which the 25 watts the boss will make sounds like 25 watts of anything else. 
It will just fall apart and suck current.


----------



## DPGstereo

DC/Hertz said:


> No system should ever need to cost $25k. $5k is plenty.
> But I will always choose the brand I want to support because they offer me the best support.
> Of course a cheap amp is a cheap amp. No matter the topology.
> The way you are talking says a boss audio level A/B is better then any class D.
> Which the 25 watts the boss will make sounds like 25 watts of anything else.
> It will just fall apart and suck current.





For sake of discussion, the price of the amp has no limit.
One question.

*What is the best sounding SQ Class-D full-range amplifier you know of?*





.


----------



## DPGstereo

.


I don't get it?

I surrender to one question...


I've asked same questions as many different ways as I can think of. All I get is either condescending commits or basically insinuation that that I don't know what I'm talking about or I don't know what a good tune is, or dead horse commit? 
When really the answers I'm getting are deflecting from the questions that are being asked, for some reason. Forget my equipment list.




Many have been quick to tell me how Class-D is the way to go and their opinion of why, but won't back it up by telling me one *Class-D amp would they consider hi-end/ SQ?* 

*I'm simply asking, what amps are you taking about that I could consider?*



Sereno: You're the installer asked to build a hi-end, SQ build to win SQ competitions. Budget is up to $25,000. Vehicle is a newer style F150, crew cab.
Installer picks speakers, head unit, sound deadening, dsp, system design. Only request is that the amplifiers used be *Class-D design*, but the objective is best sound quality. Any brand?
*What amps would you suggest?*



.


----------



## DPGstereo

DC/Hertz said:


> No system should ever need to cost $25k. $5k is plenty.
> But I will always choose the brand I want to support because they offer me the best support.
> Of course a cheap amp is a cheap amp. No matter the topology.
> The way you are talking says a boss audio level A/B is better then any class D.
> Which the 25 watts the boss will make sounds like 25 watts of anything else.
> It will just fall apart and suck current.




No offense, but from asking around, the install alone will be $10,000 or more from a professional installer. For this kind of build.




.


----------



## ca90ss

DPGstereo said:


> *What amps would you suggest?*


There is no magic amp that anyone can recommend that will change your bias against class d.


----------



## DPGstereo

ca90ss said:


> There is no magic amp that anyone can recommend that will change your bias against class d.




I don't have anything against Class-D amps. Recently purchased two.

Truth is, comments have been made by folks that have a bias for Class D. My suspension is it's more of a $ thing. Maybe size, but truthfully money by a lot of the comments I've seen.

No one has designed a class D amp that has the sound quality of the top-of the-line AB amps like Mosconi, Brax ect...

Can't believe no one will just state the obvious.



.


----------



## ca90ss

That's because the whole concept of amps having sq is stupid to begin with.


----------



## DPGstereo

ca90ss said:


> That's because the whole concept of amps having sq is stupid to begin with.




SQ is just the term being used. I'm talking about what really sounds better.
I'm fairly certain that most believe, if they are being honest that different quality amplifiers effect the sound. However I have heard a couple try to push their "being right" opinion to say amps don't matter? Really?

Unfortunately for them, they haven't had the opportunity to listen to the systems I have. I really hope they get to, some day, if truly a fan of audio.


----------



## sqnut

DPGstereo said:


> I've had an Audio Control SA30552 that I've used for years to tune my systems.


That's an RTA, what were you using for processing?


----------



## DPGstereo

sqnut said:


> That's an RTA, what were you using for processing?



I think you're just messing with me..haha.. but cool..

Mosconi 6to8 Areospace 



.


----------



## sqnut

DPGstereo said:


> I think you're just messing with me..haha.. but cool..
> 
> Mosconi 6to8 Areospace
> 
> 
> 
> .


Tell us a bit about how you used the 3052, not the 30552 and the 6 to 8 to tune your car. What was your tuning process?


----------



## DeltaB

DPGstereo said:


> No. The amps are a true 300 watts rms per channel. I'm using two amps on a Focal No 7, 3-way, with Crossblock crossover. Crossover allows for bi-amping. So 6.5" mid-woofers located in doors get one channel of 300 watts, and the 3" and tweeter get the other channel of 300 watts. Due to Crossblock crossover allowing bi-amp wiring. I used the large amp on the 3' and tweeter just for dampening factor and design of amplifier. They are extremely quite amplifiers. All for sound quality.
> I would rarely play system over 110 decibels.
> 
> Which is close to the level of my acoustic drum set 105dB.


Just be mindful when it comes to damping factor, it really is only applicable at frequencies 100~150Hz and below. Tweeters have so little mass and excursion, damping factor is of no relevance, however, you do want to insure tweeters are mounted solidly to prevent very minute movement to eliminate high frequency smearing.

I, not unlike you, have a love affair with audio, and am certainly aware of how slow the automotive market has been to adopt some of the newer designs that are out there. But that does not mean that as Class D designs continue to overcome the technology hurdles, that by reason of it being a Class D inherently means poor performance. Let's hope we can see emerging in the market a manufacturer who will start to leverage some of these newer designs for automotive use. It's already emerged in the home audio market, like this;

Stereo Power Amplifier SE-R1 | Reference Class R1 Series | Technics US

https://www.pioneerelectronics.com/PUSA/Home/D3#power-evolved


----------



## I800C0LLECT

I think it always comes back to the same question... Can you hear the difference? You can debate install details and never get anywhere. Set up your own true blind comparison and you'll have your answer


----------



## DeltaB

I800C0LLECT said:


> I think it always comes back to the same question... Can you hear the difference? You can debate install details and never get anywhere. Set up your own true blind comparison and you'll have your answer


I've been involved in blind study tests more times than I want to count. I used a low cost Class D solution ($200) for my Jag when I decided to update it's audio, and the problems with its audio quality didn't reside in its output technology, but in the low quality input section. Once that was changed, there is a marked difference. Audible, viewable, and repeatable. And to be honest, the results of blind tests will be determined by the subjective view of the listener, and the less experienced they are, they more subjective the results. When you stack the deck for the test, your results will reveal some strange outcomes, with no real consistencies.

When it comes to accuracy, just superimpose the output over the input signal, or dump it into a Lissajous pattern. The tonality of a given design is most affected by the quality of the signal path devices, both passive and active, that you pass it through. That's how you can achieve a much greater listening experience, and how a few simple upgrades can make a so-so sounding amp, come alive with a greater soundstage, better tonality and much more accurate reproduction of the original input signal.


----------



## I800C0LLECT

The results are repeatable. Out of the box they sound different. But you can set gains and other variables to where you can't tell the difference between amps. So which road do you take? If you can prove class D sounds different then do it and post results. Nobody has been able to make that tangible...If you're telling us you can "hear" the difference then that's you prerogative.

Most in this forum don't care about topology. If it's a quality build they believe they have enough tools to manipulate the sound to be whatever they want. With that said, they choose equipment based on priority, convenience, and install requirements.

You just said you can identify differences in signal output between two devices through measurements.

At this point, what are you questioning or trying to resolve? Are you telling us that you've identified differences in output between two amps when superimposed as stated above?

At the end of the day nobody cares if you can hear a difference. Why? Because of those images I posted showing what the environment does to response. If you're telling us you can make those differences tangible with evidence... That's awesome. Can you share that data?


----------



## DeltaB

I800C0LLECT said:


> The results are repeatable. Out of the box they sound different. But you can set gains and other variables to where you can't tell the difference between amps. So which road do you take? If you can prove class D sounds different then do it and post results. Nobody has been able to make that tangible...If you're telling us you can "hear" the difference then that's you prerogative.


When the signal path cannot faithfully reproduce the input, then it is axiomatic it will never sound the same twice. That's my point. There is no guarantee that any two over-the-counter amps utilize the same components. Obviously it will sound different from A/B testing. You just shot your argument in the foot. Tangible is comparing the input against it's output, both at the driver stage and the output stage. And again, the input stage of virtually every over-the-counter low cost amp is plagued with this, and the best place to start for truly repeatable and marked results.



> Most in this forum don't care about topology. If it's a quality build they believe they have enough tools to manipulate the sound to be whatever they want. With that said, they choose equipment based on priority, convenience, and install requirements.


The problem you should start with is a solid base to minimize changing or manipulating the original signals in the signal path. All you add is more noise in bus gain structure and introduce more THD+N. The shortest path from the DAC or volume controller is always the best path. Again, axiomatic.



> You just said you can identify differences in signal output between two devices through measurements.
> 
> At this point, what are you questioning or trying to resolve? Are you telling us that you've identified differences in output between two amps when superimposed as stated above?


Get a low-cost probe and you can use a laptop as an oscilloscope. For me, I still use my Tektronix.



> At the end of the day nobody cares if you can hear a difference. Why? Because of those images I posted showing what the environment does to response. If you're telling us you can make those differences tangible with evidence... That's awesome. Can you share that data?


Nobody cares? hmmmm... self defeating arguments now? 

The image you posted from Harmon in prior posts really have no relevance in the design of the amp, or it's signal, but the proximity affect and near-field response of reflected sound found inside a vehicle. That's a non-sequitur to the subject. That's like saying, "you start a car by placing the key in the ignition and turning it until the starter motor begins to turn, ipso fact, or by reason thereof, ground cheese tastes great on pizza!"


----------



## I800C0LLECT

All you're doing is arguing theory. I plainly stated what most focus on in this forum... The end response.

You are the one asking us to defend an argument you made. Nobody cares. We care about real world response. The car dictates that above all. There's way to many pages discussing that already.

You're beating a dead horse


----------



## Holmz

DeltaB said:


> ...
> When it comes to accuracy, just superimpose the output over the input signal, or dump it into a Lissajous pattern. The tonality of a given design is most affected by the quality of the signal path devices, both passive and active, that you pass it through. That's how you can achieve a much greater listening experience, and how a few simple upgrades can make a so-so sounding amp, come alive with a greater soundstage, better tonality and much more accurate reproduction of the original input signal.


That is a lot of descriptors.

How does one amp with 0.005% THD differ in "soundstage, tonality, coming aliveness, more accuracy"... from another amp with the same 0.005% THD?

How do these Lissajous patterns differ when they are both at the verge of perfection?


----------



## sqnut

I800C0LLECT said:


> The results are repeatable.


The result is repeatable if the methodology is sound AND the ears listening are trained, I think that is the point being made and it's cent-percent true.


----------



## DeltaB

Holmz said:


> That is a lot of descriptors.
> 
> How does one amp with 0.005% THD differ in "soundstage, tonality, coming aliveness, more accuracy"... from another amp with the same 0.005% THD?
> 
> How do these Lissajous patterns differ when they are both at the verge of perfection?


You're asking me to compare THD+N to tonality. Tonality is affected greatly by the passive devices, especially electrolytics. in fact their microphonic. Are you actually asking a serious question here? (SMH) Just how long have you been in the audio industry?


----------



## ca90ss

DeltaB said:


> You're asking me to compare THD+N to tonality. Tonality is affected greatly by the passive devices, especially electrolytics. in fact their microphonic. Are you actually asking a serious question here? (SMH) Just how long have you been in the audio industry?


So what measureable, audible parameter do you find to be lacking in modern car amps?


----------



## DeltaB

ca90ss said:


> So what measureable, audible parameter do you find to be lacking in modern car amps?


Input buffer section. On so many levels. And the greatest point of improvement on almost every car audio amp out there.


----------



## ca90ss

DeltaB said:


> Input buffer section. On so many levels. And the greatest point of improvement on almost every car audio amp out there.


What specific audible measurement/s will be improved by making changes to that part of the amp?


----------



## DeltaB

ca90ss said:


> What specific audible measurement/s will be improved by making changes to that part of the amp?


In the case of mine, NVX had (and does across the board on it's line of amps) utilized TL072s as the input buffer. I utilized much newer DI process laser-trimmed Burr-Brown OPA1642s. The electrolytics were changed to ELNA SILMIC IIs. The greatest improvement was in phase control. The TL072 will slam into phase inversion when you get close to the rails. TL072s have no place in audio equipment in light of the choices we have out there on the market today. One need only look at the THD+N on the TL072 as it increases drastically as you move up the audio spectrum. I prefer one that is not only phase stable, but THD+N stays constant across the spectrum. TI compares these two devices in their datasheet on the OPA1642. You're free to go see for yourself. TI also recommends this as a drop in replacement, so you don't have to redesign the circuit. TL072s are noisy, slow, overshoot excessively and phase issues at higher levels.

Virtually every single amp I've opened in the last decade, both auto and home, can be improved with careful selection of more modern designs available to the mass market.


----------



## sqnut

ca90ss said:


> What specific audible measurement/s will be improved by making changes to that part of the amp?


There are only three ways we 'hear a difference', through differences in timing, response or phase. Differences in speakers, amps etc have to exhibit a difference in one or more of the three. Two amps will sound the same if they measure the same, at the resolution we hear at. 

Amps that measure the same at say 1db resolution can sound different because the lay ears can probably tell a difference at +/-0.5db, trained ones at +/- 0.1 db. Same with timing, we can tell a difference at 0.01 ms, so we need to measure latency between channels at that level etc.


----------



## DeltaB

sqnut said:


> There are only three ways we 'hear a difference', through differences in timing, response or phase. Differences in speakers, amps etc have to exhibit a difference in one or more of the three. Two amps will sound the same if they measure the same, at the resolution we hear at.
> 
> Amps that measure the same at say 1db resolution can sound different because the lay ears can probably tell a difference at +/-0.5db, trained ones at +/- 0.1 db. Same with timing, we can tell a difference at 0.01 ms, so we need to measure latency between channels at that level etc.


I'm not sure where you glean this data from. Can you cite the source?


----------



## ca90ss

sqnut said:


> There are only three ways we 'hear a difference', through differences in timing, response or phase. Differences in speakers, amps etc have to exhibit a difference in one or more of the three. Two amps will sound the same if they measure the same, at the resolution we hear at.
> 
> Amps that measure the same at say 1db resolution can sound different because the lay ears can probably tell a difference at +/-0.5db, trained ones at +/- 0.1 db. Same with timing, we can tell a difference at 0.01 ms, so we need to measure latency between channels at that level etc.


Yes, I know these things. The reason I asked the question is in these threads inevitably someone always comes in with some magic spec or part that they claim is the reason amps sound different whether it be damping factor or slew rate or opamps or capacitors or whatever else. I just wanted to know what his magic part/measurement was. The good news is I just happen to have an amp that I recently replaced all of the caps in the audio path with SILMIC lls and replaced the TL 072s with OPA 1642s and since I socketed the opamps when I did it it's not hard to swap back and forth between the two. So if I can figure out an easy way to measure phase I can see what the differences are for myself and whether those differences are enough to be audible.


----------



## DeltaB

ca90ss said:


> Yes, I know these things. The reason I asked the question is in these threads inevitably someone always comes in with some magic spec or part that they claim is the reason amps sound different whether it be damping factor or slew rate or opamps or capacitors or whatever else. I just wanted to know what his magic part/measurement was. The good news is I just happen to have an amp that I recently replaced all of the caps in the audio path with SILMIC lls and replaced the TL 072s with OPA 1642s and since I socketed the opamps when I did it it's not hard to swap back and forth between the two. So if I can figure out an easy way to measure phase I can see what the differences are for myself and whether those differences are enough to be audible.


Concerning socketing and then placing ultra-low distortion op-amps on a riser board to adapt DIP to SOIC and then place them in a socket, you can run yourself off the road. Primarily, because of lead length, (and its capacitance) and the inability to decouple the input to the ground plane close enough to the device to take advantage of its performance. I have yet to see any adapter that can provide a grounded plane to decouple from, since no lead of the 8 pin DIP adapter provide one. This is one reason why Zapco uses AD OP275s in their Z-LX amps, (which is a through hole DIP design) and while the device is very close in it's overall performance, it's noise, THD and CMRR suffer because of its DIP packaging. Its also one of the things that TI themselves will warn you against doing.

But, as TI says, "Audio enthusiast will do what they do..." and concerning DIP to SOIC adaptions, "Some may involve adapting to smaller, more modern package types, and these physical adaptations can, in some circuits, cause problems such as oscillations."


----------



## ca90ss

There were no signs of oscillation but I'm sure if my results aren't what you expect you can come up with a myriad of other ways I've sinned against the audio gods that caused me to get the results I got. If it makes you feel better I'm sure somewhere around here I have two of the same model amp that use soic 072s that I can swap out for 1642s in one of them to compare.


----------



## DeltaB

ca90ss said:


> There were no signs of oscillation but I'm sure if my results aren't what you expect you can come up with a myriad of other ways I've sinned against the audio gods that caused me to get the results I got. If it makes you feel better I'm sure somewhere around here I have two of the same model amp that use soic 072s that I can swap out for 1642s in one of them to compare.


That's rather presumptuous. If you don't understand what was said, or the reason you need to decouple close to the device, then maybe you should educate yourself on circuit design, decoupling principles, and actually listen to what the device manufacturer is telling you. I don't have time for ignorance calling itself "knowledge."

From Analog Devices: What is proper decoupling. Key aspects of proper decoupling are;

A smaller cap (typ. 0.01 μF – 0.1 μF) as physically close to the power pins
of the chip as is possible. 

The purpose of this capacitor is to short the high frequency noise
away from the chip. (long lead length of over a few millimeters negates it)
All decoupling capacitors should connect to a large area low impedance
ground plane through a via or short trace to minimize inductance. (no path to ground negates the purpose of decoupling)


----------



## Holmz

DeltaB said:


> ...Are you actually asking a serious question here? (SMH)...


Not really, I am suggesting that your smorgasbord (SB) of descriptors is an anagram for what seems like general BS. Either that or I do not understand, hence the questions.
It is a serious question of how two perfect amps differ?



DeltaB said:


> You're asking me to compare THD+N to tonality. Tonality is affected greatly by the passive devices, especially electrolytics. in fact their microphonic.


Is it measurable?
Are you suggesting that everyone pull their amps apart to replace the passive components?




DeltaB said:


> ... (SMH) Just how long have you been in the audio industry?


Your argument from authority approach sounds good, but so far you have not conveyed any authority on the subject.
I am really not interested in your qualifications, I just want to know how two perfect amplifiers can actually be different without use of every buzzword known to mankind.


----------



## DeltaB

Holmz said:


> Not really, I am suggesting that your smorgasbord (SB) of descriptors is an anagram for what seems like general BS. Either that or I do not understand, hence the questions.
> It is a serious question of how two perfect amps differ?
> 
> Is it measurable?
> Are you suggesting that everyone pull their amps apart to replace the passive components?
> 
> Your argument from authority approach sounds good, but so far you have not conveyed any authority on the subject.
> I am really not interested in your qualifications, I just want to know how two perfect amplifiers can actually be different without use of every buzzword known to mankind.


THD+N is a measurement of what a given device will add to the bus gain structure, and in the end the original signal. This is why devices like op amps have this measurement. It itself colors the sound. What you are asking is can or will 2 amps from differing manufacturers who have a total THD+N level of 0.05% sound different. Answer is simple, yes. Why? A number of factors, which starts with each device in the signal chain from the source to outputs. Signal chain passive components contribute to it's sound qualities and can be quite different, even though a rated THD+N may be close to the same.

If you have issues with what I'm saying, there is a ton of materials over decades of time concerning this subject. Do your own homework.


----------



## I800C0LLECT

If there a .05% difference that is measured... Does that overshadow the environment? Will that difference be audible in a double blind test?


----------



## Holmz

DeltaB said:


> THD+N is a measurement of what a given device will add to the bus gain structure, and in the end the original signal. This is why devices like op amps have this measurement. It itself colors the sound. What you are asking is can or will 2 amps from differing manufacturers who have a total THD+N level of 0.05% sound different. Answer is simple, yes. Why? A number of factors, which starts with each device in the signal chain from the source to outputs. Signal chain passive components contribute to it's sound qualities and can be quite different, even though a rated THD+N may be close to the same.
> 
> If you have issues with what I'm saying, there is a ton of materials over decades of time concerning this subject. Do your own homework.


Easy there sport.

My point is that as THD + N goes to 0.005% and if it goes to zero, then there will be no colouration.

The second point is that speakers can commonly have between -20 and -40 dB of Distortion.
-20dB is 1%
-30dB is 0.1%
And -40dB is 0.01%

Therefore I am failing to see how two amplifiers with 0.005% THD+N would be able to sound much different through the same speakers, unless those speakers were much closer to perfect than what is commonly available, and commonly used.


----------



## DC/Hertz

DeltaB said:


> THD+N is a measurement of what a given device will add to the bus gain structure, and in the end the original signal. This is why devices like op amps have this measurement. It itself colors the sound. What you are asking is can or will 2 amps from differing manufacturers who have a total THD+N level of 0.05% sound different. Answer is simple, yes. Why? A number of factors, which starts with each device in the signal chain from the source to outputs. Signal chain passive components contribute to it's sound qualities and can be quite different, even though a rated THD+N may be close to the same.
> 
> If you have issues with what I'm saying, there is a ton of materials over decades of time concerning this subject. Do your own homework.


There is also a ton of material from decades that show amps don't sound different. Which includes my ears.


----------



## ca90ss

DeltaB said:


> That's rather presumptuous. If you don't understand what was said, or the reason you need to decouple close to the device, then maybe you should educate yourself on circuit design, decoupling principles, and actually listen to what the device manufacturer is telling you. I don't have time for ignorance calling itself "knowledge."
> 
> From Analog Devices: What is proper decoupling. Key aspects of proper decoupling are;
> 
> A smaller cap (typ. 0.01 μF – 0.1 μF) as physically close to the power pins
> of the chip as is possible.
> 
> The purpose of this capacitor is to short the high frequency noise
> away from the chip. (long lead length of over a few millimeters negates it)
> All decoupling capacitors should connect to a large area low impedance
> ground plane through a via or short trace to minimize inductance. (no path to ground negates the purpose of decoupling)


I'm aware of the possibility of oscillation, but in my case there's no evidence of it. While it may not be the ideal textbook implementation I don't see what the problem is if it works.


----------



## DeltaB

DC/Hertz said:


> There is also a ton of material from decades that show amps don't sound different. Which includes my ears.


Please try selling this non-sense to someone who doesn't know any better. I'm not interested.


----------



## DeltaB

ca90ss said:


> I'm aware of the possibility of oscillation, but in my case there's no evidence of it. While it may not be the ideal textbook implementation I don't see what the problem is if it works.


As long as you are aware of the pitfalls. Switching supplies, and hash from PWM if a Class D amp, can introduce itself from the supply, and in frequencies outside or above the audible spectrum can set itself up to be introduced in to the final section. This can become very problematic in Class D operation. I would check upwards to 1mHz for indications of oscillations on the output of the buffer circuit before placing it in service.

Grounding and Decoupling: Learn Basics Now and Save Yourself Much Grief Later! Part 2: Decoupling | Analog Devices


----------



## DeltaB

Holmz said:


> Easy there sport.
> 
> My point is that as THD + N goes to 0.005% and if it goes to zero, then there will be no colouration.
> 
> The second point is that speakers can commonly have between -20 and -40 dB of Distortion.
> -20dB is 1%
> -30dB is 0.1%
> And -40dB is 0.01%
> 
> Therefore I am failing to see how two amplifiers with 0.005% THD+N would be able to sound much different through the same speakers, unless those speakers were much closer to perfect than what is commonly available, and commonly used.


So far, you've been unable to understand, or intentionally discounting the relationship and influence of passive devices throughout the analog path to the reproduction of audio signals. Your assertions make no sense in contrast to the questions you are asking. Good luck in your search for understanding.


----------



## DC/Hertz

DeltaB said:


> Please try selling this non-sense to someone who doesn't know any better. I'm not interested.


But what about the BS you are selling?


----------



## DeltaB

I800C0LLECT said:


> If there a .05% difference that is measured... Does that overshadow the environment? Will that difference be audible in a double blind test?


Why "Double Blind" Testing Can't Work For Audio - Audiophile Review


----------



## DeltaB

DC/Hertz said:


> But what about the BS you are selling?


Your assertion is like the guy, totally blind from birth, who stands in the shade of a rock cleft, screaming at the top of his lungs the assertion, "THE SUN NEVER SHINES!" Now, having awakened for over half a century, daily seeing the sun go from the east to west, stood in its rays and basked in it's warmth, ask yourself, how much validity would you place in the blind man's assertions. Doesn't make a whole lot of sense, does it.

You have a great day.


----------



## sqnut

DC/Hertz said:


> It appears you don't have any way to eliminate the car so that's what you are hearing.


You're right, in a car 90% of what we hear are early reflections, unlike a room where you're getting 20% direct sound, 40% early reflections and 40% late reflections. Before you jump and ask for citation, this is based on a study done by Harmon.

In a car combing starts kicking in around 1khz, based on wavelengths, proximity to reflective surfaces. But you start to hear its effects from about 600 hz up. The net effect of these early reflections is that we perceive the incident sound louder, hence an equalization issue. The other problem in a car is speakers at different distance, which is a TA issue. 

By using a dsp you can get a car sounding, staging and imaging like a good 2ch at home. The only difference is the size of stage.


----------



## Salami

I don't know dafuck you all are arguing about. It either sounds good to you AND works for your particular install or it don't. 

I just switched from some really high end A/B amps to class D to save space and allow me to use a preferred mounting location and from my fawked ears I swear it actually seems to sound just as good, maybe even a bit better. 

My only complaint is a have a slight turn off pop I did not have before.


----------



## ChrisB

Salami said:


> I don't know dafuck you all are arguing about. It either sounds good to you AND works for your particular install or it don't.
> 
> I just switched from some really high end A/B amps to class D to save space and allow me to use a preferred mounting location and from my fawked ears I swear it actually seems to sound just as good, maybe even a bit better.
> 
> My only complaint is a have a slight turn off pop I did not have before.


Did you switch to Alpine?


----------



## DPGstereo

Finally some thought proven discussion. I new you guys were out there. Thank you.


----------



## DC/Hertz

Where is the data that proves there are audible differences? Yeah there isn't any. 
Where is the data at proves they sound the same? Yeah that does exist. 

Look bud, using fancy words to describe something simple don't work around here. 
I'm very glad I can't hear differnces, it makes amp shopping easy. 
Hell speakers color way more then amps and the environment colors way more then speakers. 
The ones that think amps matter always seem to put the amps 1st. It should be 3rd or higher.


----------



## DPGstereo

DC/Hertz said:


> Where is the data that proves there are audible differences? Yeah there isn't any.
> Where is the data at proves they sound the same? Yeah that does exist.
> 
> Look bud, using fancy words to describe something simple don't work around here.
> I'm very glad I can't hear differnces, it makes amp shopping easy.
> Hell speakers color way more then amps and the environment colors way more then speakers.
> The ones that think amps matter always seem to put the amps 1st. It should be 3rd or higher.




In my experience, _speaker_ choice quickly can make a huge difference, agree.

_Tune_ is obviously huge. Hi-quality _head unit_ or _source_ absolutely matters. 
Starting with a good _recording/source-material_, a complete vehicle prep and install, quality _speakers_, SQ _source_, correctly setup _DSP_......after all of that done correctly....*amplifier choice does matter.*

Call Mosconi or any brand of amplifier you revere. Choose a company that offers both technologies. Not a company that pushes one design over another (not JL Audio, however I recently purchased a HD600/4 & HD1200/1). 
Ask, then really listen what that manufacture says about, "if you want best possible sound" no size or price limitation. Just ask, what is your best sounding full-range amplifier? Guess I better include, to be selective of who you start the conversation with.

I have found that when building/designing/installing a sound system, when goal is *optimum sound quality*, everything matters...most certainly amplifier choice. 
Only "snake oil" I've encountered on my quest for audio bliss, had been about inner-connect cables and speaker wire. I have a hard time believing you should spend 30% of total budget on cables & speaker. Have heard that from more than one "hi-end" home audio salesmen.





.


----------



## DC/Hertz

That company will tell me they would pick their most expensive amp. Because why make something expensive if they can't sell it? 
Btw, JL still has a few A/B.


----------



## drop1

DC/Hertz said:


> That company will tell me they would pick their most expensive amp. Because why make something expensive if they can't sell it?
> Btw, JL still has a few A/B.


Jl only has 1 a/b amp. The 300/4.
Im pretty sure the only reason they still have it is because of this very debate and the slash series still sells after all these years. They need an amp to match the slash class d mono amps. I feel like its their way of maintaining something for everyone.


----------



## Holmz

DeltaB said:


> Why "Double Blind" Testing Can't Work For Audio - Audiophile Review


You pretty much have been saying that audio is more like religion than science.
That makes sense with the magical that you have been preaching here.


----------



## DC/Hertz

drop1 said:


> Jl only has 1 a/b amp. The 300/4.
> Im pretty sure the only reason they still have it is because of this very debate and the slash series still sells after all these years. They need an amp to match the slash class d mono amps. I feel like its their way of maintaining something for everyone.


I once thought my old 450/4v2 was magic. Until I bit the class D bullet. 
Then I learned A/B is a dinosaur. It was 3x the size, 1/2 as efficient and 25% less power then I have now. And it retailed the same.


----------



## DeltaB

Holmz said:


> You pretty much have been saying that audio is more like religion than science.
> That makes sense with the magical that you have been preaching here.


Please go troll someone else.


----------



## Holmz

DeltaB said:


> Please go troll someone else.


That is a bit precious...
You come on a forum called DIY... And proclaim magic without providing any reason or evidence, and tell forum members to study up.

So far you have not explained how any of this "passive path gear" manifests itself in measurable difference, and then say that it cannot be measured.

Repeatable measurements are what we use differentiate magical non-sense concepts from scientific reality.

The questions being asked were an attempt to determine if there is any measurable differences in what you are proclaiming.

The burden of proof is on you. Save the hand waving and magical rainbows-n-unicorns non-sense.


----------



## DPGstereo

DC/Hertz said:


> I once thought my old 450/4v2 was magic. Until I bit the class D bullet.
> Then I learned A/B is a dinosaur. It was 3x the size, 1/2 as efficient and 25% less power then I have now. And it retailed the same.




The 450/4v2 is/was a nice amp. But no where near the Holy Grain of A/B technology. If this is your only reference...I get why you have the opinion you have. No offense intended.





.


----------



## DC/Hertz

DPGstereo said:


> The 450/4v2 is/was a nice amp. But no where near the Holy Grain of A/B technology. If this is your only reference...I get why you have the opinion you have. No offense intended.
> 
> 
> 
> 
> 
> .


Lol that was the last A/B I had. Not the only one. I've had A/B for 20 years. Class D for the last 5. 
Those Slash A/Bs held their own in the lanes. 
There is no holy grail. It's whatever fits your install. Now there are junk amps no doubt but that falls to build quality.


----------



## DeltaB

Holmz said:


> That is a bit precious...
> You come on a forum called DIY... And proclaim magic without providing any reason or evidence, and tell forum members to study up.
> 
> So far you have not explained how any of this "passive path gear" manifests itself in measurable difference, and then say that it cannot be measured.
> 
> Repeatable measurements are what we use differentiate magical non-sense concepts from scientific reality.
> 
> The questions being asked were an attempt to determine if there is any measurable differences in what you are proclaiming.
> 
> The burden of proof is on you. Save the hand waving and magical rainbows-n-unicorns non-sense.


I've offered no magic. I guess if you don't understand, then for you, it would be magic. Please go troll someone else. Have a great day!


----------



## DC/Hertz

DeltaB said:


> I've offered no magic. I guess if you don't understand, then for you, it would be magic. Please go troll someone else. Have a great day!


Brother you haven't provided anything. Just fluff words. If anyone is trolling it's you.


----------



## DeltaB

DC/Hertz said:


> Brother you haven't provided anything. Just fluff words. If anyone is trolling it's you.


With your youth comes the arrogance of thinking that you know it all. As nothing more than an end user, with no engineering background, and no experience in the audio field as a professional, and with blatant statements that "all amps sound the same, because you know better" doesn't do a lot at bolstering your expertise in the field. However, after seeing your listening habits, it's no surprise your subjective view is what it is. See an audiologist, and lastly, I'm not your brother, you haven't earned that type of familiarity with me. Have a great day!


----------



## DC/Hertz

lol I'm almost 40. What youth would that be? 
You are nothing but words. 
Give us some data to back up your claims. But I'm guessing you can't.


----------



## DeltaB

DC/Hertz said:


> lol I'm almost 40. What youth would that be?
> You are nothing but words.
> Give us some data to back up your claims. But I'm guessing you can't.


I've got kids at your age. Go back and re-read what I said, but this time, read to learn, rather than reading to make comments.


----------



## DC/Hertz

Still no data. Figures.


----------



## sq2k1

I am starting to think this forum should be sponsored by Dodge Ram.....the perfect truck for people who constantly butt heads.....


----------



## Holmz

DeltaB said:


> I've offered no magic. I guess if you don't understand, then for you, it would be magic. Please go troll someone else. Have a great day!


Adults ask clarifying questions in order to understand where the other party is coming from and to understand their claims, assertions and reasoning.


----------



## DeltaB

Holmz said:


> Adults ask clarifying questions in order to understand where the other party is coming from and to understand their claims, assertions and reasoning.


Let's first start with your assertion that any amp rated at a given THD at a given frequency at a given power level will sound the same as any other amp with the same parameters, ergo, they sound the same. This isn't true. Why? Because amp A , and it's devices may in fact perform the same as amp B @ 1kHz, however amp A uses an op-amp that has ever increasing THD as frequency increases, until you get to above 10kHz, and find A is now is not even close to the THD it had at 1kHz. Amp B is flat across the audio spectrum. This is not only measurable, but audible.

Next comes phase, Amp A exhibits over 120 degrees of phase shift in the first three octaves of it's operation and amp B is phase stable across the spectrum. This will not add or detract from the given THD rating from the above rating, (in your example 0.005% @ 1kHz) however, it's measurable as well as one of the most obvious audible differences.

Next comes behavior of amp A, which has poor PSRR and CMRR and hisses with little or no signal, and amp B does not exhibit this issue due to higher quality/build, and while amp A and B still have the same THD at 1kHz, it's certainly audible. A and B do not sound the same.

Now comes dynamic range, but exhibit the same THD @ 1kHz, yet amp A suffers a lower dynamic range, and this too is clearly audible and measurable between the differences between the softest and loudest output between the two.

Or where amp A uses devices that has poor linearity, (recovery time of signal input) and while it can easily produce a single or even two tone test, however when given complex audio signals may overshoot the initial rise by 20% and take 1.5ms to recover, (1kHz is 1ms, 1500Hz is 600μs) and amp B exhibits much less overshoot, and recovers in 600ns. Amp A will not even be able to produce signals in the envelope of overshoot and recovery, while amp B looses much less detail and recovery time is 0.0006ms, considerably less than amp A. This is very audible, and certainly measurable. Yet, both have the same THD at 1kHz.

Now comes passive components, where amp A is low pass filtered at -6db per octave above 16~18kHz, and looses detail and level as you move towards the upper end of the spectrum, where amp B uses a -12db roll-off at 24kHz and does not lose detail by reason of being filtered, again, neither impact THD at it's rated level, however will sound totally different in the upper octaves. Or passive devices like capacitors which can change polar response, level and tone, but will not affect THD. Again, measurable and audible.

My point is, THD is not the end all to begin the assertion that if amp A and B have the same THD they sound the same. The assertion is simply false on its face. Your question comes from a myopic view and understanding of audio in general, and makes authoritative assertions which are simply false.

Ignorance on your part, does not constitute error on my part. Get yourself a spectrum analyzer and go test for yourself.


----------



## Onyx1136

DeltaB said:


> Why "Double Blind" Testing Can't Work For Audio - Audiophile Review


That article is complete and total ********. It's nothing more than "audiophile" propaganda, written for the purpose of lending credence to the myth that there's some non quantifiable factor in audio that keeps it in the realm of art rather than science. It's not religion, it's just audio reproduction. There is no voodoo or secret sauce in audio that can't be accurately measured by modern electronics or scientific equipment, including human hearing. Harmon has done decades of testing in the realm of audio reproduction and human auditory perception, published stacks upon stacks of white papers on almost every conceivable factor related to it, yet those in the "audiophile" community continue to try to keep the industry in the dark ages by eschewing science in favor of dogmatic "audiophile" magic.


----------



## DeltaB

Onyx1136 said:


> That article is complete and total ********. It's nothing more than "audiophile" propaganda, written for the purpose of lending credence to the myth that there's some non quantifiable factor in audio that keeps it in the realm of art rather than science. It's not religion, it's just audio reproduction. There is no voodoo or secret sauce in audio that can't be accurately measured by modern electronics or scientific equipment, including human hearing. Harmon has done decades of testing in the realm of audio reproduction and human auditory perception, published stacks upon stacks of white papers on almost every conceivable factor related to it, yet those in the "audiophile" community continue to try to keep the industry in the dark ages by eschewing science in favor of dogmatic "audiophile" magic.


The purpose of the article is that it simply states, empirical data can not be derived by "double blind" tests. It is wholly subjective to the listeners perception. Also what is not said is that in an A/B "double blind" test, they have already utilized equalization on one to match the other. Its a stacked deck to begin with.

"Unlike a whole lot of other hobbies and pastimes, audio is either plagued by or -- if you like that sort of thing - blessed with constant dispute. In baseball, although the umpire can be wrong about some things, you can always tell for certain if the batter actually hits the ball and if the fielder actually catches it. Those are indisputable, as is the measured speed and quarter-mile-elapsed-time of a dragster. And, in the case of a "photo finish", whether of cars or horses or anything else, you can accurately record and measure the results and you can ALWAYS rely on what the measurements say. The same is true for photography, another favorite hobby of many audiophiles; where nobody would ever even consider arguing that different lenses, different film, or a different pixel count (for digital photography) don't make a difference, but in audio, argument about the basics has been going on ever since the hobby started, and there's no sign that it's ever going to stop. The reason for this ISN'T that Hi-Fi Crazies are inherently irrational or that their perceptive senses are either flawed or easily fooled; it's that, unlike all of those other fields, disciplines, or pastimes, in audio it's almost impossible to isolate any one single criterion to test, and even if that could be done, it would still be almost impossible to get any two or more people to opine on only just that one thing, and even if that COULD happen, the odds are that their opinions would have little value."


----------



## Onyx1136

DeltaB said:


> The purpose of the article is that it simply states, empirical data can not be derived by "double blind" tests. It is wholly subjective to the listeners perception. Also what is not said is that in an A/B "double blind" test, they have already utilized equalization on one to match the other. Its a stacked deck to begin with.


No, the purpose of the article is to attempt to invalidate scientific testing for the purpose of the magazine continuing to sell audio voodoo and wizardry to idiots that don't have even a high school understanding of how the scientific testing works. 

The article uses a ridiculous situation where the double blind portion of the A/B testing must be done in one large group, and asserts that because of the difficulties inherent in this situation that double blind testing doesn't work. This is a fallacy. First of all, double blind A/B testing can, and absolutely positively SHOULD be done on an individual basis. One test subject at a time, using the same testing apparatus. To put the whole testing group in a room and try to draw any meaningful conclusion would render all the testing data completely invalid for all the reasons listed in the "article." 

So the solution to the authors idiotic supposition, is to conduct testing process ONE PERSON AT A TIME. Problem solved, relevant data gathered, articles purpose invalidated, double blind testing process proven to work yet again. 

Furthermore, any conclusions drawn from that article are essentially invalid, as the entire premise was based on a proposed testing situation which would never have been used by any reasonable researcher.


----------



## DeltaB

Onyx1136 said:


> No, the purpose of the article is to attempt to invalidate scientific testing for the purpose of the magazine continuing to sell audio voodoo and wizardry to idiots that don't have even a high school understanding of how the scientific testing works.
> 
> The article uses a ridiculous situation where the double blind portion of the A/B testing must be done in one large group, and asserts that because of the difficulties inherent in this situation that double blind testing doesn't work. This is a fallacy. First of all, double blind A/B testing can, and absolutely positively SHOULD be done on an individual basis. One test subject at a time, using the same testing apparatus. To put the whole testing group in a room and try to draw any meaningful conclusion would render all the testing data completely invalid for all the reasons listed in the "article."
> 
> So the solution to the authors idiotic supposition, is to conduct testing process ONE PERSON AT A TIME. Problem solved, relevant data gathered, articles purpose invalidated, double blind testing process proven to work yet again.
> 
> Furthermore, any conclusions drawn from that article are essentially invalid, as the entire premise was based on a proposed testing situation which would never have been used by any reasonable researcher.


Sadly, your assertion is just as subjective as the results of the subjective view of the listener. Distortion analyzers, spectrum analyzers and oscilloscopes are not subject to your or my subjective viewpoint.

Subjective: adjective;
1) based on or influenced by personal feelings, tastes, or opinions.


----------



## Holmz

DeltaB said:


> Sadly, your assertion is just as subjective as the results of the subjective view of the listener. Distortion analyzers, spectrum analyzers and oscilloscopes are not subject to your or my subjective viewpoint.
> 
> Subjective: adjective;
> 1) based on or influenced by personal feelings, tastes, or opinions.


Maybe we are getting somewhere finally.

My assertion was that if two amplifiers (pick your metric) have measured "perfection" then they cannot sound different. I suppose that would need to include damping factor for a complex load.

And for two amplifiers to sound different, then the output signals must be different. 

Basically one could correlate that two different signal sound different, and that should be repeatable.

It still does not answer what the mechanisms are that make them different.


----------



## DeltaB

Holmz said:


> Maybe we are getting somewhere finally.
> 
> My assertion was that if two amplifiers (pick your metric) have measured "perfection" then they cannot sound different. I suppose that would need to include damping factor for a complex load.
> 
> And for two amplifiers to sound different, then the output signals must be different.
> 
> Basically one could correlate that two different signal sound different, and that should be repeatable.
> 
> It still does not answer what the mechanisms are that make them different.


No, you asked "How does one amp with 0.005% THD differ in "soundstage, tonality, coming aliveness, more accuracy"... from another amp with the same 0.005% THD?" and "Therefore I am failing to see how two amplifiers with 0.005% THD+N would be able to sound much different through the same speakers"

Since you don't seem to able to remember what you are asking, let's move to the assertion of your "perfect" amplifier made from rare earth "unobtainium ether", and selling "the hand waving and magical rainbows-n-unicorns non-sense"... Please spare me. Move on.


----------



## Holmz

DeltaB said:


> No, you asked "How does one amp with 0.005% THD differ in "soundstage, tonality, coming aliveness, more accuracy"... from another amp with the same 0.005% THD?" and "Therefore I am failing to see how two amplifiers with 0.005% THD+N would be able to sound much different through the same speakers"
> 
> Since you don't seem to able to remember what you are asking, let's move to the assertion of your "perfect" amplifier made from rare earth "unobtainium ether", and selling "the hand waving and magical rainbows-n-unicorns non-sense"... Please spare me. Move on.


Correct - I picked a number pretty close to zero. There are not many amps in that level of goodness.
You will note that is a question, which needed in a question mark, and is therefore not an assertion.
The "failing to see" is also not an assertion.

The other point, if you recall, was that a speaker's distortion can often be greater than the level of distortion of an amplifier at 0.005%.
Which begged the question of how can one hear the amplifier's influence if the speaker's negative influence is 10x higher?

Please note that this last 1/2 of the concept is a question, and not an assertion.
The only assertion was that a speaker's distortion can be higher than the 0.005% of a special amplifier.


----------



## DC/Hertz

The absolute only way is a blind test. That's proven. 
So much proof against your claim. 
And you expect us to stop trusting our ears and just believe you.


----------



## DeltaB

DC/Hertz said:


> The absolute only way is a blind test. That's proven.
> So much proof against your claim.
> And you expect us to stop trusting our ears and just believe you.


Objective data is quantitative, and that does not change with the observer. Subjective data is qualitative, and changes with the observer. Sell your supposition to someone who doesn't know the difference. Like I said in an earlier post, I've seen your listening habits. Find an audiologist and move on.


----------



## DeltaB

Holmz said:


> Correct - I picked a number pretty close to zero. There are not many amps in that level of goodness.
> You will note that is a question, which needed in a question mark, and is therefore not an assertion.
> The "failing to see" is also not an assertion.
> 
> The other point, if you recall, was that a speaker's distortion can often be greater than the level of distortion of an amplifier at 0.005%.
> Which begged the question of how can one hear the amplifier's influence if the speaker's negative influence is 10x higher?
> 
> Please note that this last 1/2 of the concept is a question, and not an assertion.
> The only assertion was that a speaker's distortion can be higher than the 0.005% of a special amplifier.


My 1978 Pioneer Spec-4 is 0.005% THD, and I don't care if you use paper cone or hybrid ionized plasma tweeters. Your assertion is just more of the same. BS. Obviously I'd like to leave you a way to save face so it might be better to just move on...


----------



## DC/Hertz

So what are my listening habits since you know me so well? 
This morning it was Abbey road!


----------



## mrichard89

Speaking of high-power class D amps, has anyone here used Soundigital amps in an SQ focused install?


----------



## DC/Hertz

mrichard89 said:


> Speaking of high-power class D amps, has anyone here used Soundigital amps in an SQ focused install?


I would use the new EVO if the full range and monos where even close to the same measurements.


----------



## Ziggyrama

Here's what I see:

- a test on a bench that can set up to feed a consistent test signal into an amplifier. This can be done in a very controller environment such that each amp does not the exact same input source signal.

- the output signal can be measured with very accurately, with very high sampling rate. Once that is done, one can analyze for distortion and phase shifting. I imagine a great to show the data distribution would be to plot distortion and phase shift against frequency and show the trends. That would demonstrate behavior of an amp with respect to frequency and put an end to arm waving and speculation.

Once you do this, everything else is caused by other external factors. This seems pretty straightforward and I believe this would not take absurdly expensive equipment to stage. The problem is, I don't have the gear to do it and I am willing to bet 99.99% of people here don't have means or the know-how to set this up. I am sure someone will still claim they have dog ears and can hear things that science definitively proves you cannot but we always get those folks in every group.

What am I missing? IMO, we're at a point that arguing more about this isn't going to solve anything. Unless someone is willing to put the amp on a bench and do a true test, document all the data and show what it does, with no bias, someone will poke holes in it and ague their ears are saying something else. FWIW.


----------



## sqnut

Ziggyrama said:


> What am I missing?.........


The simple fact that at the end of the chain, not all the ears that are hearing are also listening. Given this, it is possible that the ears that are listening would have a higher degree of correlation but this would get lost in the more dispersed results from those hearing. Now when you look at the overall result it's diffused and inconclusive.

deadspin-quote-carrot-aligned-w-bgr-2<\/title><path d="M10,3.5l3-3,3,3Z" style="fill:%23fff;stroke:%23fff"/><path d="M0,3.5H10l3-3,3,3H26" style="fill:none;stroke:%231b3a4d"/><\/svg>')}.f_branding_on.blog-group-deadspin .editor-inner.post-content .pu

Those who compete in the lanes will know, that there are folks who can sit in any average car, and get it sounding much better in 15 mts. You can't be a good tuner without being a good listener. I'm all for science, but there is a huge difference between hearing and listening.


----------



## Ziggyrama

sqnut said:


> The simple fact that at the end of the chain, not all the ears that are hearing are also listening. Given this, it is possible that the ears that are listening would have a higher degree of correlation but this would get lost in the more dispersed results from those hearing. Now when you look at the overall result it's diffused and inconclusive.
> 
> deadspin-quote-carrot-aligned-w-bgr-2<\/title><path d="M10,3.5l3-3,3,3Z" style="fill:%23fff;stroke:%23fff"/><path d="M0,3.5H10l3-3,3,3H26" style="fill:none;stroke:%231b3a4d"/><\/svg>')}.f_branding_on.blog-group-deadspin .editor-inner.post-content .pu
> 
> Those who compete in the lanes will know, that there are folks who can sit in any average car, and get it sounding much better in 15 mts. You can't be a good tuner without being a good listener. I'm all for science, but there is a huge difference between hearing and listening.


Yes, I have instinctively figured out that listening is a skill that needs to be honed and practiced, mainly based on my own discovery over the last 18 months. After getting into this hobby, I found that my ability to identify tones and spot tonal problems has increased over time as I have spent time critically listening to my tune and work on making it better. As a result, I find myself enjoying music more now and I I am hearing things in it that I did not before.

There is research and studies that show that subjects that are trained to listen to tones make fore better study participants since they provide much more consistent feedback. Harman even put out a piece of software to help us with training. I haven't gone through it yet but it looks very appealing. Boot camp for your ears:

Harman How to Listen


----------



## sqnut

Ziggyrama said:


> Boot camp for your ears:
> 
> Harman How to Listen


That's what I trained with. Took me about 18 months to be able to to pick a 0.25db cut/boost at 1/3 oct level, 7 times out of 10. The other times I was +/- 1/3 oct from the actual frequency. I've referenced that Harmon Tool in many tuning threads. Highly recommended if you're serious about tuning.


----------



## Hillbilly SQ

sq2k1 said:


> I am starting to think this forum should be sponsored by Dodge Ram.....the perfect truck for people who constantly butt heads.....


"Ram" has been their own brand for 7 or 8 years nowFiat Ram is more correct.


----------



## ChrisB

mrichard89 said:


> Speaking of high-power class D amps, has anyone here used Soundigital amps in an SQ focused install?


I'm still waiting on them to come out with a staggered, multi-channel, GaN amplifier...


----------



## DeltaB

ChrisB said:


> I'm still waiting on them to come out with a staggered, multi-channel, GaN amplifier...


It won't be many years in the future, before we start seeing GaN FET emerging. And while GaN has been used in another arena, (RF spectrum) for a bit, it has been slow to hit the automotive market. One great reason for this, is that only about 5 major manufacturers are currently providing GaN, and the cost of MOSFET so low, and the price difference today, it has been the mark of the automotive amp field to stick to 30 year old design and low-low cost.

Having said that, with currently available devices, we have the ability to start producing Class D with amazing results that can rival any other class, including pure Class A.


----------



## swoardrider

DC/Hertz said:


> I once thought my old 450/4v2 was magic. Until I bit the class Dullet.
> Then I learned A/B is a dinosaur. It was 3x the size, 1/2 as efficient and 25% less power then I have now. And it retailed the same.


That's what I thought. Started off on a late '80's class A/B old school PPI amp, back when they were the sh*t. Personally owned or worked with the JL Slash, Zapco DC Reference, Arc KAR, XDI, etc over the years.

Recently ran the Alpine PDX-V9 for a year and couldn't take it anymore. Switched it out to the Mosconi A/S 100.4, moved the PDX-9 over to rear fill and subwoofer duty, and loving every minute of it. Sooooooo glad to get my Class A/B back for front stage. PDX, XDI, and unfortunately the mediocre Slash 300/4 all lacked impact and imaging for my ears. PDX and XDI put out plenty of power, but seem to lack "soul" if that makes any sense. Kinda like the music was compressed (think MP3 vs Lossless). The Slash I think just didn't put out enough power.

I'm currently building another system for my girlfriend's car, which will consist of 2 Class G/H ARC KARs and a class D for the sub. My girl likes the sound of an SQL system, and the KARs seem to have the best sound vs size vs power for the power hungry components that I'm using. And the class D fanless sub amp can be buried behind a trim panel without the need for much airflow.

My point is that each class of amp has it's place in audio systems. But if we are talking about full range SQ sound, (with no size or efficiency limit), anyone that thinks a clean, unmolested 2 channel stereo signal going thru a Class D amp sounds the same as a Class A, or A/B with same measured power is smoking crack. There's a reason why 6 figure home audio mono block amps are Class A or A/B. They simply produce the best full range sound per watt.


----------



## audiocholic

what do you guys think of the Mosconi D2 100.4 dsp?


is it worthwile? will it power my Pioneer stage 4 c172prs's.


----------



## DeltaB

swoardrider said:


> That's what I thought. Started off on a late '80's class A/B old school PPI amp, back when they were the sh*t. Personally owned or worked with the JL Slash, Zapco DC Reference, Arc KAR, XDI, etc over the years.
> 
> Recently ran the Alpine PDX-V9 for a year and couldn't take it anymore. Switched it out to the Mosconi A/S 100.4, moved the PDX-9 over to rear fill and subwoofer duty, and loving every minute of it. Sooooooo glad to get my Class A/B back for front stage. PDX, XDI, and unfortunately the mediocre Slash 300/4 all lacked impact and imaging for my ears. PDX and XDI put out plenty of power, but seem to lack "soul" if that makes any sense. Kinda like the music was compressed (think MP3 vs Lossless). The Slash I think just didn't put out enough power.
> 
> I'm currently building another system for my girlfriend's car, which will consist of 2 Class G/H ARC KARs and a class D for the sub. My girl likes the sound of an SQL system, and the KARs seem to have the best sound vs size vs power for the power hungry components that I'm using. And the class D fanless sub amp can be buried behind a trim panel without the need for much airflow.
> 
> My point is that each class of amp has it's place in audio systems. But if we are talking about full range SQ sound, (with no size or efficiency limit), anyone that thinks a clean, unmolested 2 channel stereo signal going thru a Class D amp sounds the same as a Class A, or A/B with same measured power is smoking crack. There's a reason why 6 figure home audio mono block amps are Class A or A/B. They simply produce the best full range sound per watt.


You can try to dis Class D for SQ, however the market and designs are making Class D performance equal to even Class A performance.

Stereo Power Amplifier SE-R1 | Reference Class R1 Series | Technics US


----------



## swoardrider

DeltaB said:


> You can try to dis Class D for SQ, however the market and designs are making Class D performance equal to even Class A performance.
> 
> Stereo Power Amplifier SE-R1 | Reference Class R1 Series | Technics US


You can post all the articles you want, but you're not going to convince my ears in my own car. Since switching amps, the imaging is wider, has more depth, and I can hear musical notes that weren't there before. Conclusion, it sounds 10 times better with my Mosconi amp then my class D Alpine. 
A cheap A/B amp may not sound as good as a quality class D. But I personally have not found a quality class D that sounds as good as a quality class A/B


----------



## swoardrider

DeltaB said:


> You can try to dis Class D for SQ, however the market and designs are making Class D performance equal to even Class A performance.
> 
> Stereo Power Amplifier SE-R1 | Reference Class R1 Series | Technics US


I'll believe it when I hear it by running that Technics amp against a pair of mono block JC1 Parasound's. I'm sure it sounds good, but the Parasounds are just pure buttery smoooooth!


----------



## DeltaB

swoardrider said:


> You can post all the articles you want, but you're not going to convince my ears in my own car. Since switching amps, the imaging is wider, has more depth, and I can hear musical notes that weren't there before. Conclusion, it sounds 10 times better with my Mosconi amp then my class D Alpine.
> A cheap A/B amp may not sound as good as a quality class D. But I personally have not found a quality class D that sounds as good as a quality class A/B


Crack isn't required, however, being informed does. The greatest hurdle has been in Class D the output devices themselves, as MOSFET does not lend itself to providing the performance required. GaN-FET does. Is the automotive market slow to respond to industry changes? Yes. Much of the automotive market is still utilizing antiquated devices and designs left over from the late 70's and early 80's. So before you start making blanket statements concerning some specific Class, you might want to actually want to stay informed, rather than sitting there making proclamations that may have been valid a decade ago, but certainly not today. Just because you haven't been exposed to quality Class D designs, doesn't mean they don't exist, it just shows your own lacking of being informed and exposure to trends in the market. Go educate yourself. As for me, I don't need crack, I have already heard some very fine quality Class D.

Can Class-D Amplifier Audio Performance Get Any Better? | Electronic Design

Why We'll Soon Be Living In A Class D World - Audiophile Review


----------



## Alleycat

I have not made a switch to class D amps yet because of my love for the old school ppi amps .just not sure on the reliability over time of these amps.also what about the taramps high voltage amps are those class D amps.


----------



## sqnut

swoardrider said:


> You can post all the articles you want, but you're not going to convince my ears in my own car. Since switching amps, the imaging is wider, has more depth, and I can hear musical notes that weren't there before. Conclusion, it sounds 10 times better with my Mosconi amp then my class D Alpine


An amp can't widen your sound stage, just like it can't make your stage deeper and it's sure as hell not going to make you magically hear musical notes that weren't there before. Your subjective and psychoacoustic experiences are just that. Read up on what an amp does and how it works.


----------



## DeltaB

Alleycat said:


> I have not made a switch to class D amps yet because of my love for the old school ppi amps .just not sure on the reliability over time of these amps.also what about the taramps high voltage amps are those class D amps.


LOL! Yes, taraamps are Class D. My question is in respect to these amps, why use an amp that meets the needs of listening levels that doesn't cause hearing loss, when you can use a 2 ton wrecking ball.


----------



## DeltaB

swoardrider said:


> I'll believe it when I hear it by running that Technics amp against a pair of mono block JC1 Parasound's. I'm sure it sounds good, but the Parasounds are just pure buttery smoooooth!


It mazes me on this site the number of times that I have seen someone who has absolutely zero exposure to a given item of discussion, making assertions out of ignorance (not knowing) and attempting to sell it as knowledge. (to know)

The JC1 has a rated THD <0.15% at full power. The Class D Technics is THD+N 0.05% at full rated power. My 1978 Pioneer SPEC 4 is rated at 0.005% at full rated power, and is a dual mono-block design in one chassis. There are many fine amps out there.


----------



## Hillbilly SQ

Like religion and politics this thread will probably never have all parties in full agreement. It's just like people who swap gear constantly trying to fix what the car audio environment messes up while scoffing at people who use dsp's. A wise enthusiast will choose the right tools for THEIR system goals. If someone wants to pull a ton of current and take up a lot of room with a/b amps that's on them. The rest of us will enjoy our music with current sipping class d amps and not worry about whether or not our car will start if we decide to rock out for half an hour with the engine off


----------



## DeltaB

Hillbilly SQ said:


> Like religion and politics this thread will probably never have all parties in full agreement. It's just like people who swap gear constantly trying to fix what the car audio environment messes up while scoffing at people who use dsp's. A wise enthusiast will choose the right tools for THEIR system goals. If someone wants to pull a ton of current and take up a lot of room with a/b amps that's on them. The rest of us will enjoy our music with current sipping class d amps and not worry about whether or not our car will start if we decide to rock out for half an hour with the engine off


Agreed on many levels. Major manufacturers out there are aware of the advantages that GaN-FET provides, and there are designs in the pipeline, I just hope in the next few years we see these newer designs hit the market in the automotive field.


----------



## Aaron Clinton

*DioGuardo is working on one right now.*


----------



## Babs

Yeah that was the thing I noticed about that Technics amp. GaN.. It’s apparently on another level compared to most usual class-D’s out there.. If SounDigital or someone can get those things to market and they become more affordable, they might change some minds. 


Sent from my iPhone using Tapatalk Pro


----------



## DeltaB

Babs said:


> Yeah that was the thing I noticed about that Technics amp. GaN.. It’s apparently on another level compared to most usual class-D’s out there.. If SounDigital or someone can get those things to market and they become more affordable, they might change some minds.
> 
> 
> Sent from my iPhone using Tapatalk Pro


NXP is one of the largest suppliers. They are about 5 major vendors out there.


----------



## DeltaB

Aaron Clinton said:


> *DioGuardo is working on one right now.*


Saddle an ESS Sabre with an OPA-1612 fed into GaN-FET and you are on your way to a Class A killer.

In fact, the NVX JAD I have, if I used something like the Transphorm TO-247 and TO-220 cased GaN-FETs, leave the Infineon gate driver, just change the 2 resistors to drop dead time from 25ns down to 10ns and leave the frequency at 400kHz, and leverage these advantages.


----------



## GEM592

I'm a fan of your posts, Delta. Thanks for your input.


----------



## swoardrider

DeltaB said:


> It mazes me on this site the number of times that I have seen someone who has absolutely zero exposure to a given item of discussion, making assertions out of ignorance (not knowing) and attempting to sell it as knowledge. (to know)
> 
> The JC1 has a rated THD <0.15% at full power. The Class D Technics is THD+N 0.05% at full rated power. My 1978 Pioneer SPEC 4 is rated at 0.005% at full rated power, and is a dual mono-block design in one chassis. There are many fine amps out there.


And a Goldmund Telos 5000 weighs 691lbs and has a THD of 0.0005%. So what's your point exactly?? 
I can quote numbers with you all day long, and I can google amazing advancements in tech like GaN-FET. But until it's ready available in a mass produced 12v amp, it's useless to this thread. Class D may very well be the thing of the future, but so is affordable space travel!!! Until you prove to me with my own ears that Class D will "send me to the moon and back with audible bliss" Class A and A/B is a ready and viable technology, that last time I checked, every single high-end car audio brand in the world uses. That is an undisputed fact. You spat off numbers in this thread that very well may be accurate, but are useless to this discussion. Go convince Sinfoni, Mosconi, Arc, Zapco, Linear Power, and 10 other boutique competition winning companies that they are doing it wrong, and I'll look like the world's biggest idiot and you will be the next Richard Branson


----------



## GEM592

swoardrider said:


> And a Goldmund Telos 5000 weighs 691lbs and has a THD of 0.0005%. So what's your point exactly??
> I can quote numbers with you all day long, and I can google amazing advancements in tech like GaN-FET. But until it's ready available in a mass produced 12v amp, it's useless to this thread. Class D may very well be the thing of the future, but so is affordable space travel!!! Until you prove to me with my own ears that Class D will "send me to the moon and back with audible bliss" Class A and A/B is a ready and viable technology, that last time I checked, every single high-end car audio brand in the world uses. That is an undisputed fact. You spat off numbers in this thread that very well may be accurate, but are useless to this discussion. Go convince Sinfoni, Mosconi, Arc, Zapco, Linear Power, and 10 other boutique competition winning companies that they are doing it wrong, and I'll look like the world's biggest idiot and you will be the next Richard Branson


The thing is, this is a "class D compensation" thread. So it's really best to just flatter them.


----------



## PPI_GUY

DeltaB said:


> Saddle an ESS Sabre with an OPA-1612 fed into GaN-FET and you are on your way to a Class A killer.
> 
> In fact, the NVX JAD I have, if I used something like the Transphorm TO-247 and TO-220 cased GaN-FETs, leave the Infineon gate driver, just change the 2 resistors to drop dead time from 25ns down to 10ns and leave the frequency at 400kHz, and leverage these advantages.


I'm pretty excited to see/hear the first iterations of GaN-FETs in car audio...whenever that happens. Lots of promise there. 
So, the NVX amps use a 400kHz switching frequency? Thanks for mentioning that, I had wondered for some time. Interesting.


----------



## DeltaB

swoardrider said:


> And a Goldmund Telos 5000 weighs 691lbs and has a THD of 0.0005%. So what's your point exactly??
> I can quote numbers with you all day long, and I can google amazing advancements in tech like GaN-FET. But until it's ready available in a mass produced 12v amp, it's useless to this thread. Class D may very well be the thing of the future, but so is affordable space travel!!! Until you prove to me with my own ears that Class D will "send me to the moon and back with audible bliss" Class A and A/B is a ready and viable technology, that last time I checked, every single high-end car audio brand in the world uses. That is an undisputed fact. You spat off numbers in this thread that very well may be accurate, but are useless to this discussion. Go convince Sinfoni, Mosconi, Arc, Zapco, Linear Power, and 10 other boutique competition winning companies that they are doing it wrong, and I'll look like the world's biggest idiot and you will be the next Richard Branson


Do you actually hear yourself? I gave you information on a Class D amp from Panasonic's Technics division out there on the market, and it is now your responsibility to either listen or not. I don't care. Pioneer's new high end home A/V lineup is Class D GaN-FET. 

You can place your hands over your eyes and proclaim, "well I just can't see that!" Remember, it was you who said, "But if we are talking about full range SQ sound, (with no size or efficiency limit), anyone that thinks a clean, unmolested 2 channel stereo signal going thru a Class D amp sounds the same as a Class A, or A/B with same measured power is smoking crack." I'm not interested in your arguments based on extremes of stupidity. Have a great day.

A/V Receivers | Pioneer Electronics USA


----------



## DC/Hertz

I’m going to direct swap my little Korean monster full range to the Zapco 4sq in a few months. When I hear them sounding the same and I’m satisfied with the 1/2 power of the Zapco I’ll sell the SS4 for a $100 profit. If I’m not satisfied with 1/2 the power I’ll toss the 4sq on here for sale. I’m not using all the power I have now so we will see. 
I’ve got pretty good ears but I doubt anyone here trust my newb opinion. 
And if the Zapco magically makes something better I’ll admit it.


----------



## audiocholic

I'am not stating anything but kindly want to share my experience yesterday with not 1 but 7 mosconi dealers accross 3 nations.



yes you read right I actually got in touch with the German,British and Turkish distributors and a few dealers of Gladen/Mosconi asking them there input on the D2 100.4 dsp vs the ONE 130.4 dsp and that I would power up Pioneer Stage 4 C172PRS's.



not almost but literally very single one of them stated the identical responses stating the following, keep in mind the D class D2 is more expensive then the ONE series.


1) both amps will power up my comps without trouble
2) unless size/room is an issue that the one series is a more detailed,natural sounding amp and without a question better than the D2.

3) asking them the reason behind this literally all stated the D2 was d class and digital and that the one series (especially the 130.4dsp vs the older 120.4dsp) is AB and has a better topology and sounds significantly better.




to be honest seeing that every single one of these dealers stated the one 130.4dsp being better and that the one is actually and older,lower line item and is cheaper (usually dealers promote more expensive line ups) I kind of have my doubts of this subject once again.


I even wrote to end users (us) whom have tried both series which were actually a very hard to find number of 3 guys in 5 sites  and all 3 stated no comparison definatley the AB one series.


----------



## ca90ss

audiocholic said:


> 3) asking them the reason behind this literally all stated the D2 was d class and digital and that the one series (especially the 130.4dsp vs the older 120.4dsp) is AB and has a better topology and sounds significantly better.


Class d isn't digital. If the dealers you talked to don't even know the basics I wouldn't put a lot of stock in anything they had to say.


----------



## audiocholic

ca90ss said:


> Class d isn't digital. If the dealers you talked to don't even know the basics I wouldn't put a lot of stock in anything they had to say.



the D2 has an edge over the one series as it has SP DIF digital input, the statement its digital was that its digital input capable vs the one isnt but that even though this advantage the one is far superior.


cant speak for any of these distributor or dealers knowledge but I find it hard to believe that all would be soo inline with there statements.


----------



## Jeffdachefz

swoardrider said:


> And a Goldmund Telos 5000 weighs 691lbs and has a THD of 0.0005%. So what's your point exactly??
> I can quote numbers with you all day long, and I can google amazing advancements in tech like GaN-FET. But until it's ready available in a mass produced 12v amp, it's useless to this thread. Class D may very well be the thing of the future, but so is affordable space travel!!! Until you prove to me with my own ears that Class D will "send me to the moon and back with audible bliss" Class A and A/B is a ready and viable technology, that last time I checked, every single high-end car audio brand in the world uses. That is an undisputed fact. You spat off numbers in this thread that very well may be accurate, but are useless to this discussion. Go convince Sinfoni, Mosconi, Arc, Zapco, Linear Power, and 10 other boutique competition winning companies that they are doing it wrong, and I'll look like the world's biggest idiot and you will be the next Richard Branson


No one needs to prove sh*t to you. lmfao. People stuck in the past like you can just live under a rock until they die and become fossils nobody even cars about.


----------



## swoardrider

Jeffdachefz said:


> No one needs to prove sh*t to you. lmfao. People stuck in the past like you can just live under a rock until they die and become fossils nobody even cars about.


I absolutely, positively, without a doubt love people like you and your 30,000 watts, that basically take the Greek Theatre's sound system and put it in your car, thinking that rattling the neighbors fine china is a "good sounding" system 
This is a Class D SQ thread, or (lack there of SQ). There's already morons in here quoting technology that's yet to be built for 12V. Dipshits in here quoting nonsense that have never picked up a musical instrument in there life. And now bass heads who think cheap flea market components sound as good as precision built transducers and amplifiers. Go over and troll the SPL forums


----------



## swoardrider

sqnut said:


> An amp can't widen your sound stage, just like it can't make your stage deeper and it's sure as hell not going to make you magically hear musical notes that weren't there before. Your subjective and psychoacoustic experiences are just that. Read up on what an amp does and how it works.


Oh really? Here's one screenshot of a professional amp review basically stating the opposite. This is by a person that's probably a lot more qualified than you are who says almost exactly what I'm hearing with my Mosconi A/B. And he's reviewing a Class G/H.
I could dig up reviews all day long about how different amps change the sound stage, depth, realism, imaging, etc but I know I'd be just waisting my time as you are already one of the many zombies that feel an amp is there to just boost power like it's a Wilson Antenna cell phone booster or something to that effect.


----------



## Holmz

swoardrider said:


> Oh really? Here's one screenshot of a professional amp review basically stating the opposite. This is by a person that's probably a lot more qualified than you are who says almost exactly what I'm hearing with my Mosconi A/B. And he's reviewing a Class G/H.
> I could dig up reviews all day long about how different amps change the sound stage, depth, realism, imaging, etc but I know I'd be just waisting my time as you are already one of the many zombies that feel an amp is there to just boost power like it's a Wilson Antenna cell phone booster or something to that effect.


Can THD+N and damping factor specs five any insight?

I see the power specs, but many of these appear to have no closed loop feedback. If one is driving a load that not purely resistive, then I am wondering how well they really work on a speaker.

I also see claims of golden ears, which I am not sure I have...
So I would assume that most amps approaching 0% THD+N and a high damping factor would sound o'roight.

Do you put credence in specs?


----------



## Ziggyrama

Holmz said:


> Can THD+N and damping factor specs five any insight?
> 
> I see the power specs, but many of these appear to have no closed loop feedback. If one is driving a load that not purely resistive, then I am wondering how well they really work on a speaker.
> 
> I also see claims of golden ears, which I am not sure I have...
> So I would assume that most amps approaching 0% THD+N and a high damping factor would sound o'roight.
> 
> Do you put credence in specs?


Interesting read on damping factor and specs. Warning, they use math to demonstrate what is really going on. Moral of the story, it depends on the overall configuration.

http://eaw.com/amplifier-damping-factor-more-is-better-or-is-it/

Sent from my Pixel using Tapatalk


----------



## Ziggyrama

swoardrider said:


> Oh really? Here's one screenshot of a professional amp review basically stating the opposite. This is by a person that's probably a lot more qualified than you are who says almost exactly what I'm hearing with my Mosconi A/B. And he's reviewing a Class G/H.
> I could dig up reviews all day long about how different amps change the sound stage, depth, realism, imaging, etc but I know I'd be just waisting my time as you are already one of the many zombies that feel an amp is there to just boost power like it's a Wilson Antenna cell phone booster or something to that effect.


A pretty good explanation of what what staging is and how sound characteristics shape your perception of it. Notice overwhelming majority of it is shaped by frequency response, TA and relative differences between channels which is largely defined by the room, the driver and overall tune:

https://www.acousticfields.com/sound-stage-height-width-depth/

One theory of mine is that different amplifiers have different latencies and possibly different variation between channel responses, due to their design which interacts with your specific room thus creating a unique sonic response which is what you hear. Clear as mud?

Lastly, take all "pro" reviews with a grain of salt. Just like any other profession, there are few really good people and lots of clowns and misinformed followers that just do what they do because that is how the person before then did it. I found this to be true all the way from engineering down to landscaping. Amazingly consistent.

Sent from my Pixel using Tapatalk


----------



## DeltaB

swoardrider said:


> I absolutely, positively, without a doubt love people like you and your 30,000 watts, that basically take the Greek Theatre's sound system and put it in your car, thinking that rattling the neighbors fine china is a "good sounding" system
> This is a Class D SQ thread, or (lack there of SQ). There's already morons in here quoting technology that's yet to be built for 12V. Dipshits in here quoting nonsense that have never picked up a musical instrument in there life. And now bass heads who think cheap flea market components sound as good as precision built transducers and amplifiers. Go over and troll the SPL forums


And then there are "pots" attempting to call others a "kettle"... (can you say psychological projection) You first assert positions concerning a Class of amplification, and when presented with information that clearly shows your position rather weak, you then change the argument to form factor, and when that doesn't work either, you assert that unless someone convinces manufacturers to adopt a given technology, everyone is wrong. Conversing with you is much like trying to nail Jello to a tree.

How do you know someone doesn't have a musical background? Or that someone doesn't have enough common sense to see that your staunch position is rather biased? Creating music is an art, reproducing it is a science.


----------



## sqnut

swoardrider said:


> Oh really? Here's one screenshot of a professional amp review basically stating the opposite. This is by a person that's probably a lot more qualified than you are who says almost exactly what I'm hearing with my Mosconi A/B. And he's reviewing a Class G/H.
> I could dig up reviews all day long about how different amps change the sound stage, depth, realism, imaging, etc but I know I'd be just waisting my time as you are already one of the many zombies that feel an amp is there to just boost power like it's a Wilson Antenna cell phone booster or something to that effect.


Seriously? You're substantiating your claim with 'paid for' reviews? :laugh:


----------



## Hillbilly SQ

Why did my JL XD800/8 "sound" so much better than my pair of Mosconi One 120.4's? The a/b Mosconi amps had more power so obviously got louder but the XD sounded like it had better control of the speakers. Was more detailed too. The little details got through better and overall a great amp. Too bad it had that board noise that some of the XD's are known for. My Arc XDI doesn't have that same "sound" and considering going with an RD 5ch and 4ch since they supposedly "sound" just like the XD series. And I used to play Percussion in school so I'm a big stickler for the impact instruments.


----------



## dcfis

Not so sure the rd will sound like the xd. Agree the xdi has a pleasing warm and slightly rounded sound


----------



## DC/Hertz

I wish I knew what all the audiophile terms sounded like. 
All I know is does it sound accurate or not. 
Which has little to nothing to do with the amplifier.


----------



## Holmz

Ziggyrama said:


> Interesting read on damping factor and specs. Warning, they use math to demonstrate what is really going on.
> ...


They use math, but math is a language of physics. (This is more like speaking in tongues. :mean: )

It does make some sense in terms of wires and wiring, but I was inferring in the sense of the output impedance of a class D amplifier, and specifically the open loop jobs which are more linear with the GAs parts. (More linear because the opening closing times are faster) how this is magical in a circuit that is running like a 1bit PWM D2A, and which is then filtered and choked to audio seems like something that could be accounted for as compensation in the PWM side?

Is it really open loop?
and how does that affect the amplifier's output impedance?


----------



## Holmz

DC/Hertz said:


> I wish I knew what all the audiophile terms sounded like.
> All I know is does it sound accurate or not.
> Which has little to nothing to do with the amplifier.


I believe that your point of environment has been noted. Does that mean that one totally ignores the amplifiers?

Can the sound treatment etc, be in another thread, or dos it overwhelm the discussion on amplifiers?


----------



## DeltaB

https://www.eeweb.com/blog/alex_lidow/how-to-gan-egan-fets-in-high-performance-class-d-audio-amplifiers


----------



## DC/Hertz

Holmz said:


> I believe that your point of environment has been noted. Does that mean that one totally ignores the amplifiers?
> 
> Can the sound treatment etc, be in another thread, or dos it overwhelm the discussion on amplifiers?


As long as it’s not a POS and makes enough power, I’m not picky. 
I once was but I was gullible.


----------



## DeLander

I'm pretty happy with the 4 different PPI amps that I've installed. 2 Phantoms in my truck and 2 Ion series in my daughter's car. 
I know they're not in the same class as some mentioned here, but they make good power on the cheap


----------



## PPI_GUY

DeLander said:


> I'm pretty happy with the 4 different PPI amps that I've installed. 2 Phantoms in my truck and 2 Ion series in my daughter's car.
> I know they're not in the same class as some mentioned here, but they make good power on the cheap


If you're not competing with either vehicle and you're happy with the sound, just enjoy it and don't look back. I seriously doubt any difference in your class D amps and the old class a/b would be discernible at highway speed. 
Those little Ion amps have me intrigued. Lots of positive reviews around on them.


----------



## DC/Hertz

So if you do compete and listen with the engine off we are forced to use amps using 40 year old tech?


----------



## DC/Hertz

I wonder if a $1200 Mosconi will fix my mirror rattling right over stage center?


----------



## rton20s

DC/Hertz said:


> I wonder if a $1200 Mosconi will fix my mirror rattling right over stage center?


It will if you bolt the Mosconi directly to the mirror.


----------



## benny z

https://youtu.be/1oMRPBg9ROE


----------



## Hillbilly SQ

benny z said:


> https://youtu.be/1oMRPBg9ROE


That really is a good solid sounding amp, lol.


----------



## mrichard89

Hillbilly SQ said:


> That really is a good solid sounding amp, lol.


Just ordered a couple yesterday. Hope they really do sound that good!


----------



## DeltaB

Hillbilly SQ said:


> That really is a good solid sounding amp, lol.


And I was just getting into the noise floor test before the cabinet resonance testing...


----------



## BrainMach1

Until you started to pound on it, that amp was dead silent with no coloration. Very transparent. 

Just don't pound on it. 

Sent from my SM-G955U using Tapatalk


----------



## audiocholic

DC/Hertz said:


> I wonder if a $1200 Mosconi will fix my mirror rattling right over stage center?



dont know the answer to that but it sure did make my car faster and fuel consumption is down by %10.


----------



## GEM592

Let me sum up this thread for you, because I've heard it many times before:

Class D is the bomb, and although we haven't perfected it yet, we're gonna. But with the "big power in a small package" feature a little so-and-so like you shouldn't care too much. How you gonna run big power and start your car too anyhow? So just lay your money down, and let technology do its thing yo.


----------



## DC/Hertz

audiocholic said:


> dont know the answer to that but it sure did make my car faster and fuel consumption is down by %10.


I got stickers already that add 100hp.


----------



## benny z

DC/Hertz said:


> I got stickers already that add 100hp.




Intoxalock?


----------



## DC/Hertz

benny z said:


> Intoxalock?


Nah. I’ve never been caught.


----------



## benny z

Lol!


----------



## Holmz

I am kinda old-school, and was told by the parents they only wanted to see A or A/B.
Bringing home a D would result in grounding.


----------



## DPGstereo

Usually guys in class D camp also believe active is superior to passive...


----------



## PPI_GUY

DC/Hertz said:


> So if you do compete and listen with the engine off we are forced to use amps using 40 year old tech?


Nope. But, if he falls within the parameters I listed there wouldn't seem to be any need to replace the amps he is already happy with either. 
I'm not a class a/b snob like some in this thread. Actually, I'm a big fan of the JL Audio XD amps. For their size, quality, price point and performance they're probably still one of the best buys out there.


----------



## sqnut

DPGstereo said:


> Usually guys in class D camp also believe active is superior to passive...


In a car active is *always* better than passive, regardless of the topology of the amp. Only caveat is, you should know how to tune and if you don't then yes, passive is better than a messed up active network.


----------



## DC/Hertz

If you don’t think active is superior then you don’t know how to listen. 
If you don’t know how to listen how can you say they sound different?


----------



## DeltaB

When it comes to passive crossovers, most don't have the knowledge to properly construct one. Fixed installations, and that includes vehicles, passive crossovers, properly implemented, can certainly do everything you may need.


----------



## sqnut

DeltaB said:


> When it comes to passive crossovers, most don't have the knowledge to properly construct one. Fixed installations, and that includes vehicles, passive crossovers, properly implemented, can certainly do everything you may need.


The engineering in the passive aside, most brand names don't allow bi-amping, so one can't TA each driver individually. Also, most brands run the tweeters much lower than they should in 2 way sets, there must be a million threads on here about, 'help my tweeters sound harsh'. Its quicker, easier and better to run active.


----------



## DeltaB

sqnut said:


> The engineering in the passive aside, most brand names don't allow bi-amping, so one can't TA each driver individually. Also, most brands run the tweeters much lower than they should in 2 way sets, there must be a million threads on here about, 'help my tweeters sound harsh'. Its quicker, easier and better to run active.


You can't set the engineering aside. You don't understand enough about passive crossovers or which type or order to use, to realize alignment is done by them, and part of one of the most basic design considerations. I'm not concerned with how many threads of ignorance may appear here, and by reason of saying something that is incorrect a million times doesn't make it any more true. Most of them are populated with very little understanding much like your assertion.

Linkwitz-Riley Crossovers: A Primer


----------



## DPGstereo

sqnut said:


> In a car active is *always* better than passive, regardless of the topology of the amp. Only caveat is, you should know how to tune and if you don't then yes, passive is better than a messed up active network.





"always" ??? I'm using a No 7, with Crossblock...bi-amp'd...tweeter and 3" mid are close together. I've considered active (using 8to12 Aerospace), but considered all the time and effort that went into the design of the Crossblock. I know it's been argued both ways, but how many have actually tried it active vs. passive in a properly tuned, hi-end system? 

I look at what the home speaker designs are..when talking about $250k pair of speakers...they could use any crossover design they want.

My opinion is that class D and active are a more cost effective solution for car audio...not necessarily the best for SQ...but good enough for many.

"What about all the guys winning competitions with class D and active.." Those guys will win with A/B and passive...question is, which one will sound better? Maybe a challenge for identical: car, speaker location, ect. build.



.


----------



## ca90ss

The problem with most passive crossovers that come with car audio speaker sets are that they are a one size fits all approach. They can't compensate for one install where the woofer is right next to the tweeter and another where they're 3' apart. You can build a custom passive but by the time you buy all of the components to build one, build it, test it and then buy more components to adjust it from there it's cheaper, faster and easier to just go active.


----------



## ca90ss

DPGstereo said:


> "
> 
> I look at what the home speaker designs are..when talking about $250k pair of speakers...they could use any crossover design they want.


The difference is that with a set of home speakers the cabinet and positioning of the drivers relative to one another doesn't change. A set of car speakers is installed differently in every car.


----------



## DeltaB

ca90ss said:


> The problem with most passive crossovers that come with car audio speaker sets are that they are a one size fits all approach. They can't compensate for one install where the woofer is right next to the tweeter and another where they're 3' apart. You can build a custom passive but by the time you buy all of the components to build one, build it, test it and then buy more components to adjust it from there it's cheaper, faster and easier to just go active.


This is why I have said time and again, proper selection and implementation of components is required to save yourself the heartache of poor design. Physics doesn't take a day off when working with a vehicle, nor does the placement change daily after an install.

I will agree that most over the counter one-size-fits-all is not the best, but if you know how to design a system, passive crossovers are much less expensive, especially considering the expense of implementing an active system.


----------



## ca90ss

DeltaB said:


> but if you know how to design a system, passive crossovers are much less expensive, especially considering the expense of implementing an active system.


Unless you're using bottom of the barrel components in your crossover I don't see it being significantly less expensive. I've never seen a passive be perfect on the first try so beyond the initial parts you'll also need a supply of parts to fine tune it from there and once you do perfect it it's only good for that particular install. A dsp can be had for ~$100 these days and an additional amp can be had for the same. Then when you change cars the active system can be installed in the new car with no additional expense while a passive will need to be completely redesigned.


----------



## DeltaB

ca90ss said:


> Unless you're using bottom of the barrel components in your crossover I don't see it being significantly less expensive. I've never seen a passive be perfect on the first try so beyond the initial parts you'll also need a supply of parts to fine tune it from there and once you do perfect it it's only good for that particular install. A dsp can be had for ~$100 these days and an additional amp can be had for the same. Then when you change cars the active system can be installed in the new car with no additional expense while a passive will need to be completely redesigned.


I have yet to remove a system from one vehicle to install it in another. And physics doesn't take a day off when working with a vehicle. If you don't know how to wind a coil, or select components for a crossover, you probably don't know how to measure for voice coil alignment or build a crossover. And it doesn't cost multi-hundred dollars to make one, or four.


----------



## Hillbilly SQ

Guess I'll stay ignorant and keep running active. Passive sounds like more trouble and expense than it's worth to me!


----------



## ca90ss

I don't know if you're being intentionally obtuse or haven't priced crossover components lately or just use the absolute cheapest parts you can find or what but to do what a dsp can do requires more than just a couple components slapped together. Not to mention the extra time involved in designing and building a passive. I don't know what your spare time is worth but mine is worth a whole lot more than $.10 an hour to me.


----------



## Hillbilly SQ

Guess if you're retired/disabled and need to keep your mind busy to prevent Alzheimer's...


----------



## Holmz

There was another thread about the importance of damping factor. The one area where an active excels is in having direct control over the speaker. Outside of the passive cross over's pass band the impedance that the amp sees makes its damping factor (control) head to zero.

In the context of this particular thread, lets say that class D has many advantages.
But let's says that SQ was not as good in the tweeter band.
So one could run class D sub, woofer and midrange, and a small class A for the tweeters.


----------



## DeltaB

Hillbilly SQ said:


> Guess if you're retired/disabled and need to keep your mind busy to prevent Alzheimer's...


That's incredibly rude, totally uncalled for and inaccurate. I've been home brewing my own components for decades. I guess if you don't possess the skill set to do your own, belittle anyone who does? That's the mark of a real mental midget.


----------



## DeltaB

ca90ss said:


> I don't know if you're being intentionally obtuse or haven't priced crossover components lately or just use the absolute cheapest parts you can find or what but to do what a dsp can do requires more than just a couple components slapped together. Not to mention the extra time involved in designing and building a passive. I don't know what your spare time is worth but mine is worth a whole lot more than $.10 an hour to me.


How much do you pay someone to come in and wipe your butt when you finish a crap? Do you not have any hobbies? Do you not do things simply for their enjoyment value? That kind of thought process is kind of screwed up. My spare time is my spare time to do with whatever I please.


----------



## ca90ss

DeltaB said:


> How much do you pay someone to come in and wipe your butt when you finish a crap?


That's between me and Raoul.


> Do you not have any hobbies? Do you not do things simply for their enjoyment value? That kind of thought process is kind of screwed up. My spare time is my spare time to do with whatever I please.


Just because it's your hobby doesn't mean everyone shares the same level of interest in it and is willing to put forth the same amount of time and effort. Some of us just want to get things done so we can move on to other things we enjoy.


----------



## DeltaB

ca90ss said:


> Just because it's your hobby doesn't mean everyone shares the same level of interest in it and is willing to put forth the same amount of time and effort. Some of us just want to get things done so we can move on to other things we enjoy.


Never asked anyone to. The real issue isn't about time, it's about the knowledge to do so. Please help me out here, define DIY


----------



## ca90ss

DeltaB said:


> Never asked anyone to. The real issue isn't about time, it's about the knowledge to do so.


These days knowledge is easy to acquire. For most of us spare time isn't.


----------



## DeltaB

ca90ss said:


> These days knowledge is easy to acquire. For most of us spare time isn't.


I work a busy life as well, and thank God my job pays me well enough I have the luxury to purchase whatever device I might want. If knowledge was so easy to acquire, then please explain why so many are lacking in it. Could it be some don't have the skill set to actually do research? Also, you didn't define the very namesake of the site, so I ask again, please define DIY. It's splattered on every page here.


----------



## ca90ss

DeltaB said:


> I work a busy life as well, and thank God my job pays me well enough I have the luxury to purchase whatever device I might want. However, you didn't define the very namesake of the site, so I ask again, please define DIY. It's splattered on every page here.


You added that after I had already quoted you. There isn't a set definition of DIY here and your definition will be different than the next person. Maybe you see winding your own inductors as DIY, maybe to the next person it's only DIY if they mined the raw materials to make the components that the inductor is made of and maybe to the next person it isn't DIY unless you made the tools that mined the raw materials that made the inductor. The point is, you can always take it a step further. So what's your point? What do you consider DIY? Just because you take one aspect further than the next guy doesn't make you special.


----------



## GEM592

ca90ss said:


> ... you made the tools that mined the raw materials that made the inductor.


See, right there is where we differ. I would have first mined the materials to make those tools.


----------



## ca90ss

GEM592 said:


> See, right there is where we differ. I would have first mined the materials to make those tools.


Awww man, here I was thinking I was hot stuff and then you go and do me one better.


----------



## GEM592

ca90ss said:


> Awww man, here I was thinking I was hot stuff and then you go and do me one better.


Thank you. I'm here all week.


----------



## Holmz

Hillbilly SQ said:


> Guess if you're retired/disabled and need to keep your mind busy to prevent Alzheimer's...


I am not DeltaB's biggest fan, but it seems a cheap shot to address his age.
If Mr/Dr Linkwitz was posting you would not likely attack his age.

IMO there are enough things to pick apart in the posts without resorting to age-bias.




DeltaB said:


> ...
> Please help me out here, define DIY


"Do" and "Yourself" are pretty common English words.
So "It" can likely refer to:
- Installs and enclosures
- Cabling - RCAs/Balanced, speakers, grounds, and power
- Components
- DSP and tuning
- Help with selection of gear

And then there are people catering toward selling to a DIY market
People looking for installers and suppliers
... and other people generally interested.


----------



## PPI_GUY

I have a Precision Power 356cs component set (6.5) that is bi-ampable. So, they should allow for time alignment although, I have not tried that yet. Would still like to. However, the crossover modules themselves are enormous and would be very hard to hide in the vehicle interior. So, there's a reason to go active in and of itself. They do look to be very well constructed and thought out though.


----------



## sqnut

DeltaB said:


> Most of them are populated with very little understanding much like your assertion.
> 
> Linkwitz-Riley Crossovers: A Primer


Dude, you can't hear the difference between your 2ch and your car, and you're calling me ignorant of facts?:laugh:

All that knowledge in your head is just theory, car audio is all application. You can't fully apply what you know, if you can't hear the difference. Try this.

Harman How to Listen: Welcome to How to Listen!


----------



## sqnut

DPGstereo said:


> "always" ??? .....................


If you have a decent dsp and you know how to tune, yes always.


----------



## DPGstereo

sqnut said:


> If you have a decent dsp and you know how to tune, yes always.



Well...that's just wrong.



.


----------



## el_bob-o

It boggles my mind to think about the trial and error it would take me to build proper passive crossovers that are perfect for my specific vehicle. I am admittedly not an expert in passive network design nor am I overly well versed in tuning a fully active setup. That being said, I think I would get much better results given a limited amount of time (which is all I have available) tuning an active setup. The tools available too me such as Room EQ Wizard make an active setup much less daunting than a passive setup. 

If I had more knowledge, experience and time to acquire those attributes in regards to passive network designs I might have a different view. With my current limitations installing and tuning an active setup nicely fits into my DIY aspirations.


----------



## sqnut

DPGstereo said:


> Well...that's just wrong..


Nope, its a fact. But you are entitled to your opinion, even if it contradicts facts, it's in vogue these days.


----------



## DeltaB

ca90ss said:


> You added that after I had already quoted you. There isn't a set definition of DIY here and your definition will be different than the next person. Maybe you see winding your own inductors as DIY, maybe to the next person it's only DIY if they mined the raw materials to make the components that the inductor is made of and maybe to the next person it isn't DIY unless you made the tools that mined the raw materials that made the inductor. The point is, you can always take it a step further. So what's your point? What do you consider DIY? Just because you take one aspect further than the next guy doesn't make you special.


My point? Don't dis folks who may DIY. You're a moderator on a DIY site.


----------



## DeltaB

sqnut said:


> Dude, you can't hear the difference between your 2ch and your car, and you're calling me ignorant of facts?:laugh:
> 
> All that knowledge in your head is just theory, car audio is all application. You can't fully apply what you know, if you can't hear the difference. Try this.
> 
> Harman How to Listen: Welcome to How to Listen!


You haven't a clue as to what you are saying here. Sad but true.


----------



## DeltaB

GEM592 said:


> See, right there is where we differ. I would have first mined the materials to make those tools.


I find it interesting that folks who may take weeks to work an A pillar over with fiberglass to enclose a tweeter, or DIY an enclosure for a sub, or spend days and weeks on treatment and speaker mounting in doors don't seem to ever meet the kind of resistance and scorn, (seeing that time is such a precious factor, which is nothing more than a smokescreen to hide the ignorance of actually knowing passive device construction) and the hypocrisy of those who haven't taken the time to design and implement a system that properly utilizes passive crossover components. The true issue isn't time, it's ignorance.


----------



## DeltaB

el_bob-o said:


> It boggles my mind to think about the trial and error it would take me to build proper passive crossovers that are perfect for my specific vehicle. I am admittedly not an expert in passive network design nor am I overly well versed in tuning a fully active setup. That being said, I think I would get much better results given a limited amount of time (which is all I have available) tuning an active setup. The tools available too me such as Room EQ Wizard make an active setup much less daunting than a passive setup.
> 
> If I had more knowledge, experience and time to acquire those attributes in regards to passive network designs I might have a different view. With my current limitations installing and tuning an active setup nicely fits into my DIY aspirations.


The values of the L/C components for a given frequency for a given load (ohms) are fixed. Once the slope is chosen, you then select it's order to move the driver alignment, and since this is fixed in time, each order, or degree, of a crossover network contributes ±45° of phase shift at the crossover frequency. You need to know what the crossover point is, the ohm rating of the speaker, and the distance from the listening point to the driver's voice coil. It's not as "trial and error" as some would lead you to believe. An understanding of acoustic lobing will help you to understand what this is about.


----------



## sqnut

DeltaB said:


> You haven't a clue as to what you are saying here. Sad but true.


Download the software and play it on your monitors. Select band ID training and in the menu, select 24 bands, set the resolution to +/- 0.5db, set the Q to 4 and you've got yourself a 24 band equalizer. Now select a song from one of the four choices, for your convenience each file is available in 48 and 96K resolution. 

Now when you run the test, the software will pick one of the 24 bands and either boost or cut it by 0.5db. You can toggle back and forth between flat and eq'd, then pick the frequency and if it's a boost or cut. Chances are at this resolution, you'll struggle to hear a difference, much less be able to pick the frequency. You need to be able to call it correctly at least 70% of the time, if you have any hope of getting the car sounding right.

Now go back and change the resolution to +/- 6db and repeat. Now I bet you hear the difference even if you still can't pick the frequency. To hear how bad a car can sound you have to hear how good a decent 2ch is, when you do you will have learned to hear the difference. 

Thanks to all your knowledge, you have a static mindset and how you do things is now a holy cow for you. In a car, the impact of the environment forces us to do things we wouldn't in a normal room, but again you continue to ignore the role the car plays in what you hear. Who's ignorant?


----------



## DeltaB

sqnut said:


> Download the software and play it on your monitors. Select band ID training and in the menu, select 24 bands, set the resolution to +/- 0.5db, set the Q to 4 and you've got yourself a 24 band equalizer. Now select a song from one of the four choices, for your convenience each file is available in 48 and 96K resolution.
> 
> Now when you run the test, the software will pick one of the 24 bands and either boost or cut it by 0.5db. You can toggle back and forth between flat and eq'd, then pick the frequency and if it's a boost or cut. Chances are at this resolution, you'll struggle to hear a difference, much less be able to pick the frequency. You need to be able to call it correctly at least 70% of the time, if you have any hope of getting the car sounding right.
> 
> Now go back and change the resolution to +/- 6db and repeat. Now I bet you hear the difference even if you still can't pick the frequency. To hear how bad a car can sound you have to hear how good a decent 2ch is, when you do you will have learned to hear the difference.
> 
> Thanks to all your knowledge, you have a static mindset and how you do things is now a holy cow for you. In a car the impact of the environment forces us to do things you wouldn't in a normal room, but you continue to ignore the role of the car in what you hear.


Obviously you have some felt need to justify your poor understanding. Physics doesn't take a day off when it comes to a vehicle. As before, I should have left you on ignore. You have a great life.


----------



## sqnut

DeltaB said:


> Obviously you have some felt need to justify your poor understanding. Physics doesn't take a day off when it comes to a vehicle. As before, I should have left you on ignore. You have a great life.


No it doesn't take the day off, in fact it gets way more hands on, but you're not hearing that difference. :shrug:


----------



## DC/Hertz

People are going to spend time DIYing an install. When you can go out and get a active crossover cheap, and most amps come with them these days.


----------



## Hillbilly SQ

DeltaB said:


> That's incredibly rude, totally uncalled for and inaccurate. I've been home brewing my own components for decades. I guess if you don't possess the skill set to do your own, belittle anyone who does? That's the mark of a real mental midget.


Get bent out of shape much?


----------



## Hillbilly SQ

ALRIGHT FOLKS LISTEN UP! I was in no way attacking DeltaB's age. I didn't intend it to be a cheap shot. If you took it that way I do apologize but it won't change how I really am. If you have really thin skin I suggest you put me on "ignore".


----------



## Hillbilly SQ

And why is it always home audio guys that think we car audio guys don't have a clue? Do they not understand what the interior of a car does to phase and frequency response? One thing you'll NEVER see me run in a car ever again are passive crossovers. I have better things to do with my time that to dick around with passive crossovers. And just because you have a passive crossover doesn't mean you're immune to phase issues once it's in the car. You can adjust acoustical phase with a good dsp in the matter of seconds. Good luck tweaking a passive crossover in that amount of time.


----------



## rob feature

Hillbilly SQ said:


> And why is it always home audio guys that think we car audio guys don't have a clue?


They listen to records - there's no helping that bunch. :goofy:


----------



## DeltaB

rob feature said:


> They listen to records - there's no helping that bunch. :goofy:


Assertions about someone whom you have never met, don't understand where they have been, or their career, no idea what exposure to any type of audio, and making stereotypical assertions based solely from ignorance? Rather immature don't you think?


----------



## DC/Hertz

DeltaB said:


> Assertions about someone whom you have never met, don't understand where they have been, or their career, no idea what exposure to any type of audio, and making stereotypical assertions based solely from ignorance? Rather immature don't you think?


Well aren’t you just a hypocrite


----------



## Jeffdachefz

swoardrider said:


> I absolutely, positively, without a doubt love people like you and your 30,000 watts, that basically take the Greek Theatre's sound system and put it in your car, thinking that rattling the neighbors fine china is a "good sounding" system
> This is a Class D SQ thread, or (lack there of SQ). There's already morons in here quoting technology that's yet to be built for 12V. Dipshits in here quoting nonsense that have never picked up a musical instrument in there life. And now bass heads who think cheap flea market components sound as good as precision built transducers and amplifiers. Go over and troll the SPL forums


you are the only troll here that concentrates on snake oil lmfao.. complete and total joke of a person. Go play classical instruments, its the only way you'll ever have something realistic sounding in your life audio wise. pathetic.


----------



## rob feature

DeltaB said:


> Assertions about someone whom you have never met, don't understand where they have been, or their career, no idea what exposure to any type of audio, and making stereotypical assertions based solely from ignorance? Rather immature don't you think?


lulz


----------



## Hillbilly SQ

I still feel like it's wrong to tell someone the way they skin a cat is wrong when it's a perfectly accepted method of bending the signal. This is car audio after all. Designing passive crossovers is a hobby just like anything else you do to pass your spare time and even done by some for a living. We don't use a dsp because we're ignorant. We use one because of the near endless possibilities they give us.


----------



## DeltaB

Hillbilly SQ said:


> I still feel like it's wrong to tell someone the way they skin a cat is wrong when it's a perfectly accepted method of bending the signal. This is car audio after all. Designing passive crossovers is a hobby just like anything else you do to pass your spare time and even done by some for a living. We don't use a dsp because we're ignorant. We use one because of the near endless possibilities they give us.


You drove the bus into the ditch thinking I don't use DSP or EQ. I prefer to do it before the DAC. I also prefer to utilize the right tool to meet my objective. I don't need to spend the additional resources for bi-amp. I already know how to manipulate the acoustic lobes for the doors with passives.

I really shouldn't have to do remedial English for those who come here, but I also want you to understand that when I use the word "ignorance" it doesn't mean "stupid." Ignorance simply means, "lack of knowledge or information. To not know" Comes through the French, same root as to ignore, meaning to neglect to overlook.


----------



## DC/Hertz

DeltaB said:


> You drove the bus into the ditch thinking I don't use DSP or EQ. I prefer to do it before the DAC. I also prefer to utilize the right tool to meet my objective. I don't need to spend the additional resources for bi-amp. I already know how to manipulate the acoustic lobes for the doors with passives.


Have you ever had the car judged? 
Serious question. Having a outside prospective is really helpful if you can be humble.


----------



## Niebur3

DC/Hertz said:


> Have you ever had the car judged?
> Serious question. Having a outside prospective is really helpful if you can *be humble*.


----------



## madmaxz

i know theres not too many rockford fans on this site but the rockford AD amps specifically in my case the t1000-4ad and t800-4ad sound fantastic.


----------



## ca90ss

DeltaB said:


> (seeing that time is such a precious factor, which is nothing more than a smokescreen to hide the ignorance of actually knowing passive device construction) and the hypocrisy of those who haven't taken the time to design and implement a system that properly utilizes passive crossover components. The true issue isn't time, it's ignorance.





DeltaB said:


> Assertions about someone whom you have never met, don't understand where they have been, or their career, no idea what exposure to any type of audio, and making stereotypical assertions based solely from ignorance? *Rather immature don't you think*?


I couldn't agree more.


----------



## rob feature

Guys - it was a joke. Not a jab at anyone - simply a joke about records. The reading into it is sorta baffling really.


----------



## DPGstereo

Hillbilly SQ said:


> And why is it always home audio guys that think we car audio guys don't have a clue? Do they not understand what the interior of a car does to phase and frequency response? One thing you'll NEVER see me run in a car ever again are passive crossovers. I have better things to do with my time that to dick around with passive crossovers. And just because you have a passive crossover doesn't mean you're immune to phase issues once it's in the car. You can adjust acoustical phase with a good dsp in the matter of seconds. Good luck tweaking a passive crossover in that amount of time.


Probably has more to do with how close you are to the driver's side speakers in relation to the rest. And the passive Crossblock I use is not what you'd normally get with a component set. I, of course still take advantage of the modern dsp for t/a, eq and limited crossover. Class A/B still sounds better. :laugh:


----------



## rc10mike

As a fan of car audio, home audio and portable audio. Car audio guys are the most realistic folks out there. The home audio and headfi community believe in some of the dumbest crap Ive ever seen, like diamond plated platinum core headphone cables and ceramic power cable lifters that cost 5k. They firmly believe in it too. Its sad honestly.


----------



## Hillbilly SQ

rc10mike said:


> As a fan of car audio, home audio and portable audio. Car audio guys are the most realistic folks out there. The home audio and headfi community believe in some of the dumbest crap Ive ever seen, like diamond plated platinum core headphone cables and ceramic power cable lifters that cost 5k. They firmly believe in it too. Its sad honestly.


I'm in the wrong business!


----------



## Hillbilly SQ

DPGstereo said:


> Probably has more to do with how close you are to the driver's side speakers in relation to the rest. And the passive Crossblock I use is not what you'd normally get with a component set. I, of course still take advantage of the modern dsp for t/a, eq and limited crossover. Class A/B still sounds better. :laugh:


Meh, we're all entitled to our opinion. I still like the flexibility of dsp crossovers. At least my powerful 6ch amp fits in my odd spare tire well out of sight out of mind


----------



## Izay123

rc10mike said:


> As a fan of car audio, home audio and portable audio. Car audio guys are the most realistic folks out there. The home audio and headfi community believe in some of the dumbest crap Ive ever seen, like diamond plated platinum core headphone cables and ceramic power cable lifters that cost 5k. They firmly believe in it too. Its sad honestly.




I see what you're saying... I feel like a great number of Car Audio folks are pretty far out on the other side of the spectrum though. There is a tremendous amount of misinformation out there, & those that spend years looking for the Ultimate drivers for $5ea. 

Some People in car audio seem to be Quick to dismiss the value of anything they can't Measure with an RTA, Oscope, & DMM. 

I'd prefer to be surrounded by Hybrid-minded folks: people still listening with their ears & exploring both the Electromechanical & Fluid Dynamic Engineering aspects of the hobby, WHILE AT THE SAME TIME Exploring the Artistry that is involved in designing, building, & tuning most of the best-performing Sound systems around.


----------



## ca90ss

rob feature said:


> Guys - it was a joke. Not a jab at anyone - simply a joke about records. The reading into it is sorta baffling really.


My post was directed towards Delta and the hypocrisy of him crying about someone making assumptions about him right after he did the same thing to someone else.


----------



## ChrisB

Hillbilly SQ said:


> I still feel like it's wrong to tell someone the way they skin a cat is wrong when it's a perfectly accepted method of bending the signal. This is car audio after all. Designing passive crossovers is a hobby just like anything else you do to pass your spare time and even done by some for a living. We don't use a dsp because we're ignorant. We use one because of the near endless possibilities they give us.


Designing custom passive crossovers for the automotive environment after having your speakers measured to take all the extraneous variables into effect really sucks when you blow a driver and can't obtain an exact replacement. Guess what, you get to start the process all over again. YAY!

Oh, and even if you purchase the same exact speaker, you may not obtain an exact replacement that measures the same. I watched a good friend of mine nearly drive himself insane with his own car and a LEAP speaker analysis setup.

EDIT: When he finally finished his car, it sounded awesome. He sold it a few months later after putting over 2000 hours into the sound system, lol. He went a little overboard with the dashboard and the line driver array designed to give him the perfect stereo image, no matter where his head was.

Just to give you an example of how he liked to experiment... His last home setup had two towers with sixteen, yes, SIXTEEN Scanspeak Illuminators in each tower along with a mid and tweeter to match! At least he is retired now and has lots of time and money to play around with.


----------



## DeltaB

ca90ss said:


> My post was directed towards Delta and the hypocrisy of him crying about someone making assumptions about him right after he did the same thing to someone else.


I really shouldn't have to do remedial English for those who come here, but I also want you to understand that when I use the word "ignorance" it doesn't mean "stupid." Ignorance simply means, "lack of knowledge or information. To not know."

I knew exactly what you were asserting, doesn't make it correct though.


----------



## ca90ss

DeltaB said:


> I really shouldn't have to do remedial English for those who come here, but I also want you to understand that when I use the word "ignorance" it doesn't mean "stupid." Ignorance simply means, "lack of knowledge or information. To not know."
> 
> I knew exactly what you were asserting, doesn't make it correct though.


I know what you meant, it still doesn't change the fact that you made an assumption without knowing what knowledge I may or may not possess which is exactly what you were complaining about someone doing to you.


----------



## Izay123

ca90ss & DeltaB

So are you guys gonna solve this like real men & Meetup for a Face-to-face Duel--Like old times?

Or a Soundoff--& the loser has to do his next build the way the other guy says? 

You guys are bickering like teenage sisters. Sheesh.


----------



## DeltaB

ca90ss said:


> I know what you meant, it still doesn't change the fact that you made an assumption without knowing what knowledge I may or may not possess which is exactly what you were complaining about someone doing to you.


My comment to GEM wasn't about you. Get over it.


----------



## Patriot83

So...getting back to D class amps. I got to hear a recently installed system in a jeep. JL XD amps, focal krx3's and JL subs. It sounded clean but kind of sterile. Hard to describe. No excitement and the guy spent 5 grand for that system. I got out of the jeep and thought no way am I buying one of those amps. Maybe the jeep acoustics had something to do with it but it was disappointing to me for 5G's.


----------



## mitchell0715

Patriot83 said:


> So...getting back to D class amps. I got to hear a recently installed system in a jeep. JL XD amps, focal krx3's and JL subs. It sounded clean but kind of sterile. Hard to describe. No excitement and the guy spent 5 grand for that system. I got out of the jeep and thought no way am I buying one of those amps. Maybe the jeep acoustics had something to do with it but it was disappointing to me for 5G's.


5k for install and equipment is vastly different than 5k for equipment


----------



## Patriot83

mitchell0715 said:


> 5k for install and equipment is vastly different than 5k for equipment


Oh I know. Just saying it sounded kind of bland for the great equipment in there. I expected the XD/krx3 combo to sound better


----------



## Patriot83

I have to say that xd/krx3 combo sounded a lot better than a helix/HAT combo from another shop though. That guy obviously didn't know how to tune that helix dsp and it was his car. It sounded like complete garbage. The differences in install and tuning can be shocking. I feel like it's best to get the best install/tuning than the best equipment.


----------



## Jeffdachefz

Patriot83 said:


> I have to say that xd/krx3 combo sounded a lot better than a helix/HAT combo from another shop though. That guy obviously didn't know how to tune that helix dsp and it was his car. It sounded like complete garbage. The differences in install and tuning can be shocking. I feel like it's best to get the best install/tuning than the best equipment.


if you understand this part, why would you make such an ignorant statement to blame all the lifelessness and sterility on the type of amp used? WHAT????? LOL


----------



## gjmallory

Jeffdachefz said:


> if you understand this part, why would you make such an ignorant statement to blame all the lifelessness and sterility on the type of amp used? WHAT????? LOL




Dude. Chill. 


Sent from my iPhone using Tapatalk Pro


----------



## Ziggyrama

Patriot83 said:


> So...getting back to D class amps. I got to hear a recently installed system in a jeep. JL XD amps, focal krx3's and JL subs. It sounded clean but kind of sterile. Hard to describe. No excitement and the guy spent 5 grand for that system. I got out of the jeep and thought no way am I buying one of those amps. Maybe the jeep acoustics had something to do with it but it was disappointing to me for 5G's.


Most likely other factors are at play. The primary one being the tuning of the setup and how it combined with the accoustics in that car. I am sure the amp is very capable and of course those drivers are more than fine. Tuning greatly affects tonality, imaging, the stage and noise so if you don't get that right, it can be a difference between a setup that will leave you smiling vs. meh. Anecdodal evidence, 2 years ago I demoed my setup at an audio meet and people liked it but it wasn't ground breaking. I was a tuning novice and I was obviously still learning how to get the most out of my hardware. I came back last year and the same gear blew people away. All I did is adjusted my tune in several ways. General feedback was super positive. Moral of the story, devil's in the details. Next time, drill in deeper and ask how exactly it was put together. That will give you an idea of what you are listening to.

Sent from my Pixel using Tapatalk


----------



## Patriot83

Jeffdachefz said:


> if you understand this part, why would you make such an ignorant statement to blame all the lifelessness and sterility on the type of amp used? WHAT????? LOL


 Looks like someone hasn't gotten any for awhile


----------



## Patriot83

Ziggyrama said:


> Most likely other factors are at play. The primary one being the tuning of the setup and how it combined with the accoustics in that car. I am sure the amp is very capable and of course those drivers are more than fine. Tuning greatly affects tonality, imaging, the stage and noise so if you don't get that right, it can be a difference between a setup that will leave you smiling vs. meh. Anecdodal evidence, 2 years ago I demoed my setup at an audio meet and people liked it but it wasn't ground breaking. I was a tuning novice and I was obviously still learning how to get the most out of my hardware. I came back last year and the same gear blew people away. All I did is adjusted my tune in several ways. General feedback was super positive. Moral of the story, devil's in the details. Next time, drill in deeper and ask how exactly it was put together. That will give you an idea of what you are listening to.
> 
> Sent from my Pixel using Tapatalk


Yeah it was a very weird set up in that jeep. I know there's a lot of love on here for the xd amps but you know when you hear something and you expect more, you feel disappointed. Highly doubt it was the speakers. I'll try to keep an open mind till I hear another xd set up


----------



## Ziggyrama

Patriot83 said:


> Yeah it was a very weird set up in that jeep. I know there's a lot of love on here for the xd amps but you know when you hear something and you expect more, you feel disappointed. Highly doubt it was the speakers. I'll try to keep an open mind till I hear another xd set up


Yup, I have no extra love for those amps. Just simply sharing what I have seen myself. If the sound was lifeless, odds are, the way it was tuned had more to do with it than other factors. Just a few dBs off in the right frequencies can suck the life out of the recording. Also, and this is important, it is always better to eval using material you are familiar with. If you sit down and already know what it is supposed to sound like, it removes another variable off the table which is bad recording. Some tracks just aren't that good. That is why judges have their own reference materials when they evaluate your system. Not always, but odds are, if a lot of people that generally know good sound agree the amps sound good, they probably do sound good.....to them 

Sent from my Pixel using Tapatalk


----------



## SnakeOil

I personally try to not listen to the amp since that’s not really what you are hearing.


----------



## mitchell0715

Patriot83 said:


> Looks like someone hasn't gotten any for awhile


this is funny as fk if you actually knew jeff lol dude probably gets more than you've gotten in the last 5 years. most people who are happy to say whatever they want are the complete opposite of insecure because they dont need to suck up to get laid 

he's just tired of people making statements about class d that they know aren't completely true. the SQ crowd is notorious for that crap

kinda like the whole 'lOl tHaT fUlL BRidGe WiLL CaTCH FirE"


----------



## Patriot83

mitchell0715 said:


> this is funny as fk if you actually knew jeff lol dude probably gets more than you've gotten in the last 5 years
> 
> he's just tired of people making statements about class d that they know aren't completely true. the SQ crowd is notorious for that crap
> 
> kinda like the whole 'lOl tHaT fUlL BRidGe WiLL CaTCH FirE"


hahaha, don't know "jeff" or you. You don't know me either or "how much I get". You don't sound very smart. How do you know what he's tired of? Did you ask him? And what is completely true is that set up I heard was disappointing. You assume a lot of things. I have nothing against class d amps. I'm actually considering getting one. Just probably not the XD.


----------



## SnakeOil

The XDs and HDs and Slash amps don’t seem to have much in the way of value. 
That has nothing to do with how they sound. 
They are not small or big on power compared to whats out there these days. No fancy networks. 
The RDs seem ok for their price point but it’s not that ok. 
Maybe I’m missing something, even in the early 2000s if you where not a JL fanboy there where better equipment to be had.


----------



## Babs

I have a hard time really faulting my XD’s (two XD1000/5v2). While I do get the upgrade bug on occasion, these have really served me well. I’m sure there are better or more power-per-channel amps out there in some class AB or D, they kinda get the job done. 


Sent from my iPhone using Tapatalk Pro


----------



## JVD240

The JL XD is fine.

It's ridiculous to get in an unknown vehicle with unknown tune/install and say "these amps sound bad."

Simple as that.


----------



## PPI_GUY

SnakeOil said:


> The XDs and HDs and Slash amps don’t seem to have much in the way of value.
> That has nothing to do with how they sound.
> They are not small or big on power compared to whats out there these days. No fancy networks.
> The RDs seem ok for their price point but it’s not that ok.
> Maybe I’m missing something, even in the early 2000s if you where not a JL fanboy there where better equipment to be had.


Not sure what you mean by value. Are the XD's the cheapest you'll find in their power range? Probably not but, they have quite a bit of R&D behind them. Their designs are proprietary and not some off the shelf board stuffed into a generic heat sink either. 
I do know they are approx. 10%-15% underrated so, I guess there's some value there. Their switching frequency is 400 kHz which I'd say is still pretty good even in 2018. 
I'd also say the XD amps are quite compact, especially since their design hasn't changed in the 7-8 years since they were released. There's plenty of copycat designs around that fall short. 
I have personally owned the XD amps in the past and they didn't disappoint me in either performance or sound quality. I'd gladly buy them again.
Quality and value shouldn't be based on bells & whistles IMO. It should be based on a proven, durable product that does what it advertises. 


BTW, if I sat down in a vehicle and thought the sound was sterile or lifeless, the system's amplification would be the last component I'd pin it on.


----------



## gjmallory

PPI_GUY said:


> BTW, if I sat down in a vehicle and thought the sound was sterile or lifeless, the system's amplification would be the last component I'd pin it on.



Definitely have to agree with @PPI_GUY on this. Based on how I think most would troubleshoot the described issue, amps are the one of the last thing that I would look at.

I've never owned a JL amp, but I know they are know for high quality in car and home theater. JL Audio has always seems like a Rolex to me. I could buy it... But do I really want to pay the amount of money required for that level of quality/fit & finish?




Sent from my iPhone using Tapatalk Pro


----------



## Jeffdachefz

wow, cant even take a joke sheesh. Must be masssively butt hurt from me pointing out the obvious flaws in his assessments.




Izay123 said:


> ca90ss & DeltaB
> 
> So are you guys gonna solve this like real men & Meetup for a Face-to-face Duel--Like old times?
> 
> Or a Soundoff--& the loser has to do his next build the way the other guy says?
> 
> You guys are bickering like teenage sisters. Sheesh.


Just saw this lmao, with these guys it'll probably end up in a slap fight with their eyes closed.


----------



## SnakeOil

PPI_GUY said:


> Not sure what you mean by value. Are the XD's the cheapest you'll find in their power range? Probably not but, they have quite a bit of R&D behind them. Their designs are proprietary and not some off the shelf board stuffed into a generic heat sink either.
> I do know they are approx. 10%-15% underrated so, I guess there's some value there. Their switching frequency is 400 kHz which I'd say is still pretty good even in 2018.
> I'd also say the XD amps are quite compact, especially since their design hasn't changed in the 7-8 years since they were released. There's plenty of copycat designs around that fall short.
> I have personally owned the XD amps in the past and they didn't disappoint me in either performance or sound quality. I'd gladly buy them again.
> Quality and value shouldn't be based on bells & whistles IMO. It should be based on a proven, durable product that does what it advertises.
> 
> 
> BTW, if I sat down in a vehicle and thought the sound was sterile or lifeless, the system's amplification would be the last component I'd pin it on.


I’m sure they are fine amps but not for what they cost. 
Don’t forget how small MMATS was making amps 20 years ago.


----------



## rob feature

SnakeOil said:


> I’m sure they are fine amps but not for what they cost.
> Don’t forget how small MMATS was making amps 20 years ago.


XDs are among the best amps I've ever used. They're transparent, make over rated power, built like tanks, are tiny for the power (except the 1000/1) and run very cool. Agreed that MSRP is lofty, but I've never paid even close to retail for one. The RD series is priced a lot more fairly and I'd be surprised if I could hear the difference in the RD and XD. Plus, IMHO, the RD looks better.


----------



## rob feature

PPI_GUY said:


> BTW, if I sat down in a vehicle and thought the sound was sterile or lifeless, the system's amplification would be the last component I'd pin it on.


+ꝏ

..


----------



## SnakeOil

Saying something makes over rated is fine. But are you still paying for it? In this case the answer is yes. 

Now bragging about something being underrated that’s cheaper matters.


----------



## JVD240

SnakeOil said:


> Saying something makes over rated is fine. But are you still paying for it? In this case the answer is yes.
> 
> Now bragging about something being underrated that’s cheaper matters.


Sure, if your only criteria for an amplifier is $/W. 

For most people that's not the case.

You've made it clear enough that you think JL is overpriced.


----------



## SnakeOil

I’ve made it clear I look for value in a product not the brand on it. 
Again it’s my opinion and how I shop. I don’t expect anyone else to do the same.


----------



## Dhorus

To me, the advantage of class D in car audio comes down to efficiency. 
My car's electric system is stock, and let's say I can draw 50A of current (just for argument sake) for my audio system. Using class D that means more watts than using class AB. And as I really don't want to mess with changing alternator / adding batteries, that's the deal breaker for me. 
Less heat is also a +, as my amps are installed under the trunk floor cover on my Santa Fe, never had any issues with them overheating. 

I use a Hertz HDP 4 and HDP 1 by the way.


----------



## Weightless

Patriot83 said:


> Great, another cyber troll. Stop trolling me dude and get a life. I make several trips to florida a year actually. If you actually live in florida. Making another trip soon. Would be more than glad to meet you and "talk" about your great knowledge. Shoot me your # and I'll be glad and text you when I'm headed down to make sure you're free that day/night. Pussies like you is what this site doesn't need


Holy over reaction, Batman! 

I think this falls more in line with what this forum doesn't need.



Sent from my SM-N920P using Tapatalk


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## gjmallory

JL isn't overpriced. You get certain things with the JL you don't with a Picasso nano. Amps are just like watches. A Rolex and a Casio tell the time. So, why would anyone spend extra on a Rolex? It is an instant heirloom/investment, it will last forever, it makes a statement about the wearer. If those very real benefits are NOT compelling, you buy the Casio. 


Sent from my iPhone using Tapatalk Pro


----------



## SnakeOil

Lol you can not compare any electronic to a watch. They lose value faster then a car or computer. Everyday something new and improved comes out.


----------



## PPI_GUY

SnakeOil said:


> Saying something makes over rated is fine. But are you still paying for it? In this case the answer is yes.
> 
> Now bragging about something being underrated that’s cheaper matters.


If an amplifier makes above rated power, that tells me that I can expect it to provide advertised specs at a minimum. So, IMO anything beyond that number is a nice bonus that I do not expect or consider in the cost. It also says something about how the product is built. 
Never known the XD's to get hot or fail as long as they are operated within factory parameters. I'm sure some have died but, with as many as JL has sold you will eventually get a few bad apples or idiots trying to push them too far. 

Back to cost. Again, we're talking about proprietary design here. Not a rehashed off the shelf thing. Doing it that way costs more money which is always passed along as a higher MSRP. 
Just depends on whether you're OK with a cookie-cutter variant or something unique.


----------



## PPI_GUY

Also, if you do not know the significance of the JL Audio Slash series amplifiers and what they brought to car audio, you might want to research the subject. Try keywords: "R.I.P.S Technology". Think I read somewhere recently that the 500/1 is the best selling car audio amplifier of all time as well. 

BTW, I don't work for JL or even own a JL product at this time. Just amazed that this idea that JL gear is over-priced is still being kicked around. LOL!


----------



## cobb2819

Stay on topic.


----------



## Patriot83

Weightless said:


> Holy over reaction, Batman!
> 
> I think this falls more in line with what this forum doesn't need.
> 
> 
> 
> Sent from my SM-N920P using Tapatalk


Yep, and this forum doesn't need people (Mitchell/Jeff) disrespecting someone because they stated an opinion about something. You disrespect, be prepared to get it back


----------



## I800C0LLECT

I'm a big fan of class D full range for the power efficiency. I've only used the JBL MS amps and my JL HD900/5. Both sounded phenomenal off my MS-8 using same vehicle, install, and speakers. I honestly didn't notice any difference in sound. I'm sold on full range class D

Sent from my SM-G955U using Tapatalk


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## thehatedguy

I have a few BNIB Soundigital GaNs waiting at UPS for me right now.


----------



## gjmallory

The crazy thing is that in home theater, Class D seems to generally be more expensive and considered higher-end? Of course, car audio has been the opposite. 

Since this is the "Technical & Advanced Car Audio Discussion" (believe it or not based on much of this thread...), does anyone have a *Technical or Advanced level* understanding of how home audio and 12v audio Class D may be different?


----------



## mitchell0715

Patriot83 said:


> Yep, and this forum doesn't need people (Mitchell/Jeff) disrespecting someone because they stated an opinion about something. You disrespect, be prepared to get it back


see:



cobb2819 said:


> Stay on topic.


----------



## rton20s

gjmallory said:


> The crazy thing is that in home theater, Class D seems to generally be more expensive and considered higher-end? Of course, car audio has been the opposite.
> 
> Since this is the "Technical & Advanced Car Audio Discussion" (believe it or not based on much of this thread...), does anyone have a *Technical or Advanced level* understanding of how home audio and 12v audio Class D may be different?


----------



## benny z

gjmallory said:


> Since this is the "Technical & Advanced Car Audio Discussion" (believe it or not based on much of this thread...), does anyone have a *Technical or Advanced level* understanding of how home audio and 12v audio Class D may be different?




Maybe the things that go on and off really fast go on and off really faster.


----------



## gijoe

gjmallory said:


> The crazy thing is that in home theater, Class D seems to generally be more expensive and considered higher-end? Of course, car audio has been the opposite.
> 
> Since this is the "Technical & Advanced Car Audio Discussion" (believe it or not based on much of this thread...), does anyone have a *Technical or Advanced level* understanding of how home audio and 12v audio Class D may be different?


There isn't a difference. Class D is here to stay, and I'm sure most manufactures will stop designing AB altogether before long. Class D amps are switching amplifiers, now that those switching frequencies are as high as they are class D can play full range as cleanly as any AB amp, while using a lot less energy. 

If you are trying to tune your system by swapping amps you will constantly be hearing things that either aren't there, or that could easily be changed with a basic EQ. As some have already mentioned, if the system sounds "sterile" or "lifeless" or (insert vaguely defined audiophile jargon here) the amp is the last place to look.


----------



## thehatedguy

The home world uses stuff that we don't get in 12 volt...like Pascal, Anaview, and Hypex UCD, though we can get Hypex based units from Biketronics (but not the UCD stuff).

Jeff Rowland Design uses Pascal boards/chip sets in their high end home products.


----------



## Mike Bober

One issue i did have with a class D amp was interference on AM radio if the amp was within 3 feet of the antenna or antenna wire. I moved it to another spot and it was a great amp.


----------



## Patriot83

Here's a quote from John at zapco when I inquired about their ST series amps

"The ST-5X II is class A/B in both highs and bass channel. Being class A/B it needs to be longer to dissipate the extra heat. If you are a sound quality listener and are not playing full power for long periods of time, I'd go with the 5X II, save a few bucks and get A/B sound. If you want to pound hard without the thermal issues I'd get the ST-5D and the sound should be close. We designed it to be better sounding than other class D amps so it is more expensive to build." 

So the 5X II is considerably cheaper than the 5D for close to the same power. Who knows if someone switched amps between the two if anyone could tell the difference.


----------



## SnakeOil

Patriot83 said:


> Here's a quote from John at zapco when I inquired about their ST series amps
> 
> "The ST-5X II is class A/B in both highs and bass channel. Being class A/B it needs to be longer to dissipate the extra heat. If you are a sound quality listener and are not playing full power for long periods of time, I'd go with the 5X II, save a few bucks and get A/B sound. If you want to pound hard without the thermal issues I'd get the ST-5D and the sound should be close. We designed it to be better sounding than other class D amps so it is more expensive to build."
> 
> So the 5X II is considerably cheaper than the 5D for close to the same power. Who knows if someone switched amps between the two if anyone could tell the difference.


I’d question that rep. Calling it a highs amp is not something a rep should say.


----------



## rton20s

SnakeOil said:


> I’d question that rep. Calling it a highs amp is not something a rep should say.


Question all you want. John and Zapco continue to bring some of the best "bang for the buck" amplifiers to market, year after year. And their top tier offerings up up there with the absolute best in (car) audio. Just take a look at the discussion of their products here and on FB groups over the last few years.


----------



## Patriot83

SnakeOil said:


> I’d question that rep. Calling it a highs amp is not something a rep should say.


I'm not sure what his job at zapco is exactly but he answers emails. I listed the quote to show that apparently zapco thinks there is a difference in sound between amplifiers. Of course he went on to say the Z series sounds best of all.


----------



## SnakeOil

rton20s said:


> Question all you want. John and Zapco continue to bring some of the best "bang for the buck" amplifiers to market, year after year. And their top tier offerings up up there with the absolute best in (car) audio. Just take a look at the discussion of their products here and on FB groups over the last few years.


Cool. But doesn’t change the fact that rep has no idea what he’s talking about.


----------



## rton20s

SnakeOil said:


> Cool. But doesn’t change the fact that rep has no idea what he’s talking about.


----------



## mitchell0715

Don't question SnakeOil, he's smarter than all of you ever are and will be. You should bow down to him, fondle his balls, and do everything he tells you to do


----------



## Dhorus

My amps don’t overheat under there, and sound awesome (That’s a high technical term). 


Sent from my iPhone using Tapatalk


----------



## SnakeOil

mitchell0715 said:


> Don't question SnakeOil, he's smarter than all of you ever are and will be. You should bow down to him, fondle his balls, and do everything he tells you to do


The butt hurt is strong in this forum. 
I’m not smart. But I know the technical term is full range not “highs” amp. 
I don’t think people where picking up what I was saying.


----------



## mitchell0715

SnakeOil said:


> The butt hurt is strong in this forum.
> I’m not smart. But I know the technical term is full range not “highs” amp.
> I don’t think people where picking up what I was saying.


It's not just this one time I'm referencing.


----------



## cobb2819

cobb2819 said:


> Stay on topic.


----------



## SnakeOil

Ok. Sorry if I’ve upset you. It’s not my intention.


----------



## rton20s

cobb2819 said:


>


----------



## cobb2819

Dustin,

You're not helping.


----------



## theobjectivist

Any thoughts why the industry isnt turning 100% to class D technology?

If Ds are able to switch fast enough for full range sound, (and theyre smaller, cooler, higher powered and more efficient), im not seeing why top tier amps are still A/B.


I need an ultra compact and efficient design due to my vehicle requirements but it always confuses my as to why the top mosconi, zapco, brax, etc remain stuck on class A and A/B. 


Shouldnt these vendors be one ones bringing us the GaN FET and hypex ultra high end class D designed amps?


----------



## Dhorus

I do believe that at the very top a class A/B can still have that 0,01% better SQ. The advantages, to me, (smaller / Better efficiency / less heating) still make me go D.


----------



## gijoe

theobjectivist said:


> Any thoughts why the industry isnt turning 100% to class D technology?
> 
> If Ds are able to switch fast enough for full range sound, (and theyre smaller, cooler, higher powered and more efficient), im not seeing why top tier amps are still A/B.
> 
> 
> I need an ultra compact and efficient design due to my vehicle requirements but it always confuses my as to why the top mosconi, zapco, brax, etc remain stuck on class A and A/B.
> 
> 
> Shouldnt these vendors be one ones bringing us the GaN FET and hypex ultra high end class D designed amps?


A lot of it has to do with the fact (as you can gather from this thread) that many people still don't believe class D is that good. People wanting high end gear won't buy class D if they are still under the impression that it's inferior. Change scares people, and the high end amp market knows this, they don't want to make all of their amps class D and scare their customers into buying from the competition who are still willing to make A/B amps. 

Besides, Class D hasn't been this good for that long, it will take some time for A/B to completely go away.


----------



## KillerBox

theobjectivist said:


> Any thoughts why the industry isnt turning 100% to class D technology?


In my opinion, some high end manufactures don't like spending money on research and development. 

They will let someone else take the initial research cost hit and then they will come out with their "improved" product.


----------



## Ziggyrama

KillerBox said:


> In my opinion, some high end manufactures don't like spending money on research and development.
> 
> They will let someone else take the initial research cost hit and then they will come out with their "improved" product.


Ding ding ding. Profit margins shrink when you have to make a new product and market it. If something is selling well, there is no need to replace it until they believe the competition will force them to. It is a delicate balance between keeping up and monetization of what you have and what the majority of the market wants.

Sent from my Pixel using Tapatalk


----------



## PPI_GUY

Ziggyrama said:


> Ding ding ding. *Profit margins shrink when you have to make a new product and market it. * If something is selling well, there is no need to replace it until they believe the competition will force them to. It is a delicate balance between keeping up and monetization of what you have and what the majority of the market wants.


This is the point I was making earlier about JL Audio. The cost to R&D a proprietary design is always reflected in higher MSRP. 
People can choose to see it as "priced too high" or an investment in a unique product. That's why cookie-cutter amps are so abundant. It's easy and cheaper to just grab an existing board and stuff it into a new heat sink. 
Same is true for class a/b amps. No real changes in their design since SMD became an industry standard. They're cheap and a proven design. But, the trade-off will always be inefficiency, size and heat.


----------



## SnakeOil

Proprietary don’t mean high price. All mainstream amps are proprietary. Even some “underground’s” are. They are not priced $1 plus a watt.


----------



## rob feature

SnakeOil said:


> Proprietary don’t mean high price. All mainstream amps are proprietary. Even some “underground’s” are. They are not priced $1 plus a watt.


Hard to argue that an amp uses proprietary designs when all that sets it apart from other amps is the case. Something like RIPS in some JL amps - that's what I'd consider closer to proprietary. Very few if any other amps can do that.

Still a curious choice of words though. Proprietary, at least in my vocabulary, means something unique that the manufacturer created that no other manufacturer uses - such as Alpine's amp connectors.


----------



## SnakeOil

Kicker, JBL, Alpine, RF, etc. all one off designs.


----------



## Ziggyrama

rob feature said:


> Hard to argue that an amp uses proprietary designs when all that sets it apart from other amps is the case. Something like RIPS in some JL amps - that's what I'd consider closer to proprietary. Very few if any other amps can do that.
> 
> Still a curious choice of words though. Proprietary, at least in my vocabulary, means something unique that the manufacturer created that no other manufacturer uses - such as Alpine's amp connectors.


Indeed. Meaning of proprietary means unique to the manufacturer or having exclusive rights to a design.

That being said, word of caution, just because you don't see something doesn't mean it isn't there. That may mean the use of specific elements in the design or the processes that are employed to create the product like manufacturing or quality control. There is a lot that goes into testing when something goes into a car. Company like JL that is considered more of a premium consumer brand has a stake in good quality control so they probably spend more on assuring that their amps perform well and continue to do so in extreme situations. That costs . It is easy to trivialize this but the truth is there a lot more to making these amps than you think.

I work for a medium sized global audio company which also has an automotive division. I have conversed with the engineering director about these things and I have walked through a manufacturing plant that makes our cones. Believe me, there is more going on than you think, especially today when software is a major component.

Sent from my Pixel using Tapatalk


----------



## rob feature

SnakeOil said:


> Kicker, JBL, Alpine, RF, etc. all one off designs.


That may be the case, but cross-branding of amp boards is nothing new.


----------



## I800C0LLECT

JL does have higher prices than most consumers want to accept. I've always appreciated that their products do withstand a lot of abuse and are still thoughtful. i.e. The differential rear fill is built into their 500/5. That's pretty neat. Finding their old designs all over Craigslist is a testament to quality imo. It's kind of like Crutchfield vs. WoofersEtc. 

Sent from my SM-G955U using Tapatalk


----------



## SnakeOil

Woofers etc has a way better selection then crutchfield. I’m not sure how you meant that part.


----------



## rob feature

SnakeOil said:


> Woofers etc has a way better selection then crutchfield. I’m not sure how you meant that part.




Even if they do have a better selection (I'm not convinced), one of these companies has a tremendous reputation while the other's is pretty spotty.


----------



## wizzi001

SnakeOil said:


> Woofers etc has a way better selection then crutchfield. I’m not sure how you meant that part.


Everything Crutchfield sells has a factory warranty.


----------



## SnakeOil

I’m sure WE also has a warrenty. When it comes to electronics most faults are the user, warranties won’t cover that anyway. 

This is like any other topic, once ones mind is made up it’s made up. No matter who says what.


----------



## wizzi001

SnakeOil said:


> I’m sure WE also has a warrenty. When it comes to electronics most faults are the user, warranties won’t cover that anyway.
> 
> This is like any other topic, once ones mind is made up it’s made up. No matter who says what.


Woofersetc has a lot of grey market items. So, if they have a warranty it is not from the factory. The Alpine PDX-M6 I bought from them had most of the paperwork removed and the upc was covered up by a sticker. So, please stop being ignorant since I have experience with Woofersetc.


----------



## SnakeOil

But if it broke would they replace it? That’s the question. 
I’m sure thousands more also have experience, good or bad. 
I’m sure some have had bad experience with crutchfield also.


----------



## Patriot83

wizzi001 said:


> Woofersetc has a lot of grey market items. So, if they have a warranty it is not from the factory. The Alpine PDX-M6 I bought from them had most of the paperwork removed and the upc was covered up by a sticker. So, please stop being ignorant since I have experience with Woofersetc.



Wizzi, did you have problems with that amp? 

As for woofers etc, I saw a scathing review on amazon about them. Pretty sure it was about a zapco amp that was doa. Guy sent it back to woofers etc. They told him they were sending it to get repaired by zapco. Kept giving him the runaround saying they called zapco and was told it would be repaired soon. The guy called zapco and was told woofers etc isn't affiliated with them whatsoever and not to buy from them and that they've never talked to him. After a few months and many inquiries the guy was just out a amplifier and his money. Sounded like a complete nightmare....woofers etc sells thousands of things and I'm sure many people have been satisfied with them but I'm not taking the chance.


----------



## SnakeOil

According to atrend, woofersect is a authorized Zapco dealer. So somebody is lying.


----------



## I800C0LLECT

Maybe they're working on their business but they used to be fairly awful. They would list items they didn't have in stock. So you could find any car audio item you ever dreamed. When the order couldn't be fulfilled, offer you something that only THEY KNEW they had in lieu of your original purchase. Pretty common complaint in these forums and others. 

Sent from my SM-G955U using Tapatalk


----------



## Patriot83

SnakeOil said:


> According to atrend, woofersect is a authorized Zapco dealer. So somebody is lying.



I tried finding the review again but kinda busy right now. He listed very specific details, names and days/times of who he spoke to and everything. Seemed like a pretty honest review. I never checked to see if woofers etc was a authorized retailer for zapco. This was last year sometime


----------



## dsw1204

Patriot83 said:


> Wizzi, did you have problems with that amp?
> 
> As for woofers etc, I saw a scathing review on amazon about them. Pretty sure it was about a zapco amp that was doa. Guy sent it back to woofers etc. They told him they were sending it to get repaired by zapco. Kept giving him the runaround saying they called zapco and was told it would be repaired soon. The guy called zapco and was told woofers etc isn't affiliated with them whatsoever and not to buy from them and that they've never talked to him. After a few months and many inquiries the guy was just out a amplifier and his money. Sounded like a complete nightmare....woofers etc sells thousands of things and I'm sure many people have been satisfied with them but I'm not taking the chance.


I called Atrend a little over a year ago asking for a list of online retailers. They gave me a list and Woofers, etc. was on there. I know some people have had issues with Woofers, but them not being a Zapco authorized dealer shouldn't be one of them.


----------



## PPI_GUY

I had a recent interaction with WoofersEtc. thru customer support and found them to be pretty rude. In fact, the tone of their response caused me to purchase elsewhere.

As far as JL Audio goes, their products speak for themselves. From components, to subwoofers to amplifiers, they sell excellent products...and lots of it. Never heard anyone say they felt JL gear was inferior quality.


----------



## SnakeOil

The RD is on my short list of amps. Right now it’s those or the Zapco ST-4 and mono. 
I can get more power on the sub stage with the Zapco combo. 
The RD would just be the 5 channel. I’m sure it will be plenty.


----------



## msmith

DPGstereo said:


> Usually guys in class D camp also believe active is superior to passive...


I would love to hear you defend passive vs. active, but that should really be the start of a new thread.


----------



## msmith

Patriot83 said:


> Yeah it was a very weird set up in that jeep. I know there's a lot of love on here for the xd amps but you know when you hear something and you expect more, you feel disappointed. Highly doubt it was the speakers. I'll try to keep an open mind till I hear another xd set up


If a speaker's colorations coincide with an acoustic issue in the vehicle, and reinforce one another, that is much more likely audible than what amp you are using. 

Things that contribute to the sound you hear in a vehicle...

1) the vehicle's acoustics
2) the speakers
3) the installation of the speakers
4) the tuning of the system













78) The amplifier's sonic qualities



80) Interconnect cables (assuming there is no noise)


89) Speaker cables


----------



## msmith

SnakeOil said:


> The XDs and HDs and Slash amps don’t seem to have much in the way of value.
> That has nothing to do with how they sound.
> They are not small or big on power compared to whats out there these days. No fancy networks.
> The RDs seem ok for their price point but it’s not that ok.
> Maybe I’m missing something, even in the early 2000s if you where not a JL fanboy there where better equipment to be had.


If they lacked value in the general sense, they wouldn't sell. The XD is an incredibly successful amplifier line. So is HD... Slash has been selling for almost 20 years now. 

If you don't see value in them, that's entirely fair. Make your own judgments based on your needs and wants.


----------



## Patriot83

msmith said:


> If they lacked value in the general sense, they wouldn't sell. The XD is an incredibly successful amplifier line. So is HD... Slash has been selling for almost 20 years now.
> 
> If you don't see value in them, that's entirely fair. Make your own judgments based on your needs and wants.



The RD amps have almost identical specs to the XD's other than the slight power increase of the XD. The RD amps have gotten some good professional reviews also. So what is the main advantage of XD over RD?


----------



## msmith

Patriot83 said:


> The RD amps have almost identical specs to the XD's other than the slight power increase of the XD. The RD amps have gotten some good professional reviews also. So what is the main advantage of XD over RD?


The core amplifier sections are essentially the same design, with some differences in component selection and layout. Power supply and input sections are a little simpler in RD. 

There are some feature differences as well. XD has more flexible signal processing.

XD is more compact.

And there are many more models in the XD line, too.


----------



## Patriot83

msmith said:


> The core amplifier sections are essentially the same design, with some differences in component selection and layout. Power supply and input sections are a little simpler in RD.
> 
> There are some feature differences as well. XD has more flexible signal processing.
> 
> XD is more compact.
> 
> And there are many more models in the XD line, too.



Thanks for educating us on JL products. Always good to hear from a top industry official


----------



## PPI_GUY

msmith said:


> The core amplifier sections are essentially the same design, with some differences in component selection and layout. Power supply and input sections are a little simpler in RD.
> 
> There are some feature differences as well. XD has more flexible signal processing.
> 
> XD is more compact.
> 
> And there are many more models in the XD line, too.


Manville, are there any plans to add the RD's clipping indicators to the XD line in the future or would that further blur the line? 
Just seems that is a feature that is becoming more commonly offered as well as a useful tool to help DIY'ers protect their investment while installing. 
Also a feature you'd expect to see on the next "step up" in the JL lineup.


----------



## DPGstereo

msmith said:


> I would love to hear you defend passive vs. active, but that should really be the start of a new thread.




I think we live pretty close to one another. Maybe you should listen to my truck some time.


----------



## DPGstereo

msmith said:


> I would love to hear you defend passive vs. active, but that should really be the start of a new thread.




I also have a Jeep with your amps. HD600/4 and HD1200/1.
Both with 8to12 Aerospace dsp's.

Good amps.
But a different animal than my truck?

But, is it really fair to compare a $800 amp to a $3,500 amp? One being fairly compact and the other with no limitations? 
A different thing for a different customer. I am a fan of JL Audio. But, it is what it is. Bang for the buck...i'd say hard to beat.


----------



## msmith

DPGstereo said:


> I think we live pretty close to one another. Maybe you should listen to my truck some time.




Sure. I’m in Broward County. You can listen to my car, as well. Fully active, with Class D amplifiers. 

I’ve done lots of passive setups over the years, including some winning competition cars. I know they can work very well, but I will still go active whenever possible/practical.


----------



## SnakeOil

msmith said:


> Sure. I’m in Broward County. You can listen to my car, as well. Fully active, with Class D amplifiers.
> 
> I’ve done lots of passive setups over the years, including some winning competition cars. I know they can work very well, but I will still go active whenever possible/practical.


Can you say anything about the upcoming amp?


----------



## Patrick Bateman

msmith said:


> If they lacked value in the general sense, they wouldn't sell. The XD is an incredibly successful amplifier line. So is HD... Slash has been selling for almost 20 years now.
> 
> If you don't see value in them, that's entirely fair. Make your own judgments based on your needs and wants.


Very cool to see you posting here.


----------



## DPGstereo

msmith said:


> Sure. I’m in Broward County. You can listen to my car, as well. Fully active, with Class D amplifiers.
> 
> I’ve done lots of passive setups over the years, including some winning competition cars. I know they can work very well, but I will still go active whenever possible/practical.



In all honesty, I'd really like to meet you sometime and give your vehicle a listen.
Sounds like you know what you're talking about.


----------



## rob feature

msmith said:


> The core amplifier sections are essentially the same design, with some differences in component selection and layout. Power supply and input sections are a little simpler in RD.
> 
> There are some feature differences as well. XD has more flexible signal processing.
> 
> XD is more compact.
> 
> And there are many more models in the XD line, too.


Thanks for that! I'd been wondering what the differences were aside from looks. Didn't realize they were that different. 

Any chance you can expand a little on what a simpler power supply and inputs mean in the real world? To me simpler sounds ideal.


----------



## I800C0LLECT

DPGstereo said:


> In all honesty, I'd really like to meet you sometime and give your vehicle a listen.
> Sounds like you know what you're talking about.


He definitely knows! He's good people too. A very good ambassador to the hobby and well respected in the industry

http://www.jlaudio.com/header/Company/JL+Audio+History/1975-1991/JL+Audio+History:+1975-1991/719800


Sent from my SM-G955U using Tapatalk


----------



## msmith

SnakeOil said:


> Can you say anything about the upcoming amp?




Not just yet. This weekend we will debut them at an industry event in Indianapolis. I can share some info after that.


----------



## PPI_GUY

msmith said:


> Not just yet. This weekend we will debut them at an industry event in Indianapolis. I can share some info after that.


I'm very interested. Saw the news release yesterday on 12 Volt News. Very hush-hush and super secret!


----------



## KillerBox

DPGstereo said:


> In all honesty, I'd really like to meet you sometime and give your vehicle a listen.
> Sounds like you know what you're talking about.


Manville has been doing this for a very long time! This video is from 1989 https://www.youtube.com/watch?v=5qV27hqtKFQ


----------



## PPI_GUY

msmith said:


> Not just yet. This weekend we will debut them at an industry event in Indianapolis. I can share some info after that.


I'm wondering JL's newest toy will incorporate GaN FET technology as part of the topology? It's definitely coming and I wouldn't be surprised to see JL out front with it.


----------



## AAAAAAA

I think the big news with the upcoming JL amps are unboard DSP no? That's what everyone is doing now.


----------



## PPI_GUY

AAAAAAA said:


> I think the big news with the upcoming JL amps are unboard DSP no? That's what everyone is doing now.


You may be (and probably are) right. I'm just kinda excited to hear a class D amplifier that potentially could rival class A with a virtually non-existent noise floor. I might be jumping the gun by a few years though. :laugh:


----------



## thehatedguy

It's not a GaN amp.

I've seen the new amps though,


----------



## SnakeOil

GaN in a JL amp or any big box amp won’t happen.


----------



## theobjectivist

I agree with whats mentioned above that a lot of vendors are integrating the DSP and it's a good guess as to what JL has planned. 

i'd kill for a truly next gen 6 x 150 watt amp with a class D design. GaN would be amazing. What a shame JL isnt taking that path. (how can a company like soundigital pull it off?)




Between waiting for new amp designs, and zapco actually finishing their new DSP, i feel as if im waiting for the impossible. sighh


----------



## SnakeOil

theobjectivist said:


> I agree with whats mentioned above that a lot of vendors are integrating the DSP and it's a good guess as to what JL has planned.
> 
> i'd kill for a truly next gen 6 x 150 watt amp with a class D design. GaN would be amazing. What a shame JL isnt taking that path. (how can a company like soundigital pull it off?)
> 
> 
> 
> 
> Between waiting for new amp designs, and zapco actually finishing their new DSP, i feel as if im waiting for the impossible. sighh


What do you mean by “a company like soundigital”?


----------



## theobjectivist

SnakeOil said:


> What do you mean by “a company like soundigital”?


brazilian amp company soundigital somehow actually made a GaN amp

It was tested as one of the best sounding mobile amps around, even besting the ultra boutique brands. I think the report was by a guy named matt hall?


Anyways, as incredible as it was, it was only two channels and they apparently stopped making it. (the model was called soundigital gan 300.2d)

Ive heard that theyre going to fire up again with multi channel versions but at this stage it seems like a super long shot


----------



## SnakeOil

Brother SD has been world class for a long time. They just where not big in the US unless you saw them in a record breaking SPL rig. 
I’m sure they sound good as any other good amp.


----------



## bnae38

Most of the reason I've trolled this thread.. getting impatient waiting for GAN to hit mainstream . Would think it is the next logical next step in high end amplifier technology.. 

Ultra-efficient, stupid low xo distortion, etc.. love what I read but.... cmonnn


----------



## PPI_GUY

bnae38 said:


> Most of the reason I've trolled this thread.. getting impatient waiting for GAN to hit mainstream . Would think it is the next logical next step in high end amplifier technology..
> 
> Ultra-efficient, stupid low xo distortion, etc.. love what I read but.... cmonnn


I'm with you on being impatient for this technology to make it to the mainstream. I see no reason why JL, Alpine, Sony or some other flagship brand wouldn't jump in when the parts to assemble are readily available. 
IMO it's the next big step. Wonder if (as usual) we'll have to wait until the home audio market has been well saturated with devices using GaN FET technology before it will finally make it to mobile audio?


----------



## PPI_GUY

SnakeOil said:


> GaN in a JL amp or any *big box amp *won’t happen.


No idea what you mean by that. Cost I guess? As with everything the cost to manufacture and implement new tech always follows a curve. Just a few years ago plasma TV's were all the rage and now LED's are almost so cheap they are borderline disposable. Within 10 years I suspect GaN will be the standard for both home and mobile audio. Especially in the audiophile market.


----------



## GEM592

PPI_GUY said:


> No idea what you mean by that. Cost I guess? As with everything the cost to manufacture and implement new tech always follows a curve. Just a few years ago plasma TV's were all the rage and now LED's are almost so cheap they are borderline disposable. Within 10 years I suspect GaN will be the standard for both home and mobile audio. Especially in the audiophile market.


I could be wrong but I tend to agree ... I don't see JL closing the loop on GaN tech amps for car audio. They will step in and try to saturate the market after somebody else paid the up-front costs.


----------



## Ziggyrama

GEM592 said:


> I could be wrong but I tend to agree ... I don't see JL closing the loop on GaN tech amps for car audio. They will step in and try to saturate the market after somebody else paid the up-front costs.


Big problem is that car audio market is shrinking overall, at least in US and Europe which means it is harder to invest capital for the future. The big names know this therefore are gun shy on major investments on new products. It may seem simple on the surface to build a new amp using new parts but see my previous post on all the things involved that they need to do to push out a new product. I see some big names shrinking or even going away in the next 10 years.

Sent from my Pixel using Tapatalk


----------



## SnakeOil

PPI_GUY said:


> No idea what you mean by that. Cost I guess? As with everything the cost to manufacture and implement new tech always follows a curve. Just a few years ago plasma TV's were all the rage and now LED's are almost so cheap they are borderline disposable. Within 10 years I suspect GaN will be the standard for both home and mobile audio. Especially in the audiophile market.


Look at neo motors. You see a ton of smaller brands using them but very few big box using them. The only thing that matters to big boxes are profit. Better materials mean less profit.


----------



## bnae38

Unless... The retail cost is more


----------



## SnakeOil

Just look at JLs new amp. It’s a DSP amp, they are marketing like they are leading the way. DSP amps have been around for 9 years or more. 
Don’t be fooled


----------



## thehatedguy

Here's my stash of SD GaN amps.


----------



## Grinder

thehatedguy said:


> Here's my stash of SD GaN amps.


Only eleven, er... I mean, only 285 days 'til Xmas


----------



## thehatedguy

I may have cornered the market in what is/was left new in stock.


----------



## Grinder

thehatedguy said:


> I may have cornered the market in what is/was left new in stock.


Good call!


----------



## Blu

thehatedguy said:


> I may have cornered the market in what is/was left new in stock.


Oh my...

One to each driver and then some?


----------



## mitchell0715

thehatedguy said:


> I may have cornered the market in what is/was left new in stock.


christ man what was your reason for so many of them?! lol

i can understand doing it to make profit but the other part me is kinda upset if thats why


----------



## GreatLaBroski

Why has there not been an open-source car-audio amplifier line created yet? I'd think that would be a great way to get these newer designs out into enthusiasts hands (like GaN). Maybe I'm just thinking like an engineer.


----------



## Ziggyrama

GreatLaBroski said:


> Why has there not been an open-source car-audio amplifier line created yet? I'd think that would be a great way to get these newer designs out into enthusiasts hands (like GaN). Maybe I'm just thinking like an engineer.


What source would you open? I don't know for sure but I don't believe there is much micro code running on these amps. Ones with DSP features are an exception.

Sent from my Pixel using Tapatalk


----------



## SSSnake

> What source would you open? I don't know for sure but I don't believe there is much micro code running on these amps. Ones with DSP features are an exception.


Open source doesn't only pertain to code there are open source designs as well (however code is the most common). IMO there isn't a ton of mystery in amplification stage design but a little more mystery in the power supply. Besides even with an open source the cost for the board and other parts in small quantities will eat you alive. Also packaging efficiency. Most folks aren't going to do well soldering surface mount parts and getting access to a wave soldering device is usually out of most peoples grasp. So you are likely to end up with a larger, less dependable, more expensive amp. Not too strong on the selling points.


----------



## Bnlcmbcar

How about something that is sized to be flexible enough to accept interchangeable components.. like the approach of new Zapco V DSP thats on the way..

Where one could choose
-Regulated vs unregulated power supply
-something like swappable Hypex modules for different wattages that are desired
-Maybe some sort of modular casing that is connectable to add more channels if desired

One can dream a little.


----------



## GreatLaBroski

Ziggyrama said:


> What source would you open? I don't know for sure but I don't believe there is much micro code running on these amps. Ones with DSP features are an exception.
> 
> Sent from my Pixel using Tapatalk


I mean the design / gerber files, plus firmware. A true open-source audiophile grade amplifier that takes advantage of the latest and greatest.



SSSnake said:


> Open source doesn't only pertain to code there are open source designs as well (however code is the most common). IMO there isn't a ton of mystery in amplification stage design but a little more mystery in the power supply. Besides even with an open source the cost for the board and other parts in small quantities will eat you alive. Also packaging efficiency. Most folks aren't going to do well soldering surface mount parts and getting access to a wave soldering device is usually out of most peoples grasp. So you are likely to end up with a larger, less dependable, more expensive amp. Not too strong on the selling points.


I’m not 100% sure about the points you’re making here. PCBway would be one source of custom PCBs out of China which would provide you with 10” x 6” boards for $50 for a quantity of 10 boards ($5/ea). GaN amps seem much smaller than their less efficient counterparts. Components aren’t super expensive from digikey, although high-power GaN components look very expensive at first glance. I’d have to see the actual components used in the few car audio GaN amps to really write that off first though.

Id expect the body to be extruded aluminum with some sort of an aluminum body baseplate. So it’d have a cool older-school look.

Soldermasks aren’t too hard to get made too, if you have the files. As a matter of fact, a lot of the reliability issues stem from bad solder joints and lead-free solder not performing as well in shock-prone environments, so having access to leaded solder would be a boon.

But anyways I guess there would have to be an upswell of educated enthusiasts who wanted to put the time into designing and sourcing price-efficient components into a price-efficient diy design that could be improved by the community. This has been done in other communities like the electric skateboard community with the open source VESC. I figured maybe there was some community like the ham-radio community in car audio that would be DIY’ers at this stuff.

But that’s my answer I guess: someone would need to do it and others would need to support the project for it to be worthwhile.


----------



## AAAAAAA

The only modularity that I would like it a way to "snap" amplifiers form the same line together as to share power and ground and RCA's.
Finally, a way to SNAP on a DSP module. Anything else is just too much IMO..


----------



## KillerBox

AAAAAAA said:


> The only modularity that I would like it a way to "snap" amplifiers form the same line together as to share power and ground and RCA's.
> Finally, a way to SNAP on a DSP module. Anything else is just too much IMO..


Something like an old school Canton mainframe amplifiers? Back in the late 1980s, I wanted to try one so bad!

https://www.ebay.com/itm/NEW-Canton...986011?hash=item282e919a5b:g:3pkAAOSw2xRYg8Yp


----------



## Bnlcmbcar

Bnlcmbcar said:


> How about something that is sized to be flexible enough to accept interchangeable components.. like the approach of new Zapco V DSP thats on the way..
> 
> Where one could choose
> -Regulated vs unregulated power supply
> -something like swappable Hypex modules for different wattages that are desired
> -Maybe some sort of modular casing that is connectable to add more channels if desired
> 
> One can dream a little.


Maybe Bill at Biketronics can come up with something if someone is willing to hand him a large investment. Envision those current mini bike amps but in normal sized amp enclosures and a stout PCB board that is able to accept some of the individual components that make up the amp via slots/ports to eliminate soldering.

It would require some amazing engineering, hence high capital costs, which would probably lead whoever figures it out to make it proprietary technology and the open source nature dies... but hey at least different user options could be available on a single platform.

(I know very little about manufacturing power amplifiers. Just daydreaming a little)


----------



## SSSnake

> I’m not 100% sure about the points you’re making here. PCBway would be one source of custom PCBs out of China which would provide you with 10” x 6” boards for $50 for a quantity of 10 boards ($5/ea).


I guess I am showing my age. The last time I had a custom board made, which as quite a while back, it was 10 x that for a 2 layer. Of course it was also done local not in China. Maybe this global economy thing ain't so bad after all.


----------



## SSSnake

Back in the day when AB was king I wanted to build an amp on a thick film hybrid substrate so that I could get the tolerances tighter and hopefully minimize thermal drift. The pricing, even with access to s screen printer and oven, was way out there.


----------



## GreatLaBroski

SSSnake said:


> I guess I am showing my age. The last time I had a custom board made, which as quite a while back, it was 10 x that for a 2 layer. Of course it was also done local not in China. Maybe this global economy thing ain't so bad after all.


Yeah it used to be SUPER expensive and take 10 weeks to get a custom PCB. Now we're at a point where they'll ship in a week or less and cost next to nothing. It's kind of fueled the resurgence of hardware startups over the last few years. I'd love to see some community amp designs start to pop up and be tested and refined.


----------



## Holmz

GreatLaBroski said:


> ...
> A true open-source audiophile grade amplifier that takes advantage of the latest and greatest.
> ...


The "Latest" part I get.

There are already lots of amplifiers available. What would another do better?

Most of magic seems to happen in the switching controller, which makes it act linear and any feedback to make the output impedance low.


----------



## thehatedguy

In class D, the faster you switch with the lowest amount of dead time, the better your result would be.


----------



## thehatedguy

In theory, if you could switch fast enough with little dead time, you could make a pure sine wave meaning looking like class A output without the constant current draw.

That's where class D is heading...if you can switch fast enough.


----------



## Holmz

thehatedguy said:


> In class D, the faster you switch with the lowest amount of dead time, the better your result would be.


That is certainly true for open loop performance, but there would need to be some closed loop feedback to address back EMF.

There is an inductor and a capacitor on the output stage, forming a low pass filter. One could also have a notch filter at the switching frequency. Who knows? Maybe they have those as well, as it would cheap and easy to do.

So I am back to believing that the magic must be in the switching controller.


----------



## stickpony

gijoe said:


> There isn't a difference. Class D is here to stay, and I'm sure most manufactures will stop designing AB altogether before long. Class D amps are switching amplifiers, now that those switching frequencies are as high as they are class D can play full range as cleanly as any AB amp, while using a lot less energy.
> 
> If you are trying to tune your system by swapping amps you will constantly be hearing things that either aren't there, or that could easily be changed with a basic EQ. As some have already mentioned, if the system sounds "sterile" or "lifeless" or (insert vaguely defined audiophile jargon here) the amp is the last place to look.


There is a technical reason why class D might sound more 'sterile', i dont know what it is, but i remember reading about it in a home theater magazine. im convinced that sterile means 'clean', and that the audiophile 'warmth' attributed to class A or class A/B designs probably has a lot to do with certain components 'coloring' the sound, which makes me think that if you play with EQ, you can accomplish mostly the same thing on a class D amp, so i am going to have to agree with you here.

ultimately, i think it just comes down to the quality of the components. any sound system is only as good as its weakest link


----------



## bnae38

stickpony said:


> There is a technical reason why class D might sound more 'sterile', i dont know what it is, but i remember reading about it in a home theater magazine. im convinced that sterile means 'clean', and that the audiophile 'warmth' attributed to class A or class A/B designs probably has a lot to do with certain components 'coloring' the sound, which makes me think that if you play with EQ, you can accomplish mostly the same thing on a class D amp, so i am going to have to agree with you here.
> 
> ultimately, i think it just comes down to the quality of the components. any sound system is only as good as its weakest link



Agree except for part about eq'ing a class D to match the sound characteristics of a different class amp.

Eq wont alter even or odd (or both) order distortion. Only tonality.


----------



## Holmz

stickpony said:


> There is a technical reason why class D might sound more 'sterile', i dont know what it is, but i remember reading about it in a home theater magazine. im convinced that sterile means 'clean', and that the audiophile 'warmth' attributed to class A or class A/B designs probably has a lot to do with certain components 'coloring' the sound, which makes me think that if you play with EQ, you can accomplish mostly the same thing on a class D amp, so i am going to have to agree with you here.
> 
> ultimately, i think it just comes down to the quality of the components. any sound system is only as good as its weakest link


Many amplifiers have astonishingly low THD+Noise values. I doubt one could tell much without an oscilloscope when an amp is operated correctly.

What makes class-A and AB different is the sound when driven into clipping. Running separate amplifiers for each speaker removes a major source of tweeter woe that exists with a passive cross over and overdriven system.

The fact that there are great systems in class-A and AB means that they can work well. The fact that there are also some worldclass systems running Class D means that they also work well.

It is sort of a fallacy to thing that class-D is "the latest and greatest", unless efficiency is - contributor to "greatness".
That said, it seems worthwhile to consider class-D for woofers and subs, even if one has class A snobyness tendencies. Or... really consider class-D if they need to focus minimising overall current draw.

It is basically hard to argue that an amp design with <0.001% THD+N is not pretty much automatically in the "great" category. (One is not hearing the amp as the THD+N goes to 0%.)


----------



## 112db

thehatedguy said:


> It's not a GaN amp.
> 
> I've seen the new amps though,


Is there an official release or post somewhere?


----------



## stickpony

bnae38 said:


> Agree except for part about eq'ing a class D to match the sound characteristics of a different class amp.
> 
> Eq wont alter even or odd (or both) order distortion. Only tonality.


from what ive read, all solid state amps are odd order , and tubes are even order?


----------



## Holmz

stickpony said:


> from what ive read, all solid state amps are odd order , and tubes are even order?


Is that all the time? Or when they are driven into clipping?


----------



## bnae38

Its all the time, typical crossover distortion I see on the dscope with an amp under load is both odd and even fwiw.


----------



## bnae38

Class ab example from audison lrx2.150 w/ 4ohm load, fft shows typical crossover distortion under load. Less than .1% thdn on that fft plot. Not as awful as it looks.. though kind of disappointing tbh..

Red line is thdn vs power plot.


----------



## PPI_GUY

SnakeOil said:


> Just look at JLs new amp. It’s a DSP amp, they are marketing like they are leading the way. DSP amps have been around for 9 years or more.
> Don’t be fooled


I've not fully read up on the new XVi amps but apparently they offer some features and options that come with the built-in DSP's that are new, next level kind of stuff. I doubt very seriously if JL or any other manufacturer would repackage a DSP from 9 years back. 

Also, I believe that investing heavily in R&D (like JL does) allows them to offer unique features on higher quality gear. The absolute best available? Debatable and largely dependent on your needs as well as budget. Might also depend on your wants. To just 'get by' or to believe in the product you're using.


----------



## Jscoyne2

Honestly it just sounds to me that we have enough home audio technology around and its been long enough that were gonna see some next level dsp capabilities in CA world. Im excited 

Sent from my SGH-M919 using Tapatalk


----------



## Holmz

bnae38 said:


> Class ab example from audison lrx2.150 w/ 4ohm load, fft shows typical crossover distortion under load. Less than .1% thdn on that fft plot. Not as awful as it looks.. though kind of disappointing tbh..
> 
> Red line is thdn vs power plot.


I guess the next question is "what does under load" mean in watts? Or in %-clipping? ... assuming that was a sinewave, then even RMS volts works?

Some people swear by amps like the Phass Class-A, and the old McIntosh Class-AB gear at 50W/channel. But it is easier to drive woofers into distortion as there is more voltage as the frequency goes lower... (Hence class D could easily coexist)
Or do all amps really have 0.1% THD+N, when driven? Even the ones that claim 0.001% at full RMS wattage?


----------



## thehatedguy

That's not true at all.



stickpony said:


> from what ive read, all solid state amps are odd order , and tubes are even order?


----------



## bnae38

Holmz said:


> I guess the next question is "what does under load" mean in watts? Or in %-clipping? ... assuming that was a sinewave, then even RMS volts works?
> 
> Some people swear by amps like the Phass Class-A, and the old McIntosh Class-AB gear at 50W/channel. But it is easier to drive woofers into distortion as there is more voltage as the frequency goes lower... (Hence class D could easily coexist)
> Or do all amps really have 0.1% THD+N, when driven? Even the ones that claim 0.001% at full RMS wattage?



Tbh, in depth measurement of amplifiers is somewhat new to me; but using the Dscope is not.

I'm using a bank of non-inductive resistors as the load. Of course non-inductive is nearly non-inductive.. Not entirely. And then, that's obviously not a great representation of a speaker either.. It's the fairly typical benchmark nonetheless.. 

The power for that portion of the graph is done mathematically from the voltage measured, you enter the resistance of the load into the program and it will plot accordingly. 

The interesting thing is the large difference between measuring an amplifier loaded and unloaded, the results are drastically different. I spent some real time looking into that and really doubting my process, but it seems the results are typical crossover distortion for many amplifiers under load.

Here is the same measurements with no load.










Fwiw the fft plots posted are at about 6w. 




Playing around with bias alters and improves the crossover distortion if turned up, but of course we cant just blindly crank that up..


----------



## Holmz

Jscoyne2 said:


> Honestly it just sounds to me that we have enough home audio technology around and its been long enough that were gonna see some next level dsp capabilities in CA world. Im excited


This has nothing to do with the Class-D topic, but...:
1) What would "next level DSP" be?
2) What features would it have and how would it be different from existing DSPs?

The only things I can think of are:
- FIR filters
- DIRAC type (i.e. better impulse response)

However most people say that those are not needed... and there are existing products that have those features.


----------



## mitchell0715

So the new Taramps Bass 12k apparently uses GaN fets. I'd imagine the Bass 15k does too but I'm not sure


----------



## rton20s

In terms of modular amp design it has been brought up many times here in DIYMA (as well as other sites). I don't know that we've actually seen much of it in production though. 

One of the last threads I recall was started by TooStubborn2Fail back when he was starting to work with his father on a new amplifier design. Envisionelec (aka Aaron Hammett) even posted about a design he had developed and linked to a sketchup model video that looked like a 6 slot toaster with a bunch of pop tarts. 

http://www.diymobileaudio.com/forum/technical-advanced-car-audio-discussion/128855-building-amp-scratch-dsp-need-input.html


On another note...

I do like what I was seeing in the new JL VXI amplifiers. Cool stuff. I played around with the iPad app yesterday and it was pretty slick. Very full featured, and it seems like they will be great for factory integration. Fine level of adjustment along with shelving and all pass filters are nice features. It would be cool to see some additional control over how the DRC operates (shelf filter for the subwoofer level). 

I was slightly disappointed in the fact that the power numbers they were quoting at Knowledgefest were for 2 Ohm (not 4 Ohm) loads. Though, it isn't too surprising. 75 wpc @ 4 Ohms has been the JL standard for quite some time now and should be plenty for most active systems.


----------



## KillerBox

rton20s said:


> I was slightly disappointed in the fact that the power numbers they were quoting at Knowledgefest were for 2 Ohm (not 4 Ohm) loads. Though, it isn't too surprising. 75 wpc @ 4 Ohms has been the JL standard for quite some time now and should be plenty for most active systems.


I am disappointed in the 75 wpc too. Right now I have 150w x 14 & 600w x 2 and wished I had more!

I do like the 8 channel amp though! Big fan on multiple channels without having to fight with a bunch of wiring.

I also haven't gotten a straight answer on if the JL vXI amps are going to have any type of surround sound processing for a 7.1 system. If it doesn't, my 3 or 4 backup JBL MS-8s are prepared to hold out for years for a new DSP that does!


----------



## thehatedguy

They are not going to have any surround processing.


----------



## KillerBox

thehatedguy said:


> They are not going to have any surround processing.


Thanks for the answer! I don't think I will ever understand why most manufactures' refuse to include surround sound processing in their DSPs. 

I had a surround sound processor 30+ years ago and I refuse not to have one now. I am a big fan of ambiance off live recordings.


----------



## Holmz

KillerBox said:


> Thanks for the answer! I don't think I will ever understand why most manufactures' refuse to include surround sound processing in their DSPs.
> 
> I had a surround sound processor 30+ years ago and I refuse not to have one now. I am a big fan of ambiance off live recordings.


Most people probably do not feel the need for surround sound.
Or...
the rest probably do not want to be forced into having to have 16 amplification channels.


----------



## KillerBox

Holmz said:


> Most people probably do not feel the need for surround sound.
> Or...
> the rest probably do not want to be forced into having to have 16 amplification channels.


Easy to do with a couple of 8 channel amps and in my opinion it is so worth it!


----------



## rton20s

Most aren't integrating upmixing due to licensing fees. Many of the DSP chips used in processors available to us today have the capability of doing the upmixing and surround processing. Pay the licensing fee and it is readily available. 

It takes deep pockets and a long time for those licensing fees to pay off. Think about the only manufacturers that have done it to date. Rockford Fosgate (developed the technology), Alpine (deep pockets, long term investment over multiple DSPs), and JBL (Harman, continued development of the technology, deep pockets, long term investment). We'll see what Andy ends up doing with the upmixing processor he has been working on. 

In the mean time, if you have a factory system with a center channel and an OE DSP amp that does the proper upmixing, it is always an option to keep the OE unit in place for the upmixing and feed that signal into your own DSP and amps.


----------



## KillerBox

I know we are getting off subject but, I had one of these in the 1980s & I was hooked. 

It would be pretty bad to buy a state of the art new DSP, class D amps & run a 1980s surround sound processor!

Old School, JIM FOSGATES / GAVOTTE 360 DEGREES DIGITAL SPACE MATRIX fosgate NEW! 

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/173220058124


----------



## AAAAAAA

Can it really be that steep when all the home receivers have it? ...even the cheep ones.



rton20s said:


> Most aren't integrating upmixing due to licensing fees. Many of the DSP chips used in processors available to us today have the capability of doing the upmixing and surround processing. Pay the licensing fee and it is readily available.
> 
> It takes deep pockets and a long time for those licensing fees to pay off. Think about the only manufacturers that have done it to date. Rockford Fosgate (developed the technology), Alpine (deep pockets, long term investment over multiple DSPs), and JBL (Harman, continued development of the technology, deep pockets, long term investment). We'll see what Andy ends up doing with the upmixing processor he has been working on.
> 
> In the mean time, if you have a factory system with a center channel and an OE DSP amp that does the proper upmixing, it is always an option to keep the OE unit in place for the upmixing and feed that signal into your own DSP and amps.


----------



## stickpony

AAAAAAA said:


> Can it really be that steep when all the home receivers have it? ...even the cheep ones.


Agreed! the JBL MS-8 has Logic 7 surround processing built in, and that DSP is relatively cheap compared to most of the decent DSP's on the market


----------



## stickpony

KillerBox said:


> I know we are getting off subject but, I had one of these in the 1980s & I was hooked.
> 
> It would be pretty bad to buy a state of the art new DSP, class D amps & run a 1980s surround sound processor!
> 
> Old School, JIM FOSGATES / GAVOTTE 360 DEGREES DIGITAL SPACE MATRIX fosgate NEW!
> 
> https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/173220058124


that is a really cool piece of gear. now if it could be modified to have digital inputs and outputs, that would REALLY be cool


----------



## Lanson

Here's something fun to think about, regarding patents in the field of surround sound. Most patents have expired in the field. For instance, just last year the Logic7-related patents were approved in 1997 and now, are expired. https://patents.google.com/patent/US6697491 So if someone really wanted to get up on this, NOW would be the time. Just sayin', open-source surround sound algorithms would be really, really nice to have.


----------



## stickpony

fourthmeal said:


> Here's something fun to think about, regarding patents in the field of surround sound. Most patents have expired in the field. For instance, just last year the Logic7-related patents were approved in 1997 and now, are expired. https://patents.google.com/patent/US6697491 So if someone really wanted to get up on this, NOW would be the time. Just sayin', open-source surround sound algorithms would be really, really nice to have.



if you click the drop-down tabs on the right, you can see the patent was modified and then renewed twice... last time in 2009,


----------



## AAAAAAA

stickpony said:


> Agreed! the JBL MS-8 has Logic 7 surround processing built in, and that DSP is relatively cheap compared to most of the decent DSP's on the market


Even crazier in this case, they made their own ... should be much more expensive -in the short term- then paying licensing fees. and ms8 was still affordable, and as far as I know the only product with logic 7 (apparently harmon lost the code for logic 7).

I don't buy that licensing for surround is that bad. Companies in car audio should be thinking about this long and hard, most new cars come with a center....

Also Alpine's processor has always had it (h700,h800) and is pretty decently priced.


----------



## gijoe

Why would companies spend so much time or energy to bring surround sound to a car? There are already such a small group of people that care about DSP in the first place, that spending money to add a gimmick is silly (yes, I called it a gimmick, even differential rear fill is a gimmick, it synthetically creates the ambiance of a room that you're not in, and that was not part of the intended recording). If you want the sound of a live recording, buy the live version, or go to the show, a studio recording is mixed to sound like a studio recording.


----------



## KillerBox

gijoe said:


> If you want the sound of a live recording, buy the live version, or go to the show, a studio recording is mixed to sound like a studio recording.


I have never had a 2.1 system make me get goosebumps but, my 7.1 does from time to time.

https://didyouknowfacts.com/get-goosebumps-listening-music-might-different-kind-brain/

In my opinion, a live recorded album played on a 7.1 surround sound processor is the closet thing that I can find to a live concert.

I think the biggest hurdle is that most people don't want to go through the hassle or expense to install an aftermarket 7.1 system. So aftermarket systems are going to decline because OEM systems will.


----------



## SSSnake

> spending money to add a gimmick is silly (yes, I called it a gimmick, even differential rear fill is a gimmick, it synthetically creates the ambiance of a room that you're not in, and that was not part of the intended recording).


By that same logic we should not listen to recordings in anything other than anechoic chambers. After all the rooms we listen in definitely color the sound. A live room, like we have in a car, adds a ton of ambience/coloration to the sound. This is one of the reasons I believe we will never get truly accurate audio reproduction in a car but we can strive for believable. I believe Andy W's comment was something along the lines of: we won't get to the "you are there" objective but "being somewhere larger than a car" is a pretty good. Paraphrased very heavily as I can't find the quote.


----------



## gijoe

I keep screwing up multi quotes:

"I have never had a 2.1 system make me get goosebumps but, my 7.1 does from time to time.

https://didyouknowfacts.com/get-goos...nt-kind-brain/

In my opinion, a live recorded album played on a 7.1 surround sound processor is the closet thing that I can find to a live concert.

I think the biggest hurdle is that most people don't want to go through the hassle or expense to install an aftermarket 7.1 system. So aftermarket systems are going to decline because OEM systems will."

If the album is recorded in 7.1 that's a completely different thing that synthetically creating those extra channels.

"By that same logic we should not listen to recordings in anything other than anechoic chambers. After all the rooms we listen in definitely color the sound. A live room, like we have in a car, adds a ton of ambience/coloration to the sound. This is one of the reasons I believe we will never get truly accurate audio reproduction in a car but we can strive for believable. I believe Andy W's comment was something along the lines of: we won't get to the "you are there" objective but "being somewhere larger than a car" is a pretty good. Paraphrased very heavily as I can't find the quote."

An album is recorded to be listened to in a real room, or headphones, not to have an artificial room added. The artist never intended for their music to be listened to in an an-echoic chamber, and if they wanted surround sound, they would have added that too.

I'm not saying that cleverly processed rear fill can't sound good, but even if it sounds good, it's still 100% synthetic.


----------



## rton20s

My comments regarding the cost of licensing comes directly from people that I trust "in the industry." Some of those same people are the ones that have said that activating the upmixing/surround processing on their selected DSP chip is "as simple" as paying the licensing fee and then including that capability as a part of their hardware/software development process. If the cost wasn't significant, there is no reason they wouldn't include it as an option in their DSP. If nothing else, it is one more line item for the marketing guys to include in the ad copy/sales sheet.

I don't have time to hunt down all of the links right now, but there are some great articles online about the history of surround sound and upmixing. They talk about the key players (Jim Fosgate being probably the most well known in car audio), and the competition between algorithms at Harman. Most of which, Andy could probably write a huge post on from memory.


----------



## rton20s

Additionally, both Andy and Manville still put up with this place for some reason. It would be interesting to get their take on it. Andy was involved with the development of the MS-8 which included surround/upmixing and Manville might be able to explain why JL chose to go with the matrix they use in their DSPs rather than a surround/upmix algorithm with advanced signal steering.


----------



## Lanson

stickpony said:


> if you click the drop-down tabs on the right, you can see the patent was modified and then renewed twice... last time in 2009,


Patents cannot be renewed. You mean that they came up with a new idea and then patented that?

The ideas become public domain. I do see the list of improvements in the new patents, the improved efficiency, and stuff. But I must tell ya, I'd take an old patent idea (maybe with some ways to tweak the thing manually) over standard 2 channel anyday.


----------



## Lanson

gijoe said:


> Why would companies spend so much time or energy to bring surround sound to a car? There are already such a small group of people that care about DSP in the first place, that spending money to add a gimmick is silly (yes, I called it a gimmick, even differential rear fill is a gimmick, it synthetically creates the ambiance of a room that you're not in, and that was not part of the intended recording). If you want the sound of a live recording, buy the live version, or go to the show, a studio recording is mixed to sound like a studio recording.


To be fair, 2 channel is a gimmick of the original as well.


----------



## Ziggyrama

gijoe said:


> Why would companies spend so much time or energy to bring surround sound to a car? There are already such a small group of people that care about DSP in the first place, that spending money to add a gimmick is silly (yes, I called it a gimmick, even differential rear fill is a gimmick, it synthetically creates the ambiance of a room that you're not in, and that was not part of the intended recording). If you want the sound of a live recording, buy the live version, or go to the show, a studio recording is mixed to sound like a studio recording.


I agree with the economic argument. This is a very small niche market in an already small and currently shrinking market. Most marketing and finance people would not support investment into an area that will likely not pay back.

As far as things like real fill, that is simply a psychoacoustic effect of simulating waves bouncing back at you from rear walls which are at a significant distance from you. It is not a gimmick. That is what you are hearing when you are there. The problem is, that recording is usually not mixed to relfect this, but rather, produced into 2 channel which means live recordings are not a reasonably accurate reproduction either. So, IMHO arguing about accuracy of reproduction is a total crapshoot because just about any form we pick can be picked apart. Ultimately, if a person likes that sound, why do we care if it is wrong or right? It's like arguing about the slopes on your house curve. Is there only 1 curve that is right? We tune to what we find pleasant. Just let it be.

So, to recap, economics aren't looking good for surround setups, but if one wants it and finds it pleasant, I won't say that is "wrong".

Sent from my Pixel using Tapatalk


----------



## Locomotive Tech

Just thinking out loud here, there are alot of OEM vehicles coming with sorround, the "premium" audio options usually come at a fairly significant cost so the manufacturer has some help with the cost of liscensing there. They also build 10k+ of a given vehicle, and add that same audio system to all of the models they build it starts to add up.

I wonder how long it took JBL (or anyone else) to sell 20k aftermarket processors? Ford, GM, etc. can do that in a year


----------



## stickpony

Most high end car audio gear is a niche market, but still plenty big to afford surround processing, IMO

me personally, i can create accurate rear fill speakers in a car with EQ and time delays on those channels, but i cannot seem to create an accurate center channel, with the same tricks, so really the only reason to have surround on a DSP, is for the center channel. 

I have an Audio Control System 90 model 11 that 'recreates' a center channel, but honestly, it isn't that good at recreating an accurate center channel. The JBL MS-8 was much better IMO at recreating the center channel using the Logic 7 processing, but i felt that it brought the clarity and quality of my overall system down a little bit, compared to when i just had the Pioneer P99rs and the audio control. 

Overall, a really great center channel is an allusive thing, almost like a Unicorn. My next step, i'll try and locate an old ESP-3, and see if the center channel processing is any different than the System 90. 

its funny how sometimes, one must look for old legacy gear to add something new to your system


----------



## gijoe

fourthmeal said:


> To be fair, 2 channel is a gimmick of the original as well.


You can't call it a gimmick if it's recorded that way. Stereo is intended that way from the start. It becomes a gimmick when you add fake channels that aren't there.


----------



## gijoe

Ziggyrama said:


> I agree with the economic argument. This is a very small niche market in an already small and currently shrinking market. Most marketing and finance people would not support investment into an area that will likely not pay back.
> 
> As far as things like real fill, that is simply a psychoacoustic effect of simulating waves bouncing back at you from rear walls which are at a significant distance from you. It is not a gimmick. *That is what you are hearing when you are there.* The problem is, that recording is usually not mixed to relfect this, but rather, produced into 2 channel which means live recordings are not a reasonably accurate reproduction either. So, IMHO arguing about accuracy of reproduction is a total crapshoot because just about any form we pick can be picked apart. *Ultimately, if a person likes that sound, why do we care if it is wrong or right?* It's like arguing about the slopes on your house curve. Is there only 1 curve that is right? We tune to what we find pleasant. Just let it be.
> 
> So, to recap, economics aren't looking good for surround setups, but if one wants it and finds it pleasant, I won't say that is "wrong".
> 
> Sent from my Pixel using Tapatalk


That's what we here when we are where? That room that rear fill creates isn't in the recording, and wasn't in the recording studio. The music was most likely recorded in a booth the size of a closet and any sense of space that it has by the time you get the CD was added to it. That was the intention of the artist, by taking that CD that already had a "room" added to it, then making that room bigger with rear fill is a gimmick. 

If they wanted it in the original recording, they could have added it. 


It doesn't bother me that people like it, and if you'd read my original post on the topic you'd see that I admit it can sound good. I'm not arguing against it's ability to sound fun, I'm simply stating that it's synthetic. The ambiance that (even proper) rear fill creates is a gimmick, a nice sounding gimmick perhaps, but a gimmick nonetheless.


----------



## thehatedguy

Stereo was intended to have 3 channels- l/c/r.


----------



## KillerBox

I don't care if my music was made for mono, 2 channel or 3 channel. If it sounds better on a gimmick 7.1 surround sound processor, then that is what I will use.

If it sounds better on just my front speakers in a 2 channel or 3 channel configuration, then I always have the option to turn off the Logic 7 processor and/or use the fader. 

So far, I haven't had anything that sounded worse because of the Logic 7 processor.


----------



## SSSnake

> So far, I haven't had anything that sounded worse because of the Logic 7 processor.


If you listen to music with interesting phase variations you will get VERY interesting output from logic 7 (I like logic 7, just saying).


----------



## Lanson

The thing I see out of all of this is, open source is the answer to all the problems. Solves the economic issue, solves the niche market issue because we don't need a company to involve themselves, etc. 

We need the ogg vorbis of surround sound. 

How this relates to the original post of amps, well... I'll have to get back to you on that.


----------



## msmith

We can't even agree on what stereo is supposed to sound like and you guys want to do surround sound. The arguments will be epic!


----------



## KillerBox

msmith said:


> We can't even agree on what stereo is supposed to sound like and you guys want to do surround sound. The arguments will be epic!


Let's start the arguments on surround sound before we all are too old to care :laugh:


----------



## Ziggyrama

gijoe said:


> That's what we here when we are where? That room that rear fill creates isn't in the recording, and wasn't in the recording studio. The music was most likely recorded in a booth the size of a closet and any sense of space that it has by the time you get the CD was added to it. That was the intention of the artist, by taking that CD that already had a "room" added to it, then making that room bigger with rear fill is a gimmick.
> 
> If they wanted it in the original recording, they could have added it.
> 
> 
> It doesn't bother me that people like it, and if you'd read my original post on the topic you'd see that I admit it can sound good. I'm not arguing against it's ability to sound fun, I'm simply stating that it's synthetic. The ambiance that (even proper) rear fill creates is a gimmick, a nice sounding gimmick perhaps, but a gimmick nonetheless.


Actually, I happen to work with people that used to work in recording studios so I asked as I am curious exactly how this is done. Turns out the setups vary greatly based on the studio. Some studios are fairly large, far bigger than any of my closets . The largest in my house is 9'x9'. Anyways, some production does capture the harmonics as well as some other shinnanigans that engineers decided to leave in, because it was fun, as I am told. I heard stories of drummers jumping off the set at the of the track which can be heard right at the end, if you listen carefully, lol. I also got to chat with Chris Clancy from Mutiny Within and their 2nd album was mixed at a house on a computer while their 3rd album was in a respectable studio in Britain. I said mixed because each instrument track was recorded separately in different countries, shipped to England and mixed. That means various stuff mixed in depending on which instrument you listen for, with various equipment competence. Lol. All I am saying, it is not sterile or synthesized by a computer in all cases. Love listening to these stories.

Sent from my Pixel using Tapatalk


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## benny z

Ziggyrama said:


> Actually, I happen to work with people that used to work in recording studios so I asked as I am curious exactly how this is done. Turns out the setups vary greatly based on the studio. Some studios are fairly large, far bigger than any of my closets . The largest in my house is 9'x9'. Anyways, some production does capture the harmonics as well as some other shinnanigans that engineers decided to leave in, because it was fun, as I am told. I heard stories of drummers jumping off the set at the of the track which can be heard right at the end, if you listen carefully, lol. I also got to chat with Chris Clancy from Mutiny Within and their 2nd album was mixed at a house on a computer while their 3rd album was in a respectable studio in Britain. I said mixed because each instrument track was recorded separately in different countries, shipped to England and mixed. That means various stuff mixed in depending on which instrument you listen for, with various equipment competence. Lol. All I am saying, it is not sterile or synthesized by a computer in all cases. Love listening to these stories.
> 
> Sent from my Pixel using Tapatalk




Justin Bieber records in studios all over the world which are weaved together in the final mix. Even vocal cuts from different studios - of the same song - are mixed/spliced together in the final mix.

Yes, I just referenced Justin Bieber. Publicly.


----------



## rton20s

Before we get too deep into the weeds (perhaps we are already there?) with center channels, rear fill, surround sound, upmixing, etc... Maybe it would be best to take the discussion to another thread. One not titled "Modern full-range Class D amplifiers." There has been quite a bit of discussion in the past on the subject on this site. One of the more recent threads is the one started to discuss Audiofrog's upmixing processor that is under development. 

http://www.diymobileaudio.com/forum/general-car-audio-discussion/291594-audiofrog-announces-new-multi-channel-platform.html

Much of the deeper discussion comes later in the thread, but it is worth the read if you're really interested in the topic.


----------



## gijoe

Ziggyrama said:


> Actually, I happen to work with people that used to work in recording studios so I asked as I am curious exactly how this is done. Turns out the setups vary greatly based on the studio. Some studios are fairly large, far bigger than any of my closets . The largest in my house is 9'x9'. Anyways, some production does capture the harmonics as well as some other shinnanigans that engineers decided to leave in, because it was fun, as I am told. I heard stories of drummers jumping off the set at the of the track which can be heard right at the end, if you listen carefully, lol. I also got to chat with Chris Clancy from Mutiny Within and their 2nd album was mixed at a house on a computer while their 3rd album was in a respectable studio in Britain. I said mixed because each instrument track was recorded separately in different countries, shipped to England and mixed. That means various stuff mixed in depending on which instrument you listen for, with various equipment competence. Lol. All I am saying, it is not sterile or synthesized by a computer in all cases. Love listening to these stories.
> 
> Sent from my Pixel using Tapatalk



My point is, adding ambiance and space by using rear fill (even if it's "proper" rear fill) is always synthetic, if the recording is in stereo. Regardless of the size of the room used to record (vocals are very often recorded in a booth) adding extra size after the fact is synthetic. 

My comments were never to bad mouth rear fill, they were to illustrate why more companies might not bother with adding it as an option to their DSP. 

In a stereo recording, as pleasant as it may be, any rear fill is synthetic. IT creates an illusion of a room that was not present in the recording the way it was mixed. It may sound better with it, but it still isn't authentic. 

It could be very possible that a band didn't want the reverb/ambiance that the room they recorded in created, so they fixed it during the mixing, adding your own synthetic version back into it when you listen is synthetic.


----------



## Holmz

fourthmeal said:


> The thing I see out of all of this is, open source is the answer to all the problems. Solves the economic issue, solves the niche market issue because we don't need a company to involve themselves, etc.
> 
> We need the ogg vorbis of surround sound.
> 
> How this relates to the original post of amps, well... I'll have to get back to you on that.


Well usually open source is referencing the software (source code).
Most of an amp is hardware.
If there was DSP in an amp, or some "Software Defined Radio" (SDR) style of control, then OpenSource would make sense.

Most amps (class A, AB, C) use an OP-amp or some differential pair as the driving stage that has the feedback control. There is little place for a digital control in a linear system.

Interestingly anologue computers were in fashion at a time. The amplifier is an analogue computer performing a times-X function in the gain stage. The output is doing more of an impedance matching function.
There is not a lot of elegance in a times-X function, and not a lot to be gained in doing it digitally.

In the class-D amp it differs in that the linear amp IS doing the Times-X function as a greater and lesser number (frequency) of digital pulses, and as it is digital the feedback and linearity could benefit from different S/W. whether is makes sense to replace the cheap driving chips with programable gates or a small CPU may be interesting... however it seems that if there are low THD+N Class-D amps then that problem has been solved.

It seems to me upon reflection, that OpenSource concepts can only relate to Class-D or DSPs, so it relates to this thread.


----------



## Lanson

But class D does not mean Digital.


----------



## Holmz

fourthmeal said:


> But class D does not mean Digital.


Class-D may not explicitly mean digital, but it sort does implicitly "mean" digital because the analog signal becomes a control for the switching... esscentially throwing in enough 1s to integrate up so as to follow the analogue signal.

A non switching amp, does not have any need for digital components, whereas a class-D requires some digital implimentation.


----------



## PPI_GUY

We did center channel back in the early 90's with either a specifically designed piece of gear like the Audio Control ESP-3 or a L-Pad. In the very early days we tried aiming summed mono tweeters off the windshield to create a center channel. LOL! 
With all the add-on features including EQ's, T/A and various crossovers available in state of the art DSP's I can't understand why some form of surround hasn't been included.


----------



## DPGstereo

PPI_GUY said:


> We did center channel back in the early 90's with either a specifically designed piece of gear like the Audio Control ESP-3 or a L-Pad. In the very early days we tried aiming summed mono tweeters off the windshield to create a center channel. LOL!
> With all the add-on features including EQ's, T/A and various crossovers available in state of the art DSP's I can't understand why some form of surround hasn't been included.



One issue is quality source material to listen to. Studio engineers were mixing in 5.1 for play back through sa/cd players. Now that hard-drive/storage is king ..I don't see many new releases advertising true surround recordings?
Plus, what do you really put in the rear channels? A live performance comes from in front of you. I guess one could argue for a LRC mix... but that can realistically be accomplished with 2-channel L,R fading. Guess that's why a lot of you guys don't care for rear fill speakers?


----------



## KillerBox

DPGstereo said:


> A live performance comes from in front of you. I guess one could argue for a LRC mix... but that can realistically be accomplished with 2-channel L,R fading. Guess that's why a lot of you guys don't care for rear fill speakers?


I would have to disagree with this statement. A live performance comes from all around you because of ambiance. 

In my 7.1 setup, a studio album sounds excellent with just a hint of ambiance. 

A well recorded live gives me goosebumps on the same system & it is the closest thing that I have heard to a live performance without actually being at one. To me there is no going back to just a 2.1 system.

I used to dislike most live recordings and now I am searching for them.


----------



## durwood

gijoe said:


> My point is, adding ambiance and space by using rear fill (even if it's "proper" rear fill) is always synthetic, if the recording is in stereo. Regardless of the size of the room used to record (vocals are very often recorded in a booth) adding extra size after the fact is synthetic.
> 
> My comments were never to bad mouth rear fill, they were to illustrate why more companies might not bother with adding it as an option to their DSP.
> 
> In a stereo recording, as pleasant as it may be, any rear fill is synthetic. IT creates an illusion of a room that was not present in the recording the way it was mixed. It may sound better with it, but it still isn't authentic.
> 
> It could be very possible that a band didn't want the reverb/ambiance that the room they recorded in created, so they fixed it during the mixing, adding your own synthetic version back into it when you listen is synthetic.


As long as you accept "stereo" is an attempt to recreate one space (the recording mix) into a different space (car, home, headphones, nature etc) there is nothing wrong with "synthetic". You have to accept that you are overlaying one space on top of another. Wherever you listen, just remember you are also listening to the room space too.

To know how much space should or shouldn't be there is a funny argument-one you will never (almost) know. If you do not care about space, and only about tonality then why not mono? What I think most people are really after is a sense of realism, and if the room makes the recording sound too small/big for what is being played (subjective) people will want to add "space"=(depth, width, instrument separation, ambiance) via synthetic means.


----------



## seafish

KillerBox said:


> Old School, JIM FOSGATES / GAVOTTE 360 DEGREES DIGITAL SPACE MATRIX fosgate NEW!
> 
> https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/173220058124


Well, also OT, but that was a good tip and a good deal!!!

I ordered about a week ago and since the seller takes returns, I figured I would return it if it dod not come with the toggle switch controller that are missing with most of these.

Well today I received it, and for $150, it was def BNIB and included the DIN wire harness with toggle switch controller as well as the installation and owners manual and also warranty registration. There was even a coupon to send in yo Fosagte Audionics to receive a complimentary "Your Ticket To Space" Poster that must have been part of the original marketing campaign. I am going to try sending in the coupon to see if I can still get a poster !!! JK/LOL!!!!

In any case, at some point I am going to play around with this on the test bench and compare it to the Ausiocontrol ESP3 I also have. MIGHT even eventaually use it an install !!:laugh:

KB, THANKS for the tip. There are still several units left if anyone else is interested.


----------



## bbfoto

I, too, love the DSP/Surround/Room Ambiance/Rear Fill discussion here, but this thread is about

*Modern full-range Class D AMPLIFIERS.*


----------



## stickpony

KillerBox said:


> I know we are getting off subject but, I had one of these in the 1980s & I was hooked.
> 
> It would be pretty bad to buy a state of the art new DSP, class D amps & run a 1980s surround sound processor!
> 
> Old School, JIM FOSGATES / GAVOTTE 360 DEGREES DIGITAL SPACE MATRIX fosgate NEW!
> 
> https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/173220058124


tell us about the Fosgate space Matrix please and yrou experience with it, im thinking about buying one


----------



## rton20s

bbfoto said:


> I, too, love the DSP/Surround/Room Ambiance/Rear Fill discussion here, but this thread is about
> 
> *Modern full-range Class D AMPLIFIERS.*


----------



## stickpony

seafish said:


> Well, also OT, but that was a good tip and a good deal!!!
> 
> I ordered about a week ago and since the seller takes returns, I figured I would return it if it dod not come with the toggle switch controller that are missing with most of these.
> 
> Well today I received it, and for $150, it was def BNIB and included the DIN wire harness with toggle switch controller as well as the installation and owners manual and also warranty registration. There was even a coupon to send in yo Fosagte Audionics to receive a complimentary "Your Ticket To Space" Poster that must have been part of the original marketing campaign. I am going to try sending in the coupon to see if I can still get a poster !!! JK/LOL!!!!
> 
> In any case, at some point I am going to play around with this on the test bench and compare it to the Ausiocontrol ESP3 I also have. MIGHT even eventaually use it an install !!:laugh:
> 
> KB, THANKS for the tip. There are still several units left if anyone else is interested.


Seafish,

be sure to post a thread with your comparison.. and post a link to it on this thread


----------



## PPI_GUY

seafish said:


> Well, also OT, but that was a good tip and a good deal!!!
> 
> I ordered about a week ago and since the seller takes returns, I figured I would return it if it dod not come with the toggle switch controller that are missing with most of these.
> 
> Well today I received it, and for $150, it was def BNIB and included the DIN wire harness with toggle switch controller as well as the installation and owners manual and also warranty registration. There was even a coupon to send in yo Fosagte Audionics to receive a complimentary "Your Ticket To Space" Poster that must have been part of the original marketing campaign. I am going to try sending in the coupon to see if I can still get a poster !!! JK/LOL!!!!
> 
> In any case, at some point I am going to play around with this on the test bench and compare it to the Ausiocontrol ESP3 I also have. MIGHT even eventaually use it an install !!:laugh:
> 
> KB, THANKS for the tip. There are still several units left if anyone else is interested.


Very interested to hear your impressions. Maybe post something in the Gear Reviews section here when you can?


----------



## seafish

stickpony said:


> Seafish,
> 
> be sure to post a thread with your comparison.. and post a link to it on this thread





PPI_GUY said:


> Very interested to hear your impressions. Maybe post something in the Gear Reviews section here when you can?




Gonna be awhile but surely will do!!!


----------



## KillerBox

For anyone interested, I started a new thread on Surround Sound, rear fill and center channel speakers.

http://www.diymobileaudio.com/forum...-channel-helpful-hurtful-car.html#post5383402


----------



## theobjectivist

Any thoughts why motorcycle amps arent popular?

In particular, im looking at biketronics with their Hypex design.

Their BT4180.14 puts out 180 Watts RMS X 4 and is 7"x5"x1.8"?


Tiny footprint, efficient Hypex design, US built, big power, no gain
This sounds perfect so what am I missing? (besides steep sticker price)



Ive searched diyma and only a few users are running them. Seems they really like them too. I dont know of any hypex amps on the market either.


----------



## rton20s

theobjectivist said:


> Any thoughts why motorcycle amps arent popular?
> 
> In particular, im looking at biketronics with their Hypex design.
> 
> Their BT4180.14 puts out 180 Watts RMS X 4 and is 7"x5"x1.8"?
> 
> 
> Tiny footprint, efficient Hypex design, US built, big power, no gain
> This sounds perfect so what am I missing? (besides steep sticker price)
> 
> 
> 
> Ive searched diyma and only a few users are running them. Seems they really like them too. I dont know of any hypex amps on the market either.


I think a lot of people are intrigued by the Biketronics/Hypex amps. But, lets be honest, are he Biketronics "typical" motorcycle amps? Not that I have ever owned a bike with a stereo, but I doubt it. At least, not in comparison to what you see from most of the bigger car audio brands. 

Other than the issues you mentioned of cost, it probably boils down to people being unaware that they exist, as well as the lack of a more powerful (or bridgeable) matching amp for subwoofers. The 2250 is a good start and can work for some lower power requirement installations (pair of IB subs, etc.), but doesn't really align with what most people are doing in car audio. Another hindrance may have been the built in HPF that Biketronics originally included on all of their amps. I believe it is now an option to have that disabled. 

When Victor Khat was still around, he always _talked_ about building some compact Class D amps based on the Hypex models that could set the car audio industry on its ear. But, at this point, talk is all it has been.


----------



## mitchell0715

I wouldn't be surprised if motorcycle oriented amps sound like **** because they're made to be loud


----------



## Holmz

mitchell0715 said:


> I wouldn't be surprised if motorcycle oriented amps sound like **** because they're made to be loud


What is the difference between them and other high power classD then?


----------



## JimmyDee

In an effort to help steer this thread back on track...
I just wanted to chime-in, as I've recently swapped my Zapco Z-LX amplifiers for a pair of MMATS HiFi-6150D amps.

I was skeptical, as my Zaps were amazing. Ridiculously clean and powerful. One of the best sounding amplifiers I'd ever heard.
I was a Class A/B fanboy. Big and heavy is what you need for clean powerful sound quality.
At least, that's what I thought; until a few weeks ago...

The MMATS (Class D) amps have impressed me in every way!
They are absolutely 'on par' with the Zapco amps I had previously (not better... definitely not worse).

Comparing a high-end Class D to a high-end Class A/B is something I never thought I'd do... but I do it confidently now. 
Class D has come a long way in the past 10 years, and there are some really nice amplifiers out there now.


----------



## mitchell0715

Holmz said:


> What is the difference between them and other high power classD then?


I have no idea, I'm speculating. 

One would think that if they're forcing it to be louder in a smaller package to fit on a bike, that there's some sacrifices that had to be made


----------



## mitchell0715

jimmydee said:


> In an effort to help steer this thread back on track...
> I just wanted to chime-in, as I've recently swapped my Zapco Z-LX amplifiers for a pair of MMATS HiFi-6150D amps.
> 
> I was skeptical, as my Zaps were amazing. Ridiculously clean and powerful. One of the best sounding amplifiers I'd ever heard.
> I was a Class A/B fanboy. Big and heavy is what you need for clean powerful sound quality.
> At least, that's what I thought; until a few weeks ago...
> 
> The MMATS (Class D) amps have impressed me in every way!
> They are absolutely 'on par' with the Zapco amps I had previously (not better... definitely not worse).
> 
> Comparing a high-end Class D to a high-end Class A/B is something I never thought I'd do... but I do it confidently now.
> Class D has come a long way in the past 10 years, and there are some really nice amplifiers out there now.


It amazed me how small and modular they are when I saw a few in person, truly some next generation amps


----------



## Holmz

mitchell0715 said:


> I have no idea, I'm speculating.
> 
> One would think that if they're forcing it to be louder in a smaller package to fit on a bike, that there's some sacrifices that had to be made


I dunno either.
Most all Class-D have higher power ratings than Class-A and AB.
Maybe that is what makes them sound better?
Or do class-D amps need more power to equal a class-A?
Or do people only rarely really use anywhere near their peak power? And have power stickers that are higher than what is needed?

There was at least on MC class-D that was supposed to be really outstanding.


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## piyush7243

theobjectivist said:


> Any thoughts why motorcycle amps arent popular?
> 
> In particular, im looking at biketronics with their Hypex design.
> 
> Their BT4180.14 puts out 180 Watts RMS X 4 and is 7"x5"x1.8"?
> 
> 
> Tiny footprint, efficient Hypex design, US built, big power, no gain
> This sounds perfect so what am I missing? (besides steep sticker price)
> 
> 
> 
> Ive searched diyma and only a few users are running them. Seems they really like them too. I dont know of any hypex amps on the market either.


In India I have installed BT4180 in multiple cars and they are as clean as it can get and immensely powerful. The small footprint and power requirements makes them ideal choice.

The sound is very clean,natural and has no colouration at all. Upon request they even provide xt20 connections with the amp making the wiring much easier.



Sent from my Pixel 2 XL using Tapatalk


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## Holmz

piyush7243 said:


> In India I have installed BT4180 in multiple cars and they are as clean as it can get and immensely powerful. The small footprint and power requirements makes them ideal choice.
> 
> The sound is very clean,natural and has no colouration at all. Upon request they even provide xt20 connections with the amp making the wiring much easier.


Those were the ones I was thinking of.


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## piyush7243

Holmz said:


> Those were the ones I was thinking of.


Just to add no gain controls or additional circuits make them pure SQ amps. I would say a sleeper of sorts.

Sent from my Pixel 2 XL using Tapatalk


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## mitchell0715

piyush7243 said:


> In India I have installed BT4180 in multiple cars and they are as clean as it can get and immensely powerful. The small footprint and power requirements makes them ideal choice.
> 
> The sound is very clean,natural and has no colouration at all. Upon request they even provide xt20 connections with the amp making the wiring much easier.
> 
> 
> 
> Sent from my Pixel 2 XL using Tapatalk


Thank you for that information. It's hard to know the facts without someone like you with actual experience providing insight


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## Gump_Runner

Your done? Thats it? What a thread.


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