# I want to check my calculations. Please critique.



## tspence73 (Oct 14, 2008)

Hi guys,

Yeah yeah. It's me. AGAIN. Mr. numbersboner. Deep breath. Exhale. Keep it clean and don't be willy nillies or jerks. Serious question and since it's audio related, I'm trying to be precise here and draw up my theory on setting the system starting with the subwoofers.

I will have two RE SE 12's coming tomorrow. I will set them up this weekend with my Cadence A7HC amp. I believe I have my math right, but you know me and details. We don't always mix, so here it goes. :blush:

I will be wiring the subs in parallel as a 1-ohm load. The Cadence amp will put out 1,200 watts RMS. I will be using a 0db 50Hz tone and my DMM to set the amp to 35 volts (square root of 1,200) to simulate a PEAK output signal to the amp. The subs will be mounted in a dual 1.0 cuft chamber which will yield a rather flat frequency response (or as close as I can get with this enclosure on this sub).

As you all know, my goal is to have as distortion-free an output as possible. By setting my amp gain to the RMS wattage, it will allow for plenty of headroom and close to distortion-free peaks as possible.

****Now, I will be assuming my SPL numbers WITHOUT factoring cabin gain.

1. The sensitivity of each sub is 86db 1w/1m. 
2. Each sub is dual voice coil. That means 4 coils.
3. The amp will be feeding each coil 300-watts PEAK (when music on a CD hits 0db max).

At PEAK output, here is how I figure the SPL using this site's calculator:
SPL Calculator

I start with a single coil at 300-watts:
1 watt = 86db
11 watts = 96db
111 watts = 106db
300 watts = 110db (according to the calculator in the link)

Add the 2nd coil @ 300-watts = 113db
Add the 3rd coil @ 300-watts = 116db
Add the 4th coil @ 300-watts = 119db

*So, at peak output the SPL should be able to reach 119db. Is this correct? *

Now, I'm not sure what the rules are for losses of SPL due to each coil sharing a woofer cone. So, that's the varible I'm looking for. Remember, this is when NOT factoring in cabin gain. Cabin gain will be addressed AFTER I've figured what the theoretical output is first. I intend to use equalization to minimize cabin gain when tweaking at the next step. 

The reason I'm setting the sub stage first is that it's usually the most distorted stage of a system and using it's initial setting as a way of tweaking the sound output of the other speakers should help keep audible distortion down. 

So, the question is, are my calculations for SPL correct without figuring in cabin gain?


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## mikey7182 (Jan 16, 2008)

Correct me if I'm wrong, but isn't it theoretically about a 3db gain every time you double wattage? If so, I think you're good up until you add the 3rd VC. At that point, I would think it should go from a 300w gain to a 600w gain for a 3db gain, right? So it should go 2nd VC- 300w: 113db, then 3rd/4th VC- 600w: 116db. Or, are you compensating for the 2nd woofer's cone area? I don't know that much about it... everything else sounds good. That was the only thing that sounded off to me.


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## tspence73 (Oct 14, 2008)

mikey7182 said:


> Correct me if I'm wrong, but isn't it theoretically about a 3db gain every time you double wattage? If so, I think you're good up until you add the 3rd VC. At that point, I would think it should go from a 300w gain to a 600w gain for a 3db gain, right? So it should go 2nd VC- 300w: 113db, then 3rd/4th VC- 600w: 116db. Or, are you compensating for the 2nd woofer's cone area? I don't know that much about it... everything else sounds good. That was the only thing that sounded off to me.


I'm waiting for the more engineer types to chime in. I've gotten clarification in the past that each coil does theoretically add another 3db, even if it's occupying the same driver. I just don't know what math to use to find the limitations of that stat. You simply add the same power to an additional speaker to get 3db. It's still "double the power". Each voice coil is technically "another speaker". I've thought about this extensively and just need a finer point of guidance on this. Chad or someone like him could help here.


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## ErinH (Feb 14, 2007)

look into SPL loss due to transfer through solids. That'll _really_ mess with your head...


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## mikey7182 (Jan 16, 2008)

bikinpunk said:


> look into SPL loss due to transfer through solids. That'll _really_ mess with your head...


Sounds like the farty Taco Bell dump I took earlier.


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## ErinH (Feb 14, 2007)

it's real. but, man, I can't remember much about it. I'll see if I can find any technical papers on the ASME site tomorrow...

In addition, I know I read/heard once that a panel flexing even in millimeters would result in SPL loss.


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## ca90ss (Jul 2, 2005)

You don't gain 3db for the 2nd vc in a dvc sub.


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## tspence73 (Oct 14, 2008)

ca90ss said:


> You don't gain 3db for the 2nd vc in a dvc sub.


Care to elaborate or show linky? Maybe something more than just sayin' it's so?


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## chad (Jun 30, 2005)

Hoestly I would run the amplifier at an impedance higher than one ohm in lieu of going for max power.

BUT the drivers have been purchased, oh well.


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## tspence73 (Oct 14, 2008)

chad said:


> Hoestly I would run the amplifier at an impedance higher than one ohm in lieu of going for max power.
> 
> BUT the drivers have been purchased, oh well.


It's going to be a 1-ohm load. Two DVC 4-ohm wired in parallel. I've spoken with a Cadence rep already and he indicated the subs should work fine with the amp at 1-ohm.


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## ca90ss (Jul 2, 2005)

The gain is from the extra power not the extra vc. If you give an 86db/1w dvc sub 1w per coil it's the same as giving a svc 86db/1w sub 2w of power. Same sensitivity and same total power applied whether through single or mulitple vc's gives the same output.


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## chad (Jun 30, 2005)

tspence73 said:


> It's going to be a 1-ohm load. Two DVC 4-ohm wired in parallel. I've spoken with a Cadence rep already and he indicated the subs should work fine with the amp at 1-ohm.


Rep does not equal engineer. Remember how we were talking about an amp NOT ACTUALLY putting out the same RMS voltage at low impedances as at high impedances? 1 ohm is a VERY low impedance (shuddup SPL guys) and I can certainly assure you that if you check the clip point of the amp unloaded it will clip MUCH sooner while loaded at one ohm. Find a scope and check it, I'm not ****ting you.


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## tspence73 (Oct 14, 2008)

ca90ss said:


> The gain is from the extra power not the extra vc. If you give an 86db/1w dvc sub 1w per coil it's the same as giving a svc 86db/1w sub 2w of power. Same sensitivity and same total power applied whether through single or mulitple vc's gives the same output.


Ok, so in principle either way it's the same result. On paper then it looks to be as I'm intending. Next we have the cabin gain to talk about. What will the SPL look like when figuring cabin gain? Will it be likely that it will look like what Andy Wehmeyer posted in that past thread? If so, then I think I have a solid plan mapped out to work with it, instead of against it by adding the midbass. I definitely want to HEAR the subs set the way I'm thinking before making any decisions. 

I'll actually heed you guys' advice to do more listening to the system before putting my ducks in a row on this one. I might end up not having nearly the bass I'm expecting by setting the amp so conservatively but then again that is one reason I went with larger subs and more power this time just to make sure I can get the best peak output with the least chance of it being too wimpy.


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## tspence73 (Oct 14, 2008)

chad said:


> Rep does not equal engineer. Remember how we were talking about an amp NOT ACTUALLY putting out the same RMS voltage at low impedances as at high impedances? 1 ohm is a VERY low impedance (shuddup SPL guys) and I can certainly assure you that if you check the clip point of the amp unloaded it will clip MUCH sooner while loaded at one ohm. Find a scope and check it, I'm not ****ting you.


Hmm. For the record Cadence is not trying to boast the amp will double it's power at half the ohm load. In fact they have put rather realistic specs out for it. 500-watts 4-ohm / 800-watts 2-ohm / 1,200-watts 1-ohm. That's pretty realistic. The video Cadence published of the new A7 amp is proof it very likely can do it's rated output. Cadence stated that the old A7HC amp will do pretty much the same power as the new A7. Do you still think I need a scope to verify this? I was planning on waiting and buying a scope in January. I couldn't wait to buy the subs. I jumped the gun. The 10" Pioneer sub just isn't going to cut it for me. I want more clean SPL!


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## chad (Jun 30, 2005)

those indeed are VERY realistic figures and Kudos to Cadence for that. BUT if you run it hard it's gonna get HOT, watch that at first. 

My motto, "The number one issue for longevity of electronics is heat cycling, followed closely by idiots with screwdrivers "


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## tspence73 (Oct 14, 2008)

chad said:


> those indeed are VERY realistic figures and Kudos to Cadence for that. BUT if you run it hard it's gonna get HOT, watch that at first.
> 
> My motto, "The number one issue for longevity of electronics is heat cycling, followed closely by idiots with screwdrivers "


I plan to set it in a conservative way, using it's 1200-watt RMS as the peak. The amp has enough ventilation too. It's under the passanger seat but gets a full 4.5 inches of clearance to get air. I don't plan on pushing it harder than it's rated output. Most of the time it will likely only be at half it's RMS or lower during playback.

Now back to cabin gain!  I'm excited to finally be able to test out my kooky ideas. One day when I get a sound processor like the MS-8 watch out. Tspence will be rolling with smooth thunder.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> I'm excited to finally be able to test out my kooky ideas.


Two RE 12's are a kooky idea? Kooky = two Strokers


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## ChrisB (Jul 3, 2008)

FYI: If you want to know the true SPL of your system, I am sure that some shop in Vegas would be glad to test your car with a Termlab for a nominal fee.

Secondly, running a Class D amp @ 1 ohm in a daily setup gets a big thumbs down from me. Class D amps run daily at 1 ohm have a shorter than usual life span. But hey, if you don't mind replacing your amp every few years, then go for it! Most 1 ohm setups I have heard also sound like garbage and I can't quite put my finger on if it is install dependent or if there is some truth to the fact that "barely above single digit damping factor sounds like poo" rumor.


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## tspence73 (Oct 14, 2008)

06BLMUSTANGGT said:


> FYI: If you want to know the true SPL of your system, I am sure that some shop in Vegas would be glad to test your car with a Termlab for a nominal fee.
> 
> Secondly, running a Class D amp @ 1 ohm in a daily setup gets a big thumbs down from me. Class D amps run daily at 1 ohm have a shorter than usual life span. But hey, if you don't mind replacing your amp every few years, then go for it! Most 1 ohm setups I have heard also sound like garbage and I can't quite put my finger on if it is install dependent or if there is some truth to the fact that "barely above single digit damping factor sounds like poo" rumor.


Perhaps one day I'll buy an even more insane amp for the subs and wire it 4-ohm series-parallel with 1,200-watts RMS. The A7HC amp is pretty much a solid design and is commonly run @ 1-ohm. It has another year of warranty if it comes down to it. For now it should serve it's purpose. 

The midbasses I plan on running will be powered off my Planet Audio amp @ 4-ohms and it has >400 damping factor. 

BTW, what is up with damping factor lately? I read somewhere that >50 damping factor would be inaudible in a blind test between two amps. Is that wrong info? Is there a subjective study/test paper showing that's not the case?


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## ChrisB (Jul 3, 2008)

tspence73 said:


> BTW, what is up with damping factor lately? I read somewhere that >50 damping factor would be inaudible in a blind test between two amps. Is that wrong info? Is there a subjective study/test paper showing that's not the case?


It depends! I have yet to be impressed with a 1 ohm Class D setup and I was always told it is the crappy damping factor. When a friend comes to the house and says "You gotta hear my new system", I pop in Raining Blood by Slayer to point out how inadequate their sub stage is! Then I take them to either one of my cars and show them how it is supposed to sound. 

I think the lack of fast bass drum reproduction is either a bad setup (box, sub placement, inadequate electrical, etc.), a bad tune (installer over zealous with gain/bass boost etc.), running the class d amp at ETA: 1 ohm mono (already hot enough to cook hot dogs by the time they arrive at my house), or a combination of all those previously mentioned factors.

Bottom line, if you like it and it sounds good to you, that is all that really matters in the end!


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## shadowfactory (Oct 20, 2008)

I run my Diamond D6 at 1 ohm for hours and it barely gets warm to the touch?  And have been doing so for 3 years now. I do want to get a new sub though and step up to 3 ohms and see if I can detect some improvement.


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> I run my Diamond D6 at 1 ohm for hours and it barely gets warm to the touch?  And have been doing so for 3 years now. I do want to get a new sub though and step up to 3 ohms and see if I can detect some improvement.


I wouldn't count on being able to detect a difference. Stang spoke about damping factor and for most if not all people, that spec when above 50 will be an inaudible difference. Perhaps when pushing that much wattage people can start to detect the difference in the 'feel' of the bass moreso than hear it. Many people have talked about a 'tactile' feel for bass that they consider part of 'hearing' it. This could be what 'stang is talking about. I would be interested in a real world high output subjective car audio test concerning damping factor and 'experiencing' bass from both a tactile and aural sense and find out if this causes a detectable subjective difference in damping factor.


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## chad (Jun 30, 2005)

Well, the cool thing is that he has enough to experiment with, I would be VERY interested in hearing his opinion of SQ of the amp at 4 ohms /vs/ 1 ohm even though at 4 ohms it will make a whopping 3dB less (calculated) I'll bet it's a bit less "care-free" sounding though


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## ChrisB (Jul 3, 2008)

tspence73 said:


> I wouldn't count on being able to detect a difference. Stang spoke about damping factor and for most if not all people, that spec when above 50 will be an inaudible difference. Perhaps when pushing that much wattage people can start to detect the difference in the 'feel' of the bass moreso than hear it. Many people have talked about a 'tactile' feel for bass that they consider part of 'hearing' it. This could be what 'stang is talking about. I would be interested in a real world high output subjective car audio test concerning damping factor and 'experiencing' bass from both a tactile and aural sense and find out if this causes a detectable subjective difference in damping factor.


Just because I haven't heard a 1 ohm setup that sounds good, doesn't mean that one can not be made to sound good. As for why the recent setups I have heard don't sound as good as I think they should, I don't know. All I know is that they sound OK on loose, rap style bass, but they can't play any speed metal double bass pumps or any other fast paced bass track with accuracy, and I want to know why that is myself.

Metal tracks I like to test with are:
As I Lay Dying - The Sound of Truth
Slayer - Raining Blood
Slayer - Disciple

I also test with Drum and Bass such as Chase & Status, Pendulum, and High Contrast. Of course, my favorite test CD of all times is Pink Floyd's Dark Side of the Moon!

Next on the docket, I am going to start using an older Bass Mekanik CD that a friend of mine gave to me this week! Tocatta in B and the 808 Tune Up seem like good tracks to test with.


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## ChrisB (Jul 3, 2008)

chad said:


> Well, the cool thing is that he has enough to experiment with, I would be VERY interested in hearing his opinion of SQ of the amp at 4 ohms /vs/ 1 ohm even though at 4 ohms it will make a whopping 3dB less (calculated) I'll bet it's a bit less "care-free" sounding though


I have a few amps to test with. I have the following amps that I am not using at the moment:

RF Power 351s
RF Punch P5002
Crossfire BMF 1000d
Soundstream Reference 700s
Orion HCCA 250 G4
Orion HCCA 225 G5
Linear Power 150
Linear Power 1502IQ
Linear Power 1752
Linear Power 5002
And I am sure I left one or two out because this is just off the top of my head.....

Right now I am currently using:
Civic:
Linear Power 1502IQ for Highs
RF 25 to Life Punch 150 - Subwoofer

Rustank:
RF 25 to Life Power 1000 - whole system

When I get bored, I am going to do some more playing around!


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## chad (Jun 30, 2005)

That's the thing that overly analytical people miss out on. The obsession with power combined with the mis-understanding that in a DD you will likely not notice the last 3 dB peeled off the tippy top in balls-out situations and it can actually sound better. BUT you have to get the analytical side out of your head, grab a beer, light a smoke, and head for the car with ONLY a screwdriver. Rewire, bring the gain up just a tad and see what you like better.


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## falkenbd (Aug 16, 2008)

Here is my challenge to you. Wire it up at 1 ohm, and take a listen for a few days(hopefully you don't burn up your amp first). Then wire it up at 4 ohms and take another listen for a few more days. I bet you'll like how it sounds in 4 ohms better, and it'll still be loud.

I personally have a DLS A6 running at 1 ohm daily, with no problems (its a different amp than your Cadence) - I ran it at 4 ohms for a few weeks first - I think I'm going to switch it back the next chance I get. The difference between 500 watts and 1200 watts was negligible in loudness. (Theoritically just over 3 db gained)

So after all of the threads in which you commented about setting gains you haven't learned that setting with a DMM is only going to get you in the ballpark????

Set them by ear thats how you'll end up with headroom.


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## falkenbd (Aug 16, 2008)

oh, and if you must calculate your SPL - use 1200 watts and add 3 db only for the extra sub.

1w 86
1w - 2 subs 89 db - and go from there


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## 14642 (May 19, 2008)

What is all of this talk about headroom? What are you guys talking about? Are you using some amps I don't know about which have super high voltage supplies but deliver little current so there's big power available for peaks that can't be sustained as RMS power? Setting your gain low doesn't give you more headroom.


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## tspence73 (Oct 14, 2008)

Andy Wehmeyer said:


> What is all of this talk about headroom? What are you guys talking about? Are you using some amps I don't know about which have super high voltage supplies but deliver little current so there's big power available for peaks that can't be sustained as RMS power? Setting your gain low doesn't give you more headroom.


What I'm doing is to set the amp using a 0db peak at the amp's RMS output. That way when a music cd hits the 0db peak, the amp is still using an unclipped output. I'm hoping I have enough headroom to pull this off. I might not. I may very well still need to clip some to achieve the bass I want. We'll see. I will use midbass drivers to add additional low bass and see what happens. If I'm still weak on bass after that, then it's either buy more powerful amps or accept that clipping is going to happen. I'm hoping I've shot for enough headroom to achieve the results I want with a non-clipped output.


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## chad (Jun 30, 2005)

I don't recall mentioning that lowering gain will increase headroom. I DO however recall saying and eluding to the fact that running an amplifier at a higher impedance will:

a: increase longevity
b: reduce heating
c: likely raise the efficiency in that mode of operation
d: recover from transients better
e: get darn near as loud (a casual operator will not miss the extra couple dB when running WFO)


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## ChrisB (Jul 3, 2008)

With regards to headroom, I believe it was Richard Clark who said that you needed 10x the RMS power handling of your speakers to ensure proper headroom. I don't know about anyone else here, but I can't afford the electrical system to support TEN TIMES the RMS power handling of my speakers.

In my Mustang that would equate to 7,000 watts RMS for my subwoofer and 4,000 watts RMS for my mids/highs.

ETA: I did set my 25 to Life Punch 150 to deliver 600 watts RMS into a 4 ohm mono load with a 0dB 50Hz test tone. I know the birth certificates are only a marketing tool, but I am sure that prior to my amp heating up, it can easily output the power rated on its birth certificate:


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## tspence73 (Oct 14, 2008)

06BLMUSTANGGT said:


> I have a few amps to test with. I have the following amps that I am not using at the moment:
> 
> RF Power 351s
> RF Punch P5002
> ...


I'm thinking that some cars have a boomy low end due to their acoustics. What it sounds like you're describing is that "one-note" bass from 30-50Hz that many cars are cursed with. With rap music, the bass sounds good. Just like my car. Then when rock music comes on and calls for snappy/sharp bass/midbass from 60Hz to 150Hz, the system comes up weak and without authority. This is how I would describe the sound I was getting. Boomy lows. Unbalanced bass response. Drums were only sharp when my comps were forced to play down to 60Hz with a 60Hz boost. My 10" sub would only seem to play that "one-note" bass with strength. Every other bass notes was wimpy and the sharp "snap" on drums were only there in my comps (which aren't made to produce bass properly). 

This is why I'm going for a midbass to "fill" this loose gap in my sound and sharpen up the bass/midbass attack. Way back, when I played with dynamics while trying to remaster music. The attack setting on the dynamics processor seems to somewhat simulate the kind of sound you say you like. What you're describing is what I'm trying to get. A more impacting ouput. Sharp/punchy and more well balanced with a bit of ultra low end to give the sound a sense of depth and realism.


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## ChrisB (Jul 3, 2008)

tspence73 said:


> I'm thinking that some cars have a boomy low end due to their acoustics. What it sounds like you're describing is that "one-note" bass from 30-50Hz that many cars are cursed with. With rap music, the bass sounds good. Just like my car. Then when rock music comes on and calls for snappy/sharp bass/midbass from 60Hz to 150Hz, the system comes up weak and without authority. This is how I would describe the sound I was getting. Boomy lows. Unbalanced bass response. Drums were only sharp when my comps were forced to play down to 60Hz with a 60Hz boost. My 10" sub would only seem to play that "one-note" bass with strength. Every other bass notes was wimpy and the sharp "snap" on drums were only there in my comps (which aren't made to produce bass properly).


I think you may be on to something. Many of the local "custom shops" use pre-fab, yes, I said PRE-FAB enclosures in their "custom" installs. In many cases, the driver is NOT properly matched to the enclosure. I have way too many examples to list, but I did purchase a pair of JL Audio 10w3v2s from a friend that were in a Nissan Titan Box. After displacement, I calculated the enclosure to be a little less than .4 cubic feet sealed. They effectively turned these subwoofers into midbass speakers!

As I said in another thread, matching your subwoofer to the proper enclosure is the first step you take. Matching the subwoofer setup to the car is a whole different ball game, and I would be willing to bet that most shops don't/can't/won't match the setup to the car.

Another thing I am seeing with the local "custom shops" is their overzealous use of bass boost. I have seen some setups where the bass boost was turned up to 3/4 of the way. Right off the bat, they are giving the system 12 dB of boost @ 45 or so Hz...

I got a kick out of one of the local shop managers asking me how much boost I was running on my 25 to Life Punch 150 in my Civic. You should have seen the look on his face when I told him NONE!



tspence73 said:


> This is why I'm going for a midbass to "fill" this loose gap in my sound and sharpen up the bass/midbass attack. Way back, when I played with dynamics while trying to remaster music. The attack setting on the dynamics processor seems to somewhat simulate the kind of sound you say you like. What you're describing is what I'm trying to get. A more impacting ouput. Sharp/punchy and more well balanced with a bit of ultra low end to give the sound a sense of depth and realism.


I wish you lots of luck with that because it seems to me like you are creating a tuning nightmare for yourself.


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## AndyInOC (Jul 22, 2008)

personally i took chads advice a few weeks ago as far as raising the impedance of my 2 12's and i can honestly say that there IS an audible difference, it seems to get just as loud but will dig deeper and stay cleaner with very little effort. This was a drop from around 600 watts @ 1 ohm to 250 watts @4 off the class d sub channel of a nine.5

Half the fun of our hobby is experimentation, at least try what others suggest, it's a matter of maybe 5 or 10 minutes to wire it and you may be pleasantly suprised.


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## rc10mike (Mar 27, 2008)

AndyInOC said:


> Half the fun of our hobby is experimentation, at least try what others suggest, it's a matter of maybe 5 or 10 minutes to wire it and you may be pleasantly suprised.


x2

I was running a Sundown 3000D @ 1ohm for the longest, then for the heck of it I re-wired it to 4 ohms, it still got loud enough for me, and sounded overall more dynamic and just plain better. I went in to the experiment thinking it would be a waste of time, it wouldnt be nearly as loud etc....


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## tspence73 (Oct 14, 2008)

Okay,

Go ahead and say "I told you so" and get it over with. I connected the new subs. Wired it to 1-ohm and, well. It sounds more like "FM Radio" bass. A bit compressed and 'mushy'. 

I will try to tweak it, play with it, etc. But even rap type bass is effected. All bass sounds seem to have the same volume with little variation. This is interesting. Perhaps it's as you all think. Something is 'not right'. Now I'm thinking if my tweaking attempts continue to fail me, I will try wiring series-parallel for a 4-ohm load and try 500-watts RMS. Even if it's a bit of clipping I'd rather have inaudible clipping than slow/mushy bass.


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## chad (Jun 30, 2005)

AndyInOC said:


> personally i took chads advice a few weeks ago as far as raising the impedance of my 2 12's and i can honestly say that there IS an audible difference, it seems to get just as loud but will dig deeper and stay cleaner with very little effort. This was a drop from around 600 watts @ 1 ohm to 250 watts @4 off the class d sub channel of a nine.5
> 
> Half the fun of our hobby is experimentation, at least try what others suggest, it's a matter of maybe 5 or 10 minutes to wire it and you may be pleasantly suprised.


That's GREAT news Andy!

Some people just get hung up on numbers and are dead-set in their ways. They forget to realize that even though an amplifier is STABLE at a certain impedance that does not mean that it's OPTIMAL. I'm stable carrying a 50 Lb feed-bag on each shoulder, that does NOT mean that I LIKE it


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## falkenbd (Aug 16, 2008)

tspence73 said:


> Okay,
> 
> Go ahead and say "I told you so" and get it over with. I connected the new subs. Wired it to 1-ohm and, well. It sounds more like "FM Radio" bass. A bit compressed and 'mushy'.
> 
> I will try to tweak it, play with it, etc. But even rap type bass is effected. All bass sounds seem to have the same volume with little variation. This is interesting. Perhaps it's as you all think. Something is 'not right'. Now I'm thinking if my tweaking attempts continue to fail me, I will try wiring series-parallel for a 4-ohm load and try 500-watts RMS. Even if it's a bit of clipping I'd rather have inaudible clipping than slow/mushy bass.



Crappy box???


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## ChrisB (Jul 3, 2008)

falkenbd said:


> Crappy box???


And/or the 1 ohm curse!


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## tspence73 (Oct 14, 2008)

falkenbd said:


> Crappy box???


No. Two highly recommended RE SE 12's in a optimum sealed enclosure. There is no reason for it. There are more tweaks I can try but it's seeming pretty lifeless on the bass despite having tons of head room and that it's very likely not clipping one bit. I'm frankly shocked it sounds worse than my highly clipped 10" Pioneer SPL sub. The two 12's have more bass, but it's, not punchy. It's blah. Hard to explain. I have a few other things to try, we'll see. I really want this to work the way I planned but I trust my ears before my numbers. The final test is how it sounds.


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## guitarsail (Oct 12, 2007)

haha...crappy box CONSTRUCTION...just becuase its RE spec'd...doesn't mean it was built well to RE spec...


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## chad (Jun 30, 2005)

guitarsail said:


> haha...crappy box CONSTRUCTION...just becuase its RE spec'd...doesn't mean it was built well to RE spec...


It's kinda tough to Eff Up a sealed enclosure.


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## guitarsail (Oct 12, 2007)

you would think soo..

but i'm just throwing it out there...i mean...seriously...

Ya know just kinda...tossin it out there see what sticks...

I mean at this point in the tspence experience...God himself may not even know what is going on to make them sound muddy...

(done in stewie rant on brians book writing voice, ever increasing pitch )


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## tspence73 (Oct 14, 2008)

chad said:


> It's kinda tough to Eff Up a sealed enclosure.


Agreed. This enclosure is built well enough. No leaks. No holes. 1.0 cuft sealed. Quality isn't an issue here.


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## chad (Jun 30, 2005)

Where are they crossed over?


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## tspence73 (Oct 14, 2008)

chad said:


> Where are they crossed over?


120Hz @ 24db octave.


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## ChrisB (Jul 3, 2008)

I think you have them crossed too high. You should set them between 60 and 80 Hz for optimal VBA!

ETA: I plotted 1.0 cubic foot per 12 sealed in Bass Box Pro and you should have optimal sub bass response with an enclosure at that particular size!


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## guitarsail (Oct 12, 2007)

Built well...fair enough..thought id toss it out there..upon further review...aka your xover points....they are WAY too high...way way tooo high...way way way too high...getting those down will help tremendosly


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## fredridge (Jan 17, 2007)

may not be an issue, but to some people

clipping = loud


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## tspence73 (Oct 14, 2008)

guitarsail said:


> Built well...fair enough..thought id toss it out there..upon further review...aka your xover points....they are WAY too high...way way tooo high...way way way too high...getting those down will help tremendosly


But my Infinity comps can't handle a 70-80Hz xover.  But I love the mids/hi's. I was going to surprise the forum and wait to announce, but I made a decision on my midbasses. I placed an order for the JL Audio ZR800-CW. I know some will say I overpaid and could have gotten just as good for less, but I just don't want to take chances. I want to have the best odds that this system turns out awesome.


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## chad (Jun 30, 2005)

guitarsail said:


> Built well...fair enough..thought id toss it out there..upon further review...aka your xover points....they are WAY too high...way way tooo high...way way way too high...getting those down will help tremendosly


Re-think that, if he's crossed that high then he's less likely to get that bloated low end bloom. If he said he was crossed at 60 or under the first ting I was going to recommend was to RAISE the crossover in order to apply more powere to an area, using large drivers, that would provide a bit more snap.


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## guitarsail (Oct 12, 2007)

chad said:


> Re-think that, if he's crossed that high then he's less likely to get that bloated low end bloom. If he said he was crossed at 60 or under the first ting I was going to recommend was to RAISE the crossover in order to apply more powere to an area, using large drivers, that would provide a bit more snap.


Well...its a first for us chad...sniff sniff..haha..When i cross my subs higher like around 100 for kicks and giggles...things just never go well in my car anyways...i drop em lower and they start to de-mud..whenever i cross mine high they get the bloated yucky bass sound...lower em and it all tightens up...my 2p worth


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## tspence73 (Oct 14, 2008)

Whoa,

On the drive home from work, I actually felt like cranking it up a bit. Suffice it to say my jaw was on the floor. Wow. This system could easily be tuned for a type of sound I'm not going for. But, it's nice to know it can do it. 

I played with some settings and found the subs crossed lower DO sound better and tighter. I can't wait to install my midbasses. The JL Audio ZR800-CW arrived! wow. Fast shipping. I ordered them on Friday!


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## tspence73 (Oct 14, 2008)

Oh, and here are the 10awg speaker wires (Blue Jeans Cables) and 4awg power lines tinned and screwed into the Cadence amp last night. They ain't giving me any more problems. I promise.  :









I tried to vaccum up I swear! :blush:

One of the RE SE 12's coming out of the box:


















Don't the manufacturers know by now? Me and manuals don't mix. Who needs those things? Sheesh!


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## tspence73 (Oct 14, 2008)

Is my system coming together or what fellas?


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## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> Is my system coming together or what fellas?


Good job. Tie down those cables close to the amp.


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## shadowfactory (Oct 20, 2008)

Nice to know you ignored everyone's advice and got those JL midbasses over all the other great, fantastic, amazing recommendations you were given. Why ask at all if you are going to ignore every answer given to you?


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> Nice to know you ignored everyone's advice and got those JL midbasses over all the other great, fantastic, amazing recommendations you were given. Why ask at all if you are going to ignore every answer given to you?


I didn't ignore the advice. I mulled it over for a full 3-weeks past the time I was going to order them. I went over every way I could make an 8-ohm set work and the only answer was to buy a dedicated amp for them. And I have no other seats to put an extra amp under and I'm trying to keep the install invisible/non-intrusive. 

Another reason for the JL selection is that it's a slim 3.36 inch mount and with my door's 2.75 inch rear mount limitations, the JL Audio midbass allows for a much smaller mounting ring than the Peerless. 

Believe me when I tell you that I wanted the Peerless to work, but it was obviously built for home audio and not for a car install. There are definite limitations to mounting it in a car and needing a powerful amp (like a dedicated 4-channel amp bridged to 2-channels) to power it to effective levels of output with proper headroom.

The ZR800-CW is a midbass specifically designed for a car install. Slim profile, 4-ohms, allowing for moderate amp power to achieve effective output results and a great infinite baffle performer. The only problem is that it cost more for a pair of the ZR800's than it did for my RE SE 12's. 

If I could have found a place to hide a 3rd amplifier, I would have bought another Planet Audio BB175.4B amp and used it bridged to power the Peerless woofers. So, for you to say that I completely went against advice, that's dead wrong. I looked over all the available information, made the best/reasoned and rational decision based on all the information. While it's certainly feasible (with the right equipment and liberal install conditions) to make the Peerless woofers work, I neither have the available power on my amp to properly power a pair of 8-ohm bass drivers (a good 175-200-watts @ 8-ohms would be more ideal), nor does my door have much room to mount the much thicker Peerless woofer. If you can't tell by how detailed my thinking has been in regards to this choice, then you must know by now that I didn't just "ignore" the advice. I made every attempt to make it work and delayed my purchase for 3-weeks agonizing over the decision and wanting to make the Peerless woofers work. 

I just don't want to buy the Peerless woofers, going against my better judgement regarding the conditions, just to make the crowd here at DIYMA happy, only to find out that I run into more hassles with making it fit in the door or later find out I definitely need a stronger amplifier to power them to get the output I want. With the ZR800's I can play things safe and have a better chance of things working out properly. Maybe now you'll understand why I made the choice I did. It was nothing personal against the DIYMA crowd.

Also, there is nothing at ALL wrong with the ZR800-CW. By all accounts it is a heavy weight contender of a mid-bass that is just as good or better than any of the other recommendations I was given. It's just that the ZR800's are expensive/overpriced. I'll agree there. But NOBODY said they are poor performers. If the conditions were better there is no doubt I would have bought the Peerless driver for less. Do you think I wanted to spend more than I needed?


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## falkenbd (Aug 16, 2008)

chad said:


> It's kinda tough to Eff Up a sealed enclosure.


not really. 

bad cuts, and poor construction could lead to a leaky flexible box.

its not very hard to do it right, but that doesn't make it tough to eff up...


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## chad (Jun 30, 2005)

guitarsail said:


> Well...its a first for us chad...sniff sniff..haha..When i cross my subs higher like around 100 for kicks and giggles...things just never go well in my car anyways...i drop em lower and they start to de-mud..whenever i cross mine high they get the bloated yucky bass sound...lower em and it all tightens up...my 2p worth


I guess what I was getting at is that many cross VERY low for my tastes, well into the region where the sub system is WAY int roll-off, then they bring the gains up to compensate. This usually yields a ****-ton of LOW bass and a giant gaping hole between the midbass' abilities and the point that the sub comes in to effectiveness. Often times when people complain of loose sloppy bass I recommend backing the gain down a bit and bringing the crossover up to bring more "snap" back into the rig and more cohesive output in an area where the group delay and phase response can be set up to blend with the mid-bass units more. Some of us here (not many) utilize higher sub crossovers and don't leave a hole between the pass bands, hell I have been known to even [gasp] overlap the sub and midbass a tad!


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## MarkZ (Dec 5, 2005)

chad said:


> I guess what I was getting at is that many cross VERY low for my tastes, well into the region where the sub system is WAY int roll-off, then they bring the gains up to compensate. This usually yields a ****-ton of LOW bass and a giant gaping hole between the midbass' abilities and the point that the sub comes in to effectiveness. Often times when people complain of loose sloppy bass I recommend backing the gain down a bit and bringing the crossover up to bring more "snap" back into the rig and more cohesive output in an area where the group delay and phase response can be set up to blend with the mid-bass units more. Some of us here (not many) utilize higher sub crossovers and don't leave a hole between the pass bands, hell I have been known to even [gasp] overlap the sub and midbass a tad!


x2.

In most cars I've heard, the biggest critique I usually have is in the 80-250Hz range, and that tends to really be problematic for rock and roll and some jazz, in particular. When people complain about sloppy bass, as you mention, it's the interface between the midbass and sub. Either their sub is crossed too low or their midrange speaker just can't deal with 80-100Hz. Unfortunately in a car we're often stuck with less than ideal midbass drivers, especially for people who insist on sticking with a two-way for whatever reason. That's when the sub has to help out.

I don't think I've ever had a system where I crossed the sub lower than 70Hz, and I've even had it as high as 120Hz in a couple setups I had ten years ago. These days it's a little lower, but balls to the wall midbass drivers help make that possible.


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## Jimi77 (Jul 4, 2005)

LOL - those JLs don't look "slim" at all; they appear to be ~3.5-4" deep. You think you door panel rattles now, wait until you put those in.


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> LOL - those JLs don't look "slim" at all; they appear to be ~3.5-4" deep. You think you door panel rattles now, wait until you put those in.


It's 3.36in mounting depth. My door is 2.75". A .75" - 1" mounting ring will be required and the doorpanel will need some fiberglass mod work. I'll be doing damping work on the panel during the mod to try and keep out the vibration sounds/buzzing. I don't know if I'll be successful but I'll try my best. The funny thing is that it's the frequencies from 70-120Hz that are the resonant frequencies of the plastic. Even with damplifier on the plastic, it doesn't help. I'm thinking of trying VE damper on the plastic instead to see if that works better.


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## 14642 (May 19, 2008)

THe sense of impact from bass and midbass has nothing to do with anything below 200Hz. Snappy midbas is a result of accurately reproduced harmonics at MUCH higher frequencies. Put on a pair of headphones, load your favorite song into Audacity, apply a 180Hz low pass filter and listen...

there's no impact at low frequencies...


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## chad (Jun 30, 2005)

Andy Wehmeyer said:


> there's no impact at low frequencies...


I tend to disagree, as would your colleges at JBL professional facing the other pond. 

Not that said harmonics don't make a HUGE difference but the fundamental is just as if not more important.


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## tspence73 (Oct 14, 2008)

Andy Wehmeyer said:


> THe sense of impact from bass and midbass has nothing to do with anything below 200Hz. Snappy midbas is a result of accurately reproduced harmonics at MUCH higher frequencies. Put on a pair of headphones, load your favorite song into Audacity, apply a 180Hz low pass filter and listen...
> 
> there's no impact at low frequencies...


Sorry to disagree here, but I've owned many very nice sets of headphones in my lifetime and I've never heard the same impact from drums/bass as I do from live speakers. Call it "tactile" or whatever, but in my opinion, impact and dynamics of bass are definitely in the bass region and can be heard as well as felt.


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## MarkZ (Dec 5, 2005)

Andy Wehmeyer said:


> THe sense of impact from bass and midbass has nothing to do with anything below 200Hz. Snappy midbas is a result of accurately reproduced harmonics at MUCH higher frequencies. Put on a pair of headphones, load your favorite song into Audacity, apply a 180Hz low pass filter and listen...
> 
> there's no impact at low frequencies...


I think you guys probably have different definitions of the word..


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## Mlstrass (Apr 22, 2006)

06BLMUSTANGGT said:


> Just because I haven't heard a 1 ohm setup that sounds good, doesn't mean that one can not be made to sound good. As for why the recent setups I have heard don't sound as good as I think they should, I don't know. All I know is that they sound OK on loose, rap style bass, but they can't play any speed metal double bass pumps or any other fast paced bass track with accuracy, and I want to know why that is myself.
> 
> Metal tracks I like to test with are:
> As I Lay Dying - The Sound of Truth
> ...


I would guess it's more of the sub, enclosure size/tuning, and HU tuning vs the actual amp ohm load. 

What subs have you heard that couldn't keep up? Also any bass boost or heavy EQ'ing on the bottom end will make most subs sound sloppy. I do a lot of enclosure builds for guys who listen to rap and that's how they set things up and it sounds like crap. 

I run my sub amps strapped at 1 ohm final, so .5ohm each. I also have the gain dialed WAY back for daily, so they're barely working. My set up has no trouble keeping with fast metal. They will also PUNCH you in the chest which is what I like at times and that's the reason I run 6k of power and 2 15's. 

I usually play Slayer "Dead Skin Mask", but I'll have to check out the others you mentioned. 

An amp designed to run at 1ohm and being played at 1ohm, shouldn't run any hotter then a 2ohm amp at 2ohm. 

I did 5-6 full tilt burps in a row last year at a get together and the amps were barely warm to the touch. The subs got a little stinky as I was burping at 31-33Hz which is well below box tuning...

I did finish 2 sealed enclosures last night, one for a 10" ID, the other for a 12" ID, so I'm interested to see how they sound as I've never heard an ID sub. I do expect output to be WAY less then what I'd want when I'm in a "crank it up" mood, but I'm curious to hear the SQ as I haven't heard a sealed sub since my old Tempest.


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## Mlstrass (Apr 22, 2006)

AndyInOC said:


> personally i took chads advice a few weeks ago as far as raising the impedance of my 2 12's and i can honestly say that there IS an audible difference, it seems to get just as loud but will dig deeper and stay cleaner with very little effort. This was a drop from around 600 watts @ 1 ohm to 250 watts @4 off the class d sub channel of a nine.5
> 
> Half the fun of our hobby is experimentation, at least try what others suggest, it's a matter of maybe 5 or 10 minutes to wire it and you may be pleasantly suprised.


Only way this would be a vaild test is if you used a DMM to set the power levels so they're the same at 1ohm and 4ohm. 

Why would it dig deeper wired at 4ohm as you've changed NOTHING but the power level to the sub? 

Perhaps by reducing the power level and "assuming" a ported box you've reduced the output at peak frequency of the box, which could now make the low end seem a little louder to the ear.


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## chad (Jun 30, 2005)

Mlstrass said:


> Only way this would be a vaild test is if you used a DMM to set the power levels so they're the same at 1ohm and 4ohm.
> 
> Why would it dig deeper wired at 4ohm as you've changed NOTHING but the power level to the sub?
> 
> Perhaps by reducing the power level and "assuming" a ported box you've reduced the output at peak frequency of the box, which could now make the low end seem a little louder to the ear.


Or maybe the amp and the vehicles electrical system is not under as much stress..... maybe?... possibly?..... I agree on needing to set levels correctly for comparison but IN THEORY it would NOT be as loud at 4 ohms and he would likely find it better at one ohm from the volume comparison alone.


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## guitarsail (Oct 12, 2007)

Well I've always said all the snap and definition "crack" as it were from a kick drum all come from 120Hz and up...this requires a GREAT midbass driver to handle it..you will get the impact and thump from the subs, but without a great midbass taking care of the upper end of the harmonics and such you will be missing the definition and crack of the kickdrum.


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## tspence73 (Oct 14, 2008)

chad said:


> Or maybe the amp and the vehicles electrical system is not under as much stress..... maybe?... possibly?..... I agree on needing to set levels correctly for comparison but IN THEORY it would NOT be as loud at 4 ohms and he would likely find it better at one ohm from the volume comparison alone.


You would be correct. When doing subjective comparisons with untrained listeners, the louder ouput is typically preferred and held up by the listener as 'better sounding'. This is why matching volume is critical in any subjective blind experiment and even trained listeners are influenced by volume differences at times.


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## Jimi77 (Jul 4, 2005)

guitarsail said:


> Well I've always said all the snap and definition "crack" as it were from a kick drum all come from 120Hz and up...this requires a GREAT midbass driver to handle it..you will get the impact and thump from the subs, but without a great midbass taking care of the upper end of the harmonics and such you will be missing the definition and crack of the kickdrum.



Agreed. Tspence is (probably) having problems due to a poor midbass driver (Infinity Reference).


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> Agreed. Tspence is (probably) having problems due to a poor midbass driver (Infinity Reference).


yo mama is a poor midbass driver.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> yo mama is a poor midbass driver.


In all seriousness, spense, that you had to get another midbass driver to make up for their lack of midbass is testament to their quality. But I do cheers you for making a decision, and I'm sure you'll enjoy the JLs once they're installed.


A couple questions, though:


How are you gonna deal with rattles now?

How does 8"s with 1" spacers in the doors and 6.5"s in kick panels = invisible

And, why if you wanted -12db eq at 50-55hz and down would you step up from a single 10" to dual 12"s?


Holler.


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## Knobby Digital (Aug 17, 2008)

dubble.


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## 14642 (May 19, 2008)

MarkZ said:


> I think you guys probably have different definitions of the word..


Yes, I think that's what has happened. Certainly, air has to move to feel the bass and that's not what I'm talking about. I'm talking about the snappy sound that everyone seems to want and that they believe they need a dedicated driver handling 70-200Hz to get. It's the slap of the thumb on a bass guitar that never seems to sound right. The difference between a real sounding slap and a dull, muddy sounding one is midrange and high frequencies and you can't get it if you tune for a big wide dip in the midrange or if 70-200Hz is too loud. I believe the words for it in the pro-sound vernacular are "cut" and "bite".


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## chad (Jun 30, 2005)

Jimi77 said:


> Agreed. Tspence is (probably) having problems due to a poor midbass driver (Infinity Reference).


Which is exactly WHY I kinda sorta recommended raising the crossover freq of the subwoofer, to take some of the heet off of the "midbass drivers" he has now and let them do their job as midranges


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## tspence73 (Oct 14, 2008)

icehole said:


> In all seriousness, spense, that you had to get another midbass driver to make up for their lack of midbass is testament to their quality. But I do cheers you for making a decision, and I'm sure you'll enjoy the JLs once they're installed.


The Infinity comps have an fs of 95. The recommended crossover for it's 90-watt RMS rating is 100Hz. I am applying over 100-watts quite a bit, pushing the driver to it's thermal limits. This driver at this wattage should be highpassed at 120Hz with a decently steep octave. This is WHY I'm going with a midbass. BECAUSE I'm increasing my SPL. In order to keep the mid/hi's which I really like on these and still get the power handling, I am pushing the highpass above even it's lowest impadence curve (200-300Hz, I will use 400Hz, which should improve power handling). In other words, I will have my midrange/high-range cake and eat it too! 



> A couple questions, though:
> 
> 
> How are you gonna deal with rattles now?


I will be doing surgery on the door panel anyway. I will try my best.



> How does 8"s with 1" spacers in the doors and 6.5"s in kick panels = invisible


I will try to do this area as tastefully as possible and try to match it to the interior.



> And, why if you wanted -12db eq at 50-55hz and down would you step up from a single 10" to dual 12"s?


If you read enough of my previous posts, you would know that I found my sub amp was previously set too high and was clipping. I decided to upgrade to two subs and run @ 1-ohm then set the volume in a territory that isn't clipping. It actually has worked. I get a touch more bass out of my system now and it's set not to clip at all.




> Holler.


You don't got to holla.


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## tspence73 (Oct 14, 2008)

Andy Wehmeyer said:


> Yes, I think that's what has happened. Certainly, air has to move to feel the bass and that's not what I'm talking about. I'm talking about the snappy sound that everyone seems to want and that they believe they need a dedicated driver handling 70-200Hz to get. It's the slap of the thumb on a bass guitar that never seems to sound right. The difference between a real sounding slap and a dull, muddy sounding one is midrange and high frequencies and you can't get it if you tune for a big wide dip in the midrange or if 70-200Hz is too loud. I believe the words for it in the pro-sound vernacular are "cut" and "bite".


I think the Ref comps have excellent midrange. The vocal character is perfect. The highs, when properly set are real sounding, not tinny or 'fake'. The only problem I have is that the mids are totally off-axis and what I would call the "stereo image" is missing spacial cues. I can hear extreme right and left but other than that it sounds a bit 'wrong'. And it's not because of the speakers. When I lean my head down to listen to them on-axis, they sound unbelievably good. I frankly can't wait to move them to the kick panels to do dedicated midrange and not have an ounce of strain on them from the bass region and have them firing on-axis.


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## Knobby Digital (Aug 17, 2008)

I'm just gonna throw out this suggestion before you start fabbing...

Your new JL 8"s will comfortably play up to at least 200-300hz. So why not use that to your advantage and get a 4" component set to use them with? If Infinity makes a 4" Ref series, you could just get the mid driver and use your existing passive xover/tweet since you seem to like them so much. Or even get the 5.25" Ref.


A couple inches is a **** ton when you're in such close quarters, and it's just totally pointless to have both an 8" and a 6.5" configged the way you're planning. Not saying you can't get it to sound good, but it could be done alot easier and cleaner. -Not to mention more invisibly.



And regarding your sub, if it was clipping, why not just turn it down to accomplish your -12db goal, or has that been thrown out the window?


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## tspence73 (Oct 14, 2008)

When is a good deal on fiberglass work enough to not DIY? I was calling around to shops out of curiosity and found one shop that quoted me both the door midbass install with doorpanel mods AND a custom kick panels for my comps for $650. Seems like a great deal. Nobody else seems to be that cheep.


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## [email protected] (Jun 12, 2008)

tspence73 said:


> When is a good deal on fiberglass work enough to not DIY? I was calling around to shops out of curiosity and found one shop that quoted me both the door midbass install with doorpanel mods AND a custom kick panels for my comps for $650. Seems like a great deal. Nobody else seems to be that cheep.


that is cheap, better make sure the quality of work is there, which most likely wont be the best, unless you researched the shop and seen some of their glass work.

They also might do great work and are just bidding it cheap to get work, I bet with the eceonomy the way it is, the brick and mortar stores are crying for business.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> When is a good deal on fiberglass work enough to not DIY? I was calling around to shops out of curiosity and found one shop that quoted me both the door midbass install with doorpanel mods AND a custom kick panels for my comps for $650. Seems like a great deal. Nobody else seems to be that cheep.


Worth it is completely up to you, but somethings shouldn't be bargain shopped around.

Have you seen their work? Even if you have, and you like what you've seen it's still a gamble.


You seem to like things done your way, and (without unlimited funds) the only way to assure that happens is if you do it yourself.


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## tspence73 (Oct 14, 2008)

icehole said:


> I'm just gonna throw out this suggestion before you start fabbing...
> 
> Your new JL 8"s will comfortably play up to at least 200-300hz. So why not use that to your advantage and get a 4" component set to use them with? If Infinity makes a 4" Ref series, you could just get the mid driver and use your existing passive xover/tweet since you seem to like them so much. Or even get the 5.25" Ref.


I know that the comps I have sound just how I want. I just don't want to mess with that and take the chance it doesn't sound how I want. 



> A couple inches is a **** ton when you're in such close quarters, and it's just totally pointless to have both an 8" and a 6.5" configged the way you're planning. Not saying you can't get it to sound good, but it could be done alot easier and cleaner. -Not to mention more invisibly.


I will review the measurements and make a mock cardboard kickpanel and see how it looks. If I can get it done clean then I'll go through with it. If I can't, then it won't be easy to fine a 4" mid ref series 4-ohm from 2007's model line. They have been discontinued and the new series are 2-ohm and are likely to sound different. I did my listening tests and found the 6010cs were the best. I just don't want to mess with that if I can help it.



> And regarding your sub, if it was clipping, why not just turn it down to accomplish your -12db goal, or has that been thrown out the window?


No. If I turn down the 10" sub, what other frequencies go with it? Are the squeaky gears a turnin'? Ah, that's right, 60Hz-120Hz are reduced along with it. I don't think so. My goal is having MORE than I need. Turning it down and then having controlled, smooth, responsive sound that is accurate and has low distortion not just from producing the sound accurately, but also from a lack of mechanical noise from the moving drivers. Effortless sound that can still be dynamic and strong when called upon.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> No. If I turn down the 10" sub, what other frequencies go with it?... 60Hz-120Hz are reduced along with it.


Aren't you about to install some 8's in your doors that will play to 60hz?


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## falkenbd (Aug 16, 2008)

before paying for or doing that work, if I were you - I'd try to build some mock up enclosures in order to at least listen to the drivers the way you are hoping to listen to them in your car.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> I did my listening tests and found the 6010cs were the best. I just don't want to mess with that if I can help it.


Comparing 6.5" and 4" 2-ways is one thing, but now you'll be comparing 8/6.5/tweet to 8/4/tweet. BIG difference.


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## chad (Jun 30, 2005)

tspence73 said:


> When is a good deal on fiberglass work enough to not DIY? I was calling around to shops out of curiosity and found one shop that quoted me both the door midbass install with doorpanel mods AND a custom kick panels for my comps for $650. Seems like a great deal. Nobody else seems to be that cheep.


I have to say that i would only spend that much money on materials for my car, which that amounts equates to my headunit and amplification. This is why I'm at this site, the sole reason, the drive to get **** done for myself.

But whatever floats your boat mang


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## tspence73 (Oct 14, 2008)

BeatsDownLow said:


> that is cheap, better make sure the quality of work is there, which most likely wont be the best, unless you researched the shop and seen some of their glass work.
> 
> They also might do great work and are just bidding it cheap to get work, I bet with the eceonomy the way it is, the brick and mortar stores are crying for business.


It is a good deal. I haven't seen their work yet. I just called around. I will check them out, just to be thorough. If I end up having a shop do the work for that little and it turns out good, I rep the hell out of them for sure. Otherwise, doing it myself, I'll probably end up poisoning myself with fumes or ruining a few molds and other blunders I'm sure. I'm a total amatuer when it comes to arts and crafts. It would be cool to get guidiance and pictures and step by step instructions.  So, yeah, I'm a bit nervous about doing it myself. :blush:


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## Knobby Digital (Aug 17, 2008)

chad said:


> the drive to get **** done for myself.


Zackly!!!


Dirty hands and experience = feeling of accomplishment and empowerment

Paying to get something done = Hope it works out cause I gotta get back to work!


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## falkenbd (Aug 16, 2008)

If I could go back and choose paying to get my sub boxes done and doing them myself...

I think I'm glad I did them myself, even tho they are not finished they work.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> The Infinity comps have an fs of 95. The recommended crossover for it's 90-watt RMS rating is 100Hz. I am applying over 100-watts quite a bit, pushing the driver to it's thermal limits. This driver at this wattage should be highpassed at 120Hz with a decently steep octave. This is WHY I'm going with a midbass. BECAUSE I'm increasing my SPL. In order to keep the mid/hi's which I really like on these and still get the power handling, I am pushing the highpass above even it's lowest impadence curve (200-300Hz, I will use 400Hz, which should improve power handling). In other words, I will have my midrange/high-range cake and eat it too!
> 
> I will be doing surgery on the door panel anyway. I will try my best.


That's exactly why it's a crappy midbass driver. FS of 95hz - it doesn't even qualify as a midbass driver IMHO. 

I think you best approach for the door is to trowel on ~10 tubes of a high quality silcon caulking and back that with heavy duty aluminum foil before the silicon sets. Maybe throw in some fiberglass clothe or chop mat to stiffen things up.


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## Knobby Digital (Aug 17, 2008)

Jimi77 said:


> it doesn't even qualify as a midbass driver IMHO.


My sentiments exactly. A car 6.5" midbass that needs to be x'd at 120 isn't worth its space, and should be replaced with either a better 6.5", or in T's case, a proper midrange speaker.



But Spence, please just help me wrap my head around this. Let me know what points, if any, I'm understanding correctly. The actual numbers are rough.

For your install:

1. Your old single 10" sub was fine <50-55hz, but couldn't do 60-120hz loud enough without clipping, so you replaced that single 10" with dual 12"s.

2. Also at the same time, you bought a pair of 8"s to put in your doors to be used in the ~50-400hz range.

3. You still have reservations with using EQ and TA.

4. You spent over $500 on speakers without considering trying to process your existing equipment further, or trying out a set of say $60 PG RSD's.


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## ChrisB (Jul 3, 2008)

tspence73 said:


> When is a good deal on fiberglass work enough to not DIY? I was calling around to shops out of curiosity and found one shop that quoted me both the door midbass install with doorpanel mods AND a custom kick panels for my comps for $650. Seems like a great deal. Nobody else seems to be that cheep.


Ouch, $650 for kicks.... I didn't pay that much for version 1 of the WHOLE system in my 1997 Civic!


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> It is a good deal. I haven't seen their work yet. I just called around. I will check them out, just to be thorough. If I end up having a shop do the work for that little and it turns out good, I rep the hell out of them for sure. Otherwise, doing it myself, I'll probably end up poisoning myself with fumes or ruining a few molds and other blunders I'm sure. I'm a total amatuer when it comes to arts and crafts. It would be cool to get guidiance and pictures and step by step instructions.  So, yeah, I'm a bit nervous about doing it myself. :blush:



Just keep in mind that looks good and sounds good are 2 different things. I agree that you should go to a 4-5" midrange. Personally I'd step up from the Refs, but since you seem to think they're perfect. I certainly wasn't impressed with the set I owned; good value for a temp install, but no where near the quality drivers that I would use in a custom install.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> Do you think I wanted to spend more than I needed?


No I think you have a giant hard on for retarded wattage figures and refused to accept an 8 ohm driver would have worked just fine in your setup without a new amp.


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## tspence73 (Oct 14, 2008)

06BLMUSTANGGT said:


> Ouch, $650 for kicks.... I didn't pay that much for version 1 of the WHOLE system in my 1997 Civic!


No it's $650 for kicks + door mod/midbass install. The metal of the door may need to be cut to fit the 8" in the 6x9" hole. It's not a whole lot for fiberglass work on two areas.


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## tspence73 (Oct 14, 2008)

icehole said:


> My sentiments exactly. A car 6.5" midbass that needs to be x'd at 120 isn't worth its space, and should be replaced with either a better 6.5", or in T's case, a proper midrange speaker.
> 
> 
> 
> ...


The RE SE 12's set at 1,200-watts with a 50Hz 0db tone seem to have a perfect amount of bass output for me. They are doing just a tad more bass than my single 10" but are not set to clip one bit. I would say these are perfect and fit precisely what I was looking for. I'm not using them nearly to their potential output, but my goal wasn't to blow up the block but to have an effortless, smooth, accurate output at any volume level. These subs and amp are doing this perfectly.



> 2. Also at the same time, you bought a pair of 8"s to put in your doors to be used in the ~50-400hz range.


I am taking a bit of a risk here. If it's set and tweaked properly I should have zero additional noise from the speaker reaching it's physical limits like I was when I forced the Infinity comps to do 70Hz @ high output. Now, I'm hoping to only get noise from the door panel itself. Then I will fix that with some creative ideas.



> 3. You still have reservations with using EQ and TA.


No. I have an EQ on my HU that I use. I will eventually use an EQ after I finish my acoustic treatment phase in February thru May.



> 4. You spent over $500 on speakers without considering trying to process your existing equipment further, or trying out a set of say $60 PG RSD's.


The equipment was targeted for a specific set of parameters and I've stated them so many times you should know them by now. I found that because my comps were better suited as midranges at the SPL levels and for the dynamic headroom I was trying to accomplish, I would buy for more output than I needed. This system is about having excess but not using it all all the time. And no, I'm keeping the Infinity Reference comps. People seem to think I'm kidding when I say I believe they are the best car audio mid/tweets I've ever heard, but, they are. So, why would I replace the best?


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## tspence73 (Oct 14, 2008)

New pics of my RE's in the trunk:




























The wiring is with 10awg speaker cables with bannana plugs from Blue Jeans Cable.


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## ChrisB (Jul 3, 2008)

Where do you put your groceries?


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## tspence73 (Oct 14, 2008)

06BLMUSTANGGT said:


> Where do you put your groceries?


Who needs groceries? lol. No, seriously, the trunk is much deeper than it looks in the picture. I rolled the 67 pound sub box on it's back so that I could take a picture of it. The sub is normally firing forward and scooted closer to the back seats. I get almost 2 feet of of space behind the subs normally.

So Mr. Mustang. Do I finally have VBA? Hmm?  The trunk has officially been "tspence'd" haha.


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## falkenbd (Aug 16, 2008)

uhm.... turn those bad boys around... face them towards the rear.... you'll likely gain output. cancellation is probably killing your output while facing forward...


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## tspence73 (Oct 14, 2008)

falkenbd said:


> uhm.... turn those bad boys around... face them towards the rear.... you'll likely gain output. cancellation is probably killing your output while facing forward...


Is that why the phase switch on my amp worked to improve the sound? I like my subs firing forward though. I always figured people face them backwards just to show off and that's not what my intentions are with this system. It's all about SQ and business.

I hated losing the trunk space by going to two 12's, but it was necessary.


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## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> Is that why the phase switch on my amp worked to improve the sound? I like my subs firing forward though. I always figured people face them backwards just to show off and that's not what my intentions are with this system. It's all about SQ and business.
> 
> I hated losing the trunk space by going to two 12's, but it was necessary.


Aiming a woofer box in a car trunk - bass cancelation -


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## tspence73 (Oct 14, 2008)

Here's my previous sub in the trunk:


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## ChrisB (Jul 3, 2008)

Aiming the subs towards the trunk/rear bumper sometimes allows you to benefit from cabin gain. 

I know someone who lost just over 3 db when he turned his subwoofer box around and made it direct fire into the cabin! Basically, he made a baffle and sealed the front of the sub enclosure from the trunk. He was literally shocked when his DB #s dropped at the last competition that he went to!

This is a current trunk shot of my Civic:









This is what my Mustang is sort of looking like:


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> The RE SE 12's set at 1,200-watts with a 50Hz 0db tone seem to have a perfect amount of bass output for me. They are doing just a tad more bass than my single 10" but are not set to clip one bit. I would say these are perfect and fit precisely what I was looking for. I'm not using them nearly to their potential output, but my goal wasn't to blow up the block but to have an effortless, smooth, accurate output at any volume level. These subs and amp are doing this perfectly.
> 
> 
> 
> ...



Fair enough, I suppose. But you've spawned a couple questions.


Did you ever once think that you may be able to get alot more sound out of your existing equipment (including the Finitys) by further processing, and learn alot in the process?

Do you know that by putting a proper EQ last on your shopping list, you've retarded your learning curve, and it may have caused you to misunderstand your goals and buy unnecessary equipment?

Do you understand that 'efficiency' is a somewhat holistic term that's not limited to the sensitivity rating of speakers?

Have you actually heard any components sets that aren't sold OTC?


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## tspence73 (Oct 14, 2008)

I will try turning the subs around. But I like the physical 'punch' from the subs. If I turn them around my trunk lid will probably start buzzing and complaining. haha.

February's acoustic treatment phase can't get here fast enough. The cost and scale of this car system has taken on a new form. I'm probably obsessed now. Most people would think I have a greatly distorted idea of what's important. Oh well. This audio system will someday be one of the top mobile audio systems in my state, from a SQ perspective. When all the projects are done and months and months of listening and tuning have passed, I'll bet I will have a smile everytime I listen to my system.


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## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> I will try turning the subs around. But I like the physical 'punch' from the subs. If I turn them around my trunk lid will probably start buzzing and complaining. haha.
> 
> February's acoustic treatment phase can't get here fast enough. The cost and scale of this car system has taken on a new form. I'm probably obsessed now. Most people would think I have a greatly distorted idea of what's important. Oh well. This audio system will someday be one of the top mobile audio systems in my state, from a SQ perspective. When all the projects are done and months and months of listening and tuning have passed, I'll bet I will have a smile everytime I listen to my system.


Don't know if this has been mentioned or if its possible for you but you can have the best of both worlds if you build a IB style wall for the box while its facing forward. 

This will keep the bass from rapping around the box , going into the trunk, and coming back to cancel the waves. While still focusing the kick into the cabin instead of at the trunk lid.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> Most people would think I have a greatly distorted idea of what's important. Oh well.


The thing is that we all have the same idea of what's important to a large degree. I think most people's idea of SQ is at least very similar, but definitely not the exact same.



Honestly, I'm not trying to diss on you. I'm really just curious if you made any of those considerations I asked, and if you've actually heard any speakers that aren't mounted in soundrooms in local stores.


I think the products you just bought are great.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> Is that why the phase switch on my amp worked to improve the sound? I like my subs firing forward though. I always figured people face them backwards just to show off and that's not what my intentions are with this system. It's all about SQ and business.
> 
> I hated losing the trunk space by going to two 12's, but it was necessary.


OMG. I'm certain I told you where to place and aim the subs..... Oh well, as you've demonstrated time and time again, you don't listen to sage advice.

Eddie Runner's "tutorial" on where to place you sub.

Aiming a woofer box in a car trunk - bass cancelation -

Take note of the massive cancellation at ~100hz in the Jetta and Neon (the closest to your car).

Aiming Part 2


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> Do I finally have VBA? Hmm?  The trunk has officially been "tspence'd" haha.


Yeah you sure tspence'd the **** out of your subs by facing them towards the back seat. 

Also to chime in on the 1 ohm sub discussion, I just switched my 15" from 1 to 4 ohms so theoretically from 1500 watts to 375 watts and it is really only a minor difference in output, but the quality has gone up dramatically, there is so much more texture and precision at 4 ohms. It was a great change and I'm going to keep it that way.


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## slvrtsunami (Apr 18, 2008)

Normally, when it comes to this site, I try to keep it cordial and friendly. But I must say that Tspence's thread have become a great source of amusement. As I read it, this individual is obsessed with getting the best he can WITHOUT really wanting any help. That is shown by his questions asked, getting sound and solid advice from MULTIPLE people, but yet going his own way. This has NOTHING to do with product selection and purchase's; it is the overall principle. Again, I commend Chad and Andy and others willing to chime in with their advice as I have learned a lot. Even though my application, goals and car is different. I wonder if he realizes just how much combined experience and knowledge he really has giving him advice and suggestions. I don't know, if it was me, I would probably stop wasting my time knowing that either my advice will be totally ignored, or misconstrued to some degree or even attacked as being 'wrong' in one way or another.


OK, rant over. Spence don't even bother explaining yourself or your 'goals'. I really don't care and am not interested.

Thanks for your time.


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## chad (Jun 30, 2005)

shadowfactory said:


> Also to chime in on the 1 ohm sub discussion, I just switched my 15" from 1 to 4 ohms so theoretically from 1500 watts to 375 watts and it is really only a minor difference in output, but the quality has gone up dramatically, there is so much more texture and precision at 4 ohms. It was a great change and I'm going to keep it that way.



I'm converting you all one beer at a time 

Took less than one beer to do it right? That experiment is a REAL eye opener and it's so free it's not even funny. I remember having that issue in live sound in the 2 ohm /vs/ 8 ohm debate , it REALLY makes a difference when you are running balls out for hours on end. That was one of the most satisfying bets I have ever won. Especially since it happened behind the scenes and the clueless "enjaneir" thought we actually doubled the power as per his request  "So much more headroom man, I love you, thanks for going thru all the trouble man, I can't believe the distro supported it [added power]"


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## chad (Jun 30, 2005)

slvrtsunami said:


> Again, I commend Chad and Andy and others willing to chime in with their advice as I have learned a lot.


A. I have an 8 year old boy that already knows the ways of the universe, he will be an astro physicist by 8 1/2....... in his eyes.

B. I work at a university and teach kids 10-11 years older than my son that are even worse, at least my 8 year old knows the term "Trust me, I've done this MANY TIMES, it will all work out."


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## MarkZ (Dec 5, 2005)

tspence73 said:


> I will try turning the subs around. But I like the physical 'punch' from the subs. If I turn them around my trunk lid will probably start buzzing and complaining. haha.


Probably not. As the Eddie Runner article mentions (I think -- it's been a while), it's not the aiming so much as the position of the sub. When you turn the box around, the cone is closer to the bumper and therefore will be less perturbed by reflections (cancellation) at the frequencies we care about.

Low frequencies are non-directional (kinda sorta). The low freq ...um..."pressure" within the trunk isn't going to really change much by allowing the sub to face the trunk lid. So I'd be surprised if it buzzed anymore than it would if you simply upped the gain.


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## chad (Jun 30, 2005)

in other words, turn it around and move it all the way to the back of the trunk so that the actual driver is as close tot he trunk latch as possible  SHAZAM!


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## tspence73 (Oct 14, 2008)

slvrtsunami said:


> OK, rant over. Spence don't even bother explaining yourself or your 'goals'. I really don't care and am not interested.
> 
> Thanks for your time.


If you weren't really interested, then what was the point of posting in my thread exactly? Just curious.


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## slvrtsunami (Apr 18, 2008)

just venting and letting my personal opinion be known, nothing personal just business.


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## Knobby Digital (Aug 17, 2008)

slvrtsunami said:


> personal opinion


Let the record also show that it's a very popular opinion.


Spense, alot of people are upset when they see someone with genuine interest and enough money allow poor perspective, philosophy, and pride to stand in the way of efficiency and accomplishment -especially when they're in dire need of help. 

When it's as bad as it is, alot of folks just can't bite their tongue.


Again, no disrespect.


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## tspence73 (Oct 14, 2008)

icehole said:


> Let the record also show that it's a very popular opinion.
> 
> 
> Spense, alot of people are upset when they see someone with genuine interest and enough money allow poor perspective, philosophy, and pride to stand in the way of efficiency and accomplishment -especially when they're in dire need of help.
> ...


Where in my philosophy or equipment choices have I been wrong here? Just curious. This system I'm building is going to be very good. If I were not learning anything or applying incorrect principles then the system would not sound good. Correct? I would say people are still mis-characterizing me and letting popularity (or lack thereof) override the facts. I have learned quite a bit in the last 3-4 months about car audio and learning more by the day with proper research. Soon, that research will go into testing and tweaking. We'll see where this all goes in the next year. Phase 1 (basic equipment/foundation) is nearly complete. Phase 2 is the acoustics/treatment phase in February. I'm likely going to use Second Skin products to treat my car starting with the trunk and door panels.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> Where in my philosophy or equipment choices have I been wrong here? Just curious. This system I'm building is going to be very good. If I were not learning anything or applying incorrect principles then the system would not sound good. Correct? I would say people are still mis-characterizing me and letting popularity (or lack thereof) override the facts. I have learned quite a bit in the last 3-4 months about car audio and learning more by the day with proper research. Soon, that research will go into testing and tweaking. We'll see where this all goes in the next year. Phase 1 (basic equipment/foundation) is nearly complete. Phase 2 is the acoustics/treatment phase in February. I'm likely going to use Second Skin products to treat my car starting with the trunk and door panels.



There's alot of fault in your philosophy and perspective. I'm not going to go into details, but for starters:


You refuse to accept basic principles.

You refuse to accept the help you ask for.

You refuse to accept that you may be wrong and that everyone else may be right.

You consider non-factual statements factual just because you think they are.

You blindly believe marketing claims.

You merit useless specs.

You make positive claims based on limited negative proof.

You make positive claims based on your use of selective science and inaccurate tools and measurements.

You treat a pair of budget components like grandma's ashes.


The list goes on...




Again, no disrespect. But you've got to understand that the one thing in common with all your problems is you.


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## tspence73 (Oct 14, 2008)

icehole said:


> There's alot of fault in your philosophy and perspective. I'm not going to go into details, but for starters:
> 
> 
> You refuse to accept basic principles.
> ...


Examples of the above would be a good idea before making statements. I've asked for examples before and have received none from you, so again, your statements are empty.



> You make positive claims based on your use of selective science and inaccurate tools and measurements.


If you're talking about the DMM thread, I was actually in the right. My careful usage of it and clarification of how I used it to obtain my results were sound and reasoned. 




> You treat a pair of budget components like grandma's ashes.


The blind test I used to select them didn't lie. I enjoy listening to them and haven't heard any others which would make me want to change. So, there ya go. 




> Again, no disrespect. But you've got to understand that the one thing in common with all your problems is you.


I have no problem. My system is not only going to meet my goals but likely exceed them and very likely be tweaked and tuned better than yours by the time I'm done. I never claimed to know everything, but will debate when anyone presents inaccurate info or leaves too much 'gray area' on the table as to be unclear.


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## slvrtsunami (Apr 18, 2008)

Thanks icehole, that is exactly the reason why I posted the post. I was really hoping you would kind of understand, eventually, what happens with majority of your posts. The same thing. OK, Im done, I know, I had no interest to begin with.

One last thing before I unsubscribe. I, as well as others, feel that the foundation should FIRST be sound deadening and THEN equipment. This way you will have a more accurate impression and feeling for the equipment you chose. Thanks again for taking the time to read. Hey Icehole, owe you a beer.


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## Knobby Digital (Aug 17, 2008)

All you've gotta do is re-read all your posts with an open mind and you'll see every example in detail.

I'm not gonna dig through all that mess, sorry.


And regarding your speakers, -I'm sure everyone likes their speakers -that's why they bought them. But that's not to say that they don't accept that they have limitations.

I'm not afraid of upgrading any component of my system, but I would like to know that I've seen at least close to its full potential before doing so. I think that's pretty common among most DIY types, and is why it's suggested to buy some at least decent processing early on.




slvrtsunami said:


> Hey Icehole, owe you a beer.


I'll take you up on that. My moms just moved to Seal Beach.


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## tspence73 (Oct 14, 2008)

slvrtsunami said:


> Thanks icehole, that is exactly the reason why I posted the post. I was really hoping you would kind of understand, eventually, what happens with majority of your posts. The same thing. OK, Im done, I know, I had no interest to begin with.
> 
> One last thing before I unsubscribe. I, as well as others, feel that the foundation should FIRST be sound deadening and THEN equipment. This way you will have a more accurate impression and feeling for the equipment you chose. Thanks again for taking the time to read. Hey Icehole, owe you a beer.


The whole purpose of deadening is to quell vibrations and noises. Each system will drive noises differently. This is WHY I'm buying the equipment first, then finding what is rattling/vibrating and treating the car accordingly. So, while you would start with damping for vibrations that don't exist yet and then find out later after you buy equipment you need to do more work, I will be treating the problems directly and have a proper way of knowing whether my efforts are working. I think the logic is pretty clear.


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## falkenbd (Aug 16, 2008)

How much did you spend on your JL midbass? Why did you buy them? 

HINT - you bought them because your infinity comps weren't good enough - period.

Sure your comps sounds good when you compare them to: 1 - all the speakers at walmart 2 - all the speakers at BB and CC

If you would have looked for a different set you could have avoided
1. Spending all that money on JL 8" midbass
2. Doing or paying for all of the work to get the midbass in your doors and a set of kick panels


BOTTOM LINE: If you weren't so stuck on those components, you could have achieved better quality without spending so much.


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## tspence73 (Oct 14, 2008)

falkenbd said:


> How much did you spend on your JL midbass? Why did you buy them?
> 
> HINT - you bought them because your infinity comps weren't good enough - period.
> 
> ...


This is all a matter of opinion. When I hear a set of comps that sound better on mids and highs, I'll switch. Until then I'm staying with what I've got. In my opinion, the Infinity Ref comps blew away the others I could audition head to head and compare. So, I made the choices I made and I don't think they are poor choices because I'm very likely to be happy with them when I'm done tuning it all up.


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## tspence73 (Oct 14, 2008)

Autiophile said:


> Efforts to change his mind on the comps are probably futile. If you want to help him with the stuff he's chose, by all means reply with some guidance but I think he's heard the point you all are trying to make. No one is helped by berating him about his choices again and again. It's been said. He feels differently. I don't think anyone here can do anything about his strategy, no matter how much you may disagree.
> 
> Let his results teach him the real world lessons.


Thank for understanding. I agree.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> Examples of the above would be a good idea before making statements. I've asked for examples before and have received none from you, so again, your statements are empty.



Examples, you really want examples? Here's one (from CAF):



Jimi77 said:


> 10-21-2008, 10:51 PM
> 
> Your subwoofer bass problem is being caused by some sort of cancellation trap, try moving or reorienting the woofer. Generally as far back in the trunk as possible and facing the rear, but you may have to experiement. I'd definately try pulling the 6x9s and their baffle and try upfiring the sub thru the rear deck.


That response is from your CAF "6x9 enclosure" thread. It went on for another 2 weeks and 3 pages, and you still didn't listen. And here we are 2 months later and still having the same discussion. In you 6x9 thread here I recommended a bandpass or IB. So what did you do? None of the above.... 

Would you like me to hunt down your ridiculous claims that Infinity Ref comps are good down to 60hz? Would you like to me to hunt down your claims that Infinity Ref comps are great because Infinity said so? Icehole was 110% correct and everybody but you can see it. 

I don't know why bothered posting the Eddie Runner links; I guess I like wasting my time. I could see you rejecting our advice if you actually had some experience or skills, but you can't even stop a door panel from vibrating due the massive midbass output of your Infinity Refs, which are so lacking in midbass output that you're relegating them to midrange only duty. Have fun reinventing the wheel.


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> Examples, you really want examples? Here's one (from CAF):
> 
> 
> 
> That response is from your CAF "6x9 enclosure" thread. It went on for another 2 weeks and 3 pages, and you still didn't listen. And here we are 2 months later and still having the same discussion. In you 6x9 thread here I recommended a bandpass or IB. So what did you do? None of the above....


I didn't want to do an IB setup. So I didn't. I didn't move the sub to the back of the trunk because there wasn't a link given like the one in this thread TO PROOF! You know, the strongest explanation you can give is by showing proof. It works. I don't just take someone's word for it. Sorry. 



> Would you like me to hunt down your ridiculous claims that Infinity Ref comps are good down to 60hz?


If I run with a 90-watts RMS amp, I can do a 24db/octave crossover at 60Hz and it should be fine. Now you're going to say "but you said it won't work as a midbass below 100Hz". That's right. AT 175-watts! Dufus. Now take that.



> Would you like to me to hunt down your claims that Infinity Ref comps are great because Infinity said so? Icehole was 110% correct and everybody but you can see it.


I never said the Ref comps sound good because Infinity said so. It's because 'I' said so based on listening tests I did MYSELF jerkface. Are you still trying to twist my words into something I didn't say nor intended? Just get lost man. Seriously, you're an idiot. I posted a link to Infinity's own videos on their testing methodology and how they develop speakers as a way of showing that they CAN develop great sounding speakers. I NEVER said my Infinity Reference comps sound good because "Infinity said so". So, go hunt and link it up. Show us all these claims you make about what I said. 

Go ahead and hunt down what I said. My test results showed the Reference Comp CAN do 60Hz up to around 100db SPL. That's pretty loud. When it gets up over 100db I start to hear driver distortion. My goals are to have NO distortion for up to 110-115db. So, go dig. Stop being an ass.



> I don't know why bothered posting the Eddie Runner links; I guess I like wasting my time. I could see you rejecting our advice if you actually had some experience or skills...


The links actually were good. You provided PROOF and that certainly goes a long way with me. That's all I ever ask. Don't just run your mouth. Link up something that shows what you're talking about. Do you know how many silly myths exist on the web when it comes to audio? I would like to try the advice. One problem. Scooting the subs to the back of the trunk will block the entire trunk from being used for anything other than holding the subs. Not good. Wouldn't switching phase help?


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> I would like to try the advice. One problem. Scooting the subs to the back of the trunk will block the entire trunk from being used for anything other than holding the subs. Not good. Wouldn't switching phase help?


Why not just try it to see if you like it before worrying about it.

In my current car, I've tried the box all over the trunk facing all different ways, and it's the same in the front of the trunk as that back so long as the subs face back so I keep it against the seats, but I don't have rear speakers. No matter where it's placed, you should at least have velcro on the bottom of the box to keep it from sliding around. If you like it all the way in the back of the trunk, just leave it like that until you need the space, then move it forward.


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## capnxtreme (Feb 5, 2008)

tspence73 said:


> If I run with a 90-watts RMS amp, I can do a 24db/octave crossover at 60Hz and it should be fine. Now you're going to say "but you said it won't work as a midbass below 100Hz". That's right. AT 175-watts! Dufus. Now take that.


OK, OK, OK... how old are you, seriously?


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## shadowfactory (Oct 20, 2008)

Dude just look at his icon to asses his mental abilities.


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## tspence73 (Oct 14, 2008)

icehole said:


> Why not just try it to see if you like it before worrying about it.
> 
> In my current car, I've tried the box all over the trunk facing all different ways, and it's the same in the front of the trunk as that back so long as the subs face back so I keep it against the seats, but I don't have rear speakers. No matter where it's placed, you should at least have velcro on the bottom of the box to keep it from sliding around. If you like it all the way in the back of the trunk, just leave it like that until you need the space, then move it forward.


Okay, I will give it a try. Actually, I have velcro that I bought specifically for the box, but the sub box is so heavy, it doesn't move at all. I weighs around 65-67 pounds.


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## Rudeboy (Oct 16, 2005)

slvrtsunami said:


> One last thing before I unsubscribe. I, as well as others, feel that the foundation should FIRST be sound deadening and THEN equipment. This way you will have a more accurate impression and feeling for the equipment you chose. Thanks again for taking the time to read. Hey Icehole, owe you a beer.





tspence73 said:


> The whole purpose of deadening is to quell vibrations and noises. Each system will drive noises differently. This is WHY I'm buying the equipment first, then finding what is rattling/vibrating and treating the car accordingly. So, while you would start with damping for vibrations that don't exist yet and then find out later after you buy equipment you need to do more work, I will be treating the problems directly and have a proper way of knowing whether my efforts are working. I think the logic is pretty clear.





tspence73 said:


> Hey all,
> 
> In my future plans for my car. Reducing driving noise is a big factor in getting the highest quality from my system.
> ...
> I will be doing 17" wheel eventually on my *Sentra*


This just gets stranger with time. Now you are contradicting yourself in both specifics and professed theoretical underpinnings. For someone who has spent SO much time "researching" to determine the most efficient route to your goals, this just doesn't make any sense. Based on the post I quoted from your sound deadening thread, you were doing better at the beginning of your journey.

We're talking about a Sentra here. The noise floor issues are completely predictable. Unless you will only be listening to this masterpiece parked with the engine off, your most recent conclusion that the only problem is noise and vibration introduced by your system isn't logical at all. All of your posts about driver efficiency and carefully matched output are even more absurd if you have to overcome a very noisy environment before you can even hear your new toys. Your new found clarity on the topic is akin to building a house so you can weigh it before you build the foundation, just so you will know how much weight it will have to support. Now you have to gut the vehicle again and work behind your wiring and installation to do what would have been much easier beforehand. Proper treatment of an economy car requires enough modifications that you may find your installation design doesn't work anymore.

It's actually more usual than not to approach things the way you have - install a sound system and then realize that it sounds like crap because of the noise floor. That's what gets most people involved with sound deadening in the first place. On the other hand, most people don't brag about the logic and integrity of the process that brought them there. For most, it is a "doh" moment. It seems like you do what you want, despite all of the advice you have asked for and received and then define what you are doing as logical, regardless of the evidence to the contrary.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> I didn't want to do an IB setup. So I didn't. I didn't move the sub to the back of the trunk because there wasn't a link given like the one in this thread TO PROOF! You know, the strongest explanation you can give is by showing proof. It works. I don't just take someone's word for it. Sorry.


Yeah, whatever you say. Of course you don't want to do an IB, you just want to come on here and moan and groan about your FR problems and then ignore any and all advice about how to fix it. 




tspence said:


> If I run with a 90-watts RMS amp, I can do a 24db/octave crossover at 60Hz and it should be fine. Now you're going to say "but you said it won't work as a midbass below 100Hz". That's right. AT 175-watts! Dufus. Now take that.


Oh, they're fine at 90rms but not at 2x their thermal rating. Unfortunately for you, alot of people have owned and/or heard the Infinity Refs, myself included.



tspence said:


> I never said the Ref comps sound good because Infinity said so. It's because 'I' said so based on listening tests I did MYSELF jerkface. Are you still trying to twist my words into something I didn't say nor intended? Just get lost man. Seriously, you're an idiot. I posted a link to Infinity's own videos on their testing methodology and how they develop speakers as a way of showing that they CAN develop great sounding speakers. I NEVER said my Infinity Reference comps sound good because "Infinity said so". So, go hunt and link it up. Show us all these claims you make about what I said.


I can link to the thread on CAF where you bought Infinity's marketing claims hook, line and sinker. 




tspence said:


> Go ahead and hunt down what I said. My test results showed the Reference Comp CAN do 60Hz up to around 100db SPL. That's pretty loud. When it gets up over 100db I start to hear driver distortion. My goals are to have NO distortion for up to 110-115db. So, go dig. Stop being an ass.


LOL, I wonder how you determined this considering you door panel supposedly resonates in that frequency range. 



tspence said:


> The links actually were good. You provided PROOF and that certainly goes a long way with me. That's all I ever ask. Don't just run your mouth. Link up something that shows what you're talking about. Do you know how many silly myths exist on the web when it comes to audio? I would like to try the advice. One problem. Scooting the subs to the back of the trunk will block the entire trunk from being used for anything other than holding the subs. Not good. Wouldn't switching phase help?


LOL - yeah I'll make sure I do an exhaustive search of the internet *for you *everytime you have some sort of problem with *your system* just so I meet your PROOF pre-requist. I guess it's not enough that a dozen people all way more knowledbable than you about car audio are telling you the same thing. Appearently in all your testing, you still haven't figured out what phase does and clearly you didn't understand Eddie Runner's article if you think switching phase will help. You're hopeless.


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## Jimi77 (Jul 4, 2005)

Rudeboy said:


> This just gets stranger with time. Now you are contradicting yourself in both specifics and professed theoretical underpinnings. For someone who has spent SO much time "researching" to determine the most efficient route to your goals, this just doesn't make any sense. Based on the post I quoted from your sound deadening thread, you were doing better at the beginning of your journey.


Clearly he lacks an understanding of the basic principles and theories that the rest of accept and apply to the hobby. The tspence method is to throw out all the standard approaches to car audio and reinvent the wheel.


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## tspence73 (Oct 14, 2008)

Rudeboy said:


> This just gets stranger with time. Now you are contradicting yourself in both specifics and professed theoretical underpinnings. For someone who has spent SO much time "researching" to determine the most efficient route to your goals, this just doesn't make any sense. Based on the post I quoted from your sound deadening thread, you were doing better at the beginning of your journey.
> 
> We're talking about a Sentra here. The noise floor issues are completely predictable. Unless you will only be listening to this masterpiece parked with the engine off, your most recent conclusion that the only problem is noise and vibration introduced by your system isn't logical at all. All of your posts about driver efficiency and carefully matched output are even more absurd if you have to overcome a very noisy environment before you can even hear your new toys. Your new found clarity on the topic is akin to building a house so you can weigh it before you build the foundation, just so you will know how much weight it will have to support. Now you have to gut the vehicle again and work behind your wiring and installation to do what would have been much easier beforehand. Proper treatment of an economy car requires enough modifications that you may find your installation design doesn't work anymore.
> 
> It's actually more usual than not to approach things the way you have - install a sound system and then realize that it sounds like crap because of the noise floor. That's what gets most people involved with sound deadening in the first place. On the other hand, most people don't brag about the logic and integrity of the process that brought them there. For most, it is a "doh" moment. It seems like you do what you want, despite all of the advice you have asked for and received and then define what you are doing as logical, regardless of the evidence to the contrary.


I think buying the equipment FIRST and then applying damping materials make perfect sense. You didn't explain how it works better the other way. It won't. You can't fix vibrations and buzzes that don't exist yet. So, if you have found way to reason it out opposite to that logic, cheers. I won't bother arguing with you on this topic. It's pointless.


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> Yeah, whatever you say. Of course you don't want to do an IB, you just want to come on here and moan and groan about your FR problems and then ignore any and all advice about how to fix it.


There is more than one way to design a sound system. I didn't choose to do it this way. 



> Oh, they're fine at 90rms but not at 2x their thermal rating. Unfortunately for you, alot of people have owned and/or heard the Infinity Refs, myself included.


Obviously you don't know how to tune them or EQ them properly for your car. Either that or we just have different preferences in sound. 



> I can link to the thread on CAF where you bought Infinity's marketing claims hook, line and sinker.


The marketing claims that Infinity made are backed up by science and a pretty good speaker evaluation method. I don't "buy" anybody's marketing but what Infinity showed wasn't just a piece of "marketing" they showed how they evaluate speakers. It's a pretty good method in my opinion and that's not "buying" into someone's marketing. If I did, then why would I buy the Reference series instead of the Perfect series? I bought the Reference series because that's what MY ears told me sound best in a BLIND test. But, as you say, I "buy" their marketing "hook, line and sinker". No, you are a turd and still trying to twist my words around her like you did in the other forum. 



> LOL, I wonder how you determined this considering you door panel supposedly resonates in that frequency range.


Because the driver distortion is a DIFFERENT SOUND than the door panel and is audible WHEN REMOVED from the door. I made sure about what sounds I was hearing and where they came from. 



> LOL - yeah I'll make sure I do an exhaustive search of the internet *for you *everytime you have some sort of problem with *your system* just so I meet your PROOF pre-requist. I guess it's not enough that a dozen people all way more knowledbable than you about car audio are telling you the same thing. Appearently in all your testing, you still haven't figured out what phase does and clearly you didn't understand Eddie Runner's article if you think switching phase will help. You're hopeless.


No, not hopeless. Just still learning. I'm not an audio engineer, so you can't possibly expect me to understand every principle and how it applies to other audio problems/concepts. That's why I ASKED if a phase adjustment would work. I didn't state that it would. Again, you are twisting my words and meaning. You took my QUESTION and read it as a statement. WRONG. BUZZ. You are an idiot. And I'm not so sure you are the expert you say you are. I trust Chad on here, but not many others. I won't just believe something someone says just because they say something is so. If asking for proof gets you attacked, then attack me. I want proof. An explanation. Some thread of logic. Not just, "well because I said".


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## MarkZ (Dec 5, 2005)

I know I don't visit this board as much as I used to, so apparently I'm out of the loop. But why has tspence become everybody's whipping boy? Just because somebody asks for input and ideas doesn't mean that they have to implement them. What am I missing?


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## Rudeboy (Oct 16, 2005)

MarkZ said:


> I know I don't visit this board as much as I used to, so apparently I'm out of the loop. But why has tspence become everybody's whipping boy? Just because somebody asks for input and ideas doesn't mean that they have to implement them. What am I missing?


tspence is a special case. Search on the threads he has started or just browse through the "You Should Have Searched First" sub-forum. He likes to ask for advice and then explain why it is all wrong.


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## Rudeboy (Oct 16, 2005)

tspence73 said:


> I think buying the equipment FIRST and then applying damping materials make perfect sense. You didn't explain how it works better the other way. It won't. You can't fix vibrations and buzzes that don't exist yet. So, if you have found way to reason it out opposite to that logic, cheers. I won't bother arguing with you on this topic. It's pointless.


If all you are concerned with is resonance introduced by your new equipment, you would be right, but if all you are concerned with is resonance introduced by your new equipment, your car will never sound good. Most noise sources have nothing to do with the added power - they were present before you started swapping things out. You were on the right track when you started a thread about lowering the noise floor as an important first step. 

It makes sense to address this first - especially since you were aware of the problem before you did anything else - because it's easier to strip the car once, apply vibration dampers, barriers, etc. and lay out your wiring. Now you'll have to do it again. That's all. It isn't a big deal, since most people follow that path, but most people don't brag about the "logic" they used to get there.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> Obviously you don't know how to tune them or EQ them properly for your car.


Isn't the only EQ you use the HU?



tspence73 said:


> If asking for proof gets you attacked, then attack me. I want proof. An explanation. Some thread of logic. Not just, "well because I said".


You don't need to be an EE to learn from experience (or even the internet), and not everyone can explain in scientific detail why everything works well or sounds good, even an EE. I posted earlier on, non-offensively, many of the reasons why people attack you. But like everything else told to you, you didn't seem to understand that either.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> There is more than one way to design a sound system. I didn't choose to do it this way.



He chose to make his system








instead.


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> He chose to make his system
> 
> 
> 
> ...


Damn right and don't you forget it!


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## tspence73 (Oct 14, 2008)

icehole said:


> Isn't the only EQ you use the HU?


Yes, but there is also a -3db option on the crossover that comes with these comps. I'll bet you haven't heard the comps. Most likely the coax. Which are still nice BTW but can't take nearly the pounding (much lower power rating).


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## Knobby Digital (Aug 17, 2008)

posting while doing Caltrans owns me


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> Yes, but there is also a -3db option on the crossover that comes with these comps. I'll bet you haven't heard the comps. Most likely the coax. Which are still nice BTW but can't take nearly the pounding (much lower power rating).


I've been to Fry's Electronics before.

And you're kidding about that tweeter att on the passive, right?


I think you misunderstood the g-ma's ashes comment. I stopped clowning your speakers a while back, and suggested you try the same thing 1 or 2 sizes down to ease installation. It's your approach to them I was referring to. They're a set of budget speakers. Why not try them active? Why not look beyond them? Experiment, man. This is the meat and potatoes of your system. 

I understand if you've not heard anything better, but at the same time how did you come to decide on those JLs you just bought?


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## tspence73 (Oct 14, 2008)

icehole said:


> I've been to Fry's Electronics before.
> 
> I think you misunderstood the g-ma's ashes comment. I stopped clowning your speakers a while back, and suggested you try the same thing 1 or 2 sizes down to ease installation. It's your approach to them I was referring to. They're a set of budget speakers. Why not try them active? Why not look beyond them? Experiment, man. This is the meat and potatoes of your system.
> 
> ...


I've found that choosing speakers for playing the bass range is pretty easy. Most drivers that spec out can produce great bass sound. Mids and highs are a completely different story. Specs don't tell the whole story. Something could look better on paper but sound worse than a set whose's numbers aren't as good. With that range I will always trust my ear over specs. Even if it seems stupid to others. I won't compromise on that. 

I have two amps installed and they are hidden away under the front seats. To go completely active I will need at least another amp. I haven't come up with any way of keeping that hidden (yet). When I do, I will very likely go completely active on the comps.

One thing about ditching the passive crossover that comes with the set though. From what I've read, the passive xover can add a little something to the sound. A certain character to it's phase or dispersion of frequencies. Would I be altering the sound by going active and possibly changing the very thing that might be making a difference in the sound (ie will I think it sounds the same)? That's specifically why I didn't downsize the comp woofer, even though it will be moved to midrange duty. Because a different size driver = different sound character. I'm also hesitant to change the xover. 

As Gary Bussey's daddy used to say, "if somethin' ain't broke don't fix it". And "when you want to put a nail in the wood, don't do anything fancy, just get a hammer and pound the son of a bitcb until it's in.".


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> As Gary Bussey's daddy used to say, "if somethin' ain't broke don't fix it". And "when you want to put a nail in the wood, don't do anything fancy, just get a hammer and pound the son of a bitcb until it's in.".


Why the f*** did you put please critique in the title of this thread if you are going to ignore all critiques you get and type long winded boring paragraphs about why you aren't going to try anything new or experiment in any way? I just think you are scared of trying new things. It takes balls to experiment, now go prove you have some.


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## Rudeboy (Oct 16, 2005)

tspence73 said:


> I've found that choosing speakers for playing the bass range is pretty easy. Most drivers that spec out can produce great bass sound. Mids and highs are a completely different story. Specs don't tell the whole story. Something could look better on paper but sound worse than a set whose's numbers aren't as good. With that range I will always trust my ear over specs. Even if it seems stupid to others. I won't compromise on that.
> 
> One thing about ditching the passive crossover that comes with the set though. From what I've read, the passive xover can add a little something to the sound. A certain character to it's phase or dispersion of frequencies. Would I be altering the sound by going active and possibly changing the very thing that might be making a difference in the sound (ie will I think it sounds the same)? That's specifically why I didn't downsize the comp woofer, even though it will be moved to midrange duty. Because a different size driver = different sound character. I'm also hesitant to change the xover.


Sweet Jesus - 154 posts in this thread alone, months of threads on every conceivable topic and this is where you are. I'm starting to agree with whoever suggested this is another member goofing on us


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## Oliver (Jun 25, 2007)




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## Jimi77 (Jul 4, 2005)

Rudeboy, you may be right, this probably is some sort of joke. Seriously how could anybody be this confused and ignorant about car audio, yet at the same time be so brash and arrogant?

Have you lost you mind spence? You're going to question my EQing skills? I'm not the one the giant hole in my frequency response asking bone headed questions and spinning my wheels trying to fix the issues with my system. Seriously there probably isn't a member on this board less knowledgable about car audio than you, so anybody's advice offered here should be accepted without a pre-requisit for some sort of scientific proof.

BTW, we were turning our subs around and finding other ways to use reflections to increase output long before Eddie Runner posted his experiment on the internet... hell before there even was an internet.


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## Oliver (Jun 25, 2007)

Jimi77 said:


> Rudeboy,is right, hell before there even was an internet people new how to set up systems


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> I've found that...


It's clear that everything you do has _some sort_ of purpose.

But did it ever occur to you that, by asking for advice, and then arguing with the people who are more experienced and knowledgeable that give you advice, and then doing the exact *opposite* ensures that you'll be taking the least efficient route to meet your goals?


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## tspence73 (Oct 14, 2008)

All I've argued is that I'm keeping my comps the way they are. So it's time for you fools to STFU already.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> All I've argued is that I'm keeping my comps the way they are. So it's time for you fools to STFU already.


You get into an argument every single time you ask for advice.


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## tspence73 (Oct 14, 2008)

icehole said:


> You get into an argument every single time you ask for advice.


I think it's because some wish to try and force someone to their way of thinking rather than just let it be. If there is something wrong I will eventually find it and come full circle to trying it your way. If there isn't anything wrong and it's great then we all have nothing to worry about. Just chill.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> I think it's because some wish to try and force someone to their way of thinking rather than just let it be. If there is something wrong I will eventually find it and come full circle to trying it your way. If there isn't anything wrong and it's great then we all have nothing to worry about. Just chill.


Then why ask for advice?


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## tspence73 (Oct 14, 2008)

icehole said:


> Then why ask for advice?


I don't recall asking for advice for the comps.


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## Knobby Digital (Aug 17, 2008)

I'm speaking in general.

But, this is how your speakers came up:



tspence73 said:


> Where in my philosophy or equipment choices have I been wrong here? Just curious.


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## tspence73 (Oct 14, 2008)

icehole said:


> I'm speaking in general.
> 
> But, this is how your speakers came up:


I asked what was wrong with my choices. There is nothing wrong with keeping a perfectly good sounding set of comps on their intended passive crossovers. It's a viable choice to keep the passive portion of this 4-way system. It's certainly possible that changing the comps to an active crossover could alter it's signature sound or change it enough that I might not have the same enjoyment. It's certainly possible also that it could slightly improve the sound. But when they sound as good as I could ever want them to, and I have zero problem with how it sounds, it's probably then best to leave it as is and not change it.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> I asked what was wrong with my choices.


So you got an answer.


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## Knobby Digital (Aug 17, 2008)

But back to the question, why ask for advice if your mind is made up already?


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## Jimi77 (Jul 4, 2005)

icehole said:


> But back to the question, why ask for advice if your mind is made up already?


Asking so he knows how it should be done, so he can do something different.... Maybe he thinks the laws of physics operate differently in his corner of the world....


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## Knobby Digital (Aug 17, 2008)

Jimi77 said:


> Asking so he knows how it should be done, so he can do something different.... Maybe he thinks the laws of physics operate differently in his corner of the world....


Funny that I just asked him that 2 posts above, and without answering he posts this:




tspence73 said:


> I asked what was wrong with my choices. There is nothing wrong


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> But when they sound as good as I could ever want them to, and I have zero problem with how it sounds, it's probably then best to leave it as is and not change it.


And this sentence perfectly demonstrates why you have no balls.


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> And this sentence perfectly demonstrates why you have no balls.


What is the point though? I knew there was a problem with the midbass section, so I came up with a good solution. I found I was clipping my amp to my subs. So I upgraded the subs and now have 0 clipping and improved bass. I have found viable solutions for audible problems.

I appreciate suggestions and consider them and add them to my memory and later on there may be things I'll try. For now I've made choices that fit what I want for the time being. Perhaps later on I'll hear someone else's system and be impressed enough with their mid/hi range to think about changing. So far that hasn't happened. I have to say most people's systems I've heard are badly distorting, and setup very poorly with no attention to acoustic treatment. 

The only systems I would consider a "hi-fidelity" type sound is luxury cars who's stock systems sound good. Virtually all aftermarket systems I've heard around do not qualify as properly set, or balanced, or having low distortion, or no clipping. 

When I hear a high-output capable system that is set properly and I can truly judge it's overall sound properly, then I can compare the mid/hi range better.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> The only systems I would consider a "hi-fidelity" type sound is luxury cars who's stock systems sound good. Virtually all aftermarket systems I've heard around do not qualify as properly set, or balanced, or having low distortion, or no clipping.


That's one of the most ass backwards statements I have ever read. 

You must have heard some god awful aftermarket installs then. Even 'luxury' cars' audio systems are the last step in the design process, as the car maker doesn't really care. Ever opened a car door? Ever seen one designed to be a good speaker enclosure? HELL NO. Car makers don't give a good flying **** about SQ and never have. The reason why? Most consumers just don't care. And the ones that do rip out the ****ty factory setup and replace it with real speakers.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> I found I was clipping my amp to my subs. So I upgraded the subs and now have 0 clipping and improved bass. I have found viable solutions for audible problems.


Uhhhhhhhhhhhhhhhh
You can fix clipping with the ****ing gain knob...................


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> Uhhhhhhhhhhhhhhhh
> You can fix clipping with the ****ing gain knob...................


Come on now. The 10" sub when set to 0 clipping simply did NOT deliver enough SPL for even a "low" output system. I was totally unsatisfied with the SPL of 0 clipping with the 10" sub I was running and I'm no basshead. The system with my subwoofer upgrade now has sufficient bass with no clipping at all. I now have what I would consider a MINIMUM SPL output for a hi end system in the low bass region. I only wish I had an amp that could deliver 1,200 watts at 4-ohms to get a bit more bite to the low end but it's not at all bad at 1-ohm. For now I will go with it. Later on I will probably upgrade the sub amp so I can drive 1,200-watts RMS @ 4-ohms. For now I have a good MINIMUM standard. Remember, this is with sealed enclosures meant for flat bass response, not the loaded SPL ported type enclosures.


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> That's one of the most ass backwards statements I have ever read.
> 
> You must have heard some god awful aftermarket installs then.


I think the VAST majority of car audio systems are clipping to an extreme and are designed and set for loudness, not quality. So, I'm still trying to encounter someone in person who's system I can listen to who has setup his gear for smooth, quality sound and still has generous output. My system very soon should have these qualities and I can't wait to get phase 1 out of the way.



> Even 'luxury' cars' audio systems are the last step in the design process, as the car maker doesn't really care. Ever opened a car door? Ever seen one designed to be a good speaker enclosure? HELL NO. Car makers don't give a good flying **** about SQ and never have. The reason why? Most consumers just don't care. And the ones that do rip out the ****ty factory setup and replace it with real speakers.


Luxury vehicles have generally quiet cabins and I think that is one of the main reasons why their stock systems sound pretty darn good. Phase 2 in February should address cabin noise and damp vibration-borne panel distortions. I only hope I have enough money to address all the audible issues I'm likely to have when phase 1 is complete.

At this time at 70 mph on the freeway, my cabin encounters high 80'sdb/low 90's of road/wind/traffic noise as measured on my SPL meter. I'm hoping to take that down to the 70's.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> I think the VAST majority of car audio systems are clipping to an extreme and are designed and set for loudness, not quality.


Be that as it may, it does not change the fact that most factory setups suck balls as well. 



tspence73 said:


> Luxury vehicles have generally quiet cabins and I think that is one of the main reasons why their stock systems sound pretty darn good.


That has absolutely nothing to do with the stock system and everything to do with the factory deadening. So by your logic any properly deadened car (like mine) sounds good by default? That doesn't really make sense, its like saying any speaker used in a home environment sounds good because a house is quiet... sure noise floor is important but that does not make any system good, all it lets you do is hear whats already there.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> The 10" sub when set to 0 clipping simply did NOT deliver enough SPL for even a "low" output system. I was totally unsatisfied with the SPL of 0 clipping with the 10" sub I was running and I'm no basshead. The system with my subwoofer upgrade now has sufficient bass with no clipping at all.


No **** sherlock you went from a _craptacular _ pioneer low power 10" sub to two 12's... how could you *not* see an improvement in "SPL" from that? And why in the world would you think a single dinky pioneer sub could give you "sufficient SPL"... it is what it is, no wonder you were clipping it so much you were trying to make it do something physically impossible. You can't get tons of output from a crappy single sealed 10". 

And how do you set something to '0' clipping, were you measuring the amount of clipping with the oscilloscope you don't have?


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> I only wish I had an amp that could deliver 1,200 watts at 4-ohms to get a bit more bite to the low end but it's not at all bad at 1-ohm. For now I will go with it.


Because, once again, you have no balls to try something new. Like wiring it to 4 ohms and hearing how much better it sounds while ignoring wattage rating numbers that are just that... RATINGS, *not* absolutes. 

I bet you 500 bucks you could only discern a minor difference in output, while gaining a huge upgrade in quality.

Seriously dude, if you want to continue in your strange audio quest you really need to start learning how to use your ears and not your calculator.


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> Be that as it may, it does not change the fact that most factory setups suck balls as well.
> 
> 
> 
> That has absolutely nothing to do with the stock system and everything to do with the factory deadening. So by your logic any properly deadened car (like mine) sounds good by default? That doesn't really make sense, its like saying any speaker used in a home environment sounds good because a house is quiet... sure noise floor is important but that does not make any system good, all it lets you do is hear whats already there.


Have you ever heard a factory Bose system in a luxury car? It's actually pretty good. Even if Bose home audio blows, their factory auto system sounds good. There are stock systems in luxury cars that sound quite good. I don't know what luxury cars you've been listening to.


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> No **** sherlock you went from a _craptacular _ pioneer low power 10" sub to two 12's... how could you *not* see an improvement in "SPL" from that? And why in the world would you think a single dinky pioneer sub could give you "sufficient SPL"... it is what it is, no wonder you were clipping it so much you were trying to make it do something physically impossible. You can't get tons of output from a crappy single sealed 10".
> 
> And how do you set something to '0' clipping, were you measuring the amount of clipping with the oscilloscope you don't have?


There are people who run 10's and get good output because they run large enclosures or dual 10's. I found a sealed 10" wasn't enough. I actually went on a recommendation from a "so called" expert on another forum, so you can understand now why I'm skeptical and think anyone can be false. Just like you. First you criticize me for clipping the amp to get proper output, then when I explain WHY you jump out and say "no ****"? You're an idiot. Just shut up already you moron. I'm tired of your drivel.


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> Because, once again, you have no balls to try something new. Like wiring it to 4 ohms and hearing how much better it sounds while ignoring wattage rating numbers that are just that... RATINGS, *not* absolutes.
> 
> I bet you 500 bucks you could only discern a minor difference in output, while gaining a huge upgrade in quality.
> 
> Seriously dude, if you want to continue in your strange audio quest you really need to start learning how to use your ears and not your calculator.


Again, you show yourself to be stupid. By going down from 1,200 RMS peak to 500 peak that is a loss of 4db. That is an audible loss of output when the 1,200-watt RMS peak is BARELY making what I consider a MINIMUM output for a sound quality system. I'm not going to go back to clipping my sub stage again. Sorry. When I want to go to 4-ohms, I will upgrade the amp.


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## Rudeboy (Oct 16, 2005)

tspence73 said:


> It's certainly possible that changing the comps to an active crossover could alter it's signature sound or change it enough that I might not have the same enjoyment.


What can a passive x-over contribute to a "signature sound" that is consistent with accurate reproduction? It's possible that a one-size-fits-all solution can sound as good as an active x-over - if your vehicle is a perfect match for the assumptions made when it is designed, but the odds are against you. How can it possibly be better? You need to hold yourself to the same standards for "proof" that you demand from everyone else.


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## cheesehead (Mar 20, 2007)

Rudeboy said:


> Sweet Jesus - 154 posts in this thread alone, months of threads on every conceivable topic and this is where you are. I'm starting to agree with whoever suggested this is another member goofing on us


Maybe so but just think what he has done for the viewership on this forum. This thread alone has over 1,900 views? Great for the sponsors!


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## 14642 (May 19, 2008)

shadowfactory said:


> You must have heard some god awful aftermarket installs then. Even 'luxury' cars' audio systems are the last step in the design process, as the car maker doesn't really care. Ever opened a car door? Ever seen one designed to be a good speaker enclosure? HELL NO. Car makers don't give a good flying **** about SQ and never have. The reason why? Most consumers just don't care. And the ones that do rip out the ****ty factory setup and replace it with real speakers.


1. Speakers don't require an enclosure. Baffle? Yes. Enclosure? No, especially when a high pass filter is used.

2. Car companies' desires for high-end branded audio systems refutes your suggestion that consumers don't care about the quality of the audio systems in their cars. Furthermore, plenty of studies about listening preferences suggest just the opposite of your statement. 

3. Granted, cars aren't often designed around the OE audio system, but that doesn't mean that a good system can't be implemented. 

4. Many OE audio systems are designed and tuned by audio engineers with doctoral degrees in their fields and include tuning tools that are much more sophisticated than anything available in the aftermarket. Do they always sound good? No. In many cases, the car companies' "audio" engineers have the final say in the tuning and they're rarely correct. 

5. Aftermarket consumers buy components and OE companies provide systems. Those are completely different propositions. Just because the OE speaker you may pull out of the door to install an aftermarket speaker doesn't have a nice sticker on the magnet or a plastic cup over the backplate, a $20,000 industrial design, binding post terminals and some kind of preposterously expensive cone material that's painted blue doesn't mean it isn't a good speaker, properly designed for its applictaion.

Although the underlying criterion for TSpence's design is of questionalble value (the idea that nothing should ever clip) and flies in the face of current professional research regarding the audibility of distortion, it's his criterion. If he has the money to provide 6 or 9dB more power than is required to meet his volume requirements without AUDIBLE distortion, then he ought not to be ridiculed. 

I find that the folks here who are quickest to become irate and to state their cases as offesively as they can are often the least knowledgeable and more often than not are providing incorrect information as forcefully as possible. 

I've listened to thousands of systems--aftermarket and OE. Do I know everything? No. Do I know more than the average bear? Yes. While there are plenty of OE systems that are awful, there are many more aftermarket systems, installed by "professionals" and DIYers alike that suck much harder than any step-up OE system. That's a shame, considering that many professional installers and DIYers prolcaim themselves to be knowledgeable enthusiasts and earn and spend money on top of what has already been spent on the OE gear. 

The following is not directed at Shadowfactory. Rather, it's a suggestion for everyone here who tunes in hoping to learn something and to share the benefit of their experiences:

The fact that one doesn't understand or agree with something doesn't necessarily mean that it ought to be ridiculed. Be careful. There are few things more stupid than asserting what you know in a way that suggests you no longer have anything to learn.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> The only systems I would consider a "hi-fidelity" type sound is luxury cars who's stock systems sound good. Virtually all aftermarket systems I've heard around do not qualify as properly set, or balanced, or having low distortion, or no clipping.


Finally. If you're looking for the sound of a "nice stock system," then don't waste you time with us. We're looking for a totally different sound - no holes in the FR, relatively flat FR, greater output, etc. 

At least it all makes sense now. I'd suggest you stop wasting time with us and go to a junk yard and strip a system out of a luxary car and install it in your Sentra.


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## tspence73 (Oct 14, 2008)

Rudeboy said:


> What can a passive x-over contribute to a "signature sound" that is consistent with accurate reproduction? It's possible that a one-size-fits-all solution can sound as good as an active x-over - if your vehicle is a perfect match for the assumptions made when it is designed, but the odds are against you. How can it possibly be better? You need to hold yourself to the same standards for "proof" that you demand from everyone else.


I would be willing to try a fully active system but maybe you can tell me where I can mount this extra amp out of sight?  Then I might consider this at some future time.


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> Finally. If you're looking for the sound of a "nice stock system," then don't waste you time with us. We're looking for a totally different sound - no holes in the FR, relatively flat FR, greater output, etc.
> 
> At least it all makes sense now. I'd suggest you stop wasting time with us and go to a junk yard and strip a system out of a luxary car and install it in your Sentra.


If you have not heard a good factory system from a luxury car then you are wasting your time posting in here. There are good factory stereos in some luxury cars my friend. Believe that.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> If you have not heard a good factory system from a luxury car then you are wasting your time posting in here. There are good factory stereos in some luxury cars my friend. Believe that.


Which ones in particular? The sound systems in all the Caddy's, BMW's, Jags, and Mercedes I've driven have been horrendous. I've begun to warm up to the stock system currently in my Volvo (not that I'd consider it a "luxury" car...). It took me a while because the imaging is AWFUL despite their use of a center channel presumably designed to enhance imaging. The FR is also pretty bad, but the midbass is surprisingly punchy and the output can get fairly high before clipping. I think there are different audio systems in Volvos that utilize the same head unit though, because I've seen different speaker configurations.

My dad's BMW has a logic7 setting, but sounds godawful tonally...



> Have you ever heard a factory Bose system in a luxury car? It's actually pretty good. Even if Bose home audio blows, their factory auto system sounds quite good. There are stock systems in luxury cars that sound quite good. I don't know what luxury cars you've been listening to.


The problems I had with the Bose systems in my last two Caddys were that the midbass was bloated and flat-sounding (mostly because I think they were trying to achieve "sub-bass" without actually doing it correctly...), the midrange was imbalanced tonally, and it clipped sooner than I would prefer for a "high end" system. There are far worse systems out there though.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> Have you ever heard a factory Bose system in a luxury car? It's actually pretty good. Even if Bose home audio blows, their factory auto system sounds quite good. There are stock systems in luxury cars that sound quite good. I don't know what luxury cars you've been listening to.



:lol: :lol: :lol: Infinity Refs are the best sounding comps and Bose systems sound quite good.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> If you have not heard a good factory system from a luxury car then you are wasting your time posting in here. There are good factory stereos in some luxury cars my friend. Believe that.



LOL - yeah, I'm the one wasting my time posting here. The only time I'm wasting my time on here is when I give you advice that I know will be rejected. Have fun reinventing the wheel.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> Again, you show yourself to be stupid. By going down from 1,200 RMS peak to 500 peak that is a loss of 4db. That is an audible loss of output when the 1,200-watt RMS peak is BARELY making what I consider a MINIMUM output for a sound quality system. I'm not going to go back to clipping my sub stage again. Sorry. When I want to go to 4-ohms, I will upgrade the amp.


Wait, "luxary" car audio systems sound good, but 1200rms is BARELY enough to make minimum output for a quality sound system.

Rudeboy, you're right, somebody is clowning us.


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## Jimi77 (Jul 4, 2005)

Andy Wehmeyer said:


> I've listened to thousands of systems--aftermarket and OE. Do I know everything? No. Do I know more than the average bear? Yes. While there are plenty of OE systems that are awful, there are many more aftermarket systems, installed by "professionals" and DIYers alike that suck much harder than any step-up OE system. That's a shame, considering that many professional installers and DIYers prolcaim themselves to be knowledgeable enthusiasts and earn and spend money on top of what has already been spent on the OE gear.



Do the DIY systems "suck harder" than an OE system or do they accomplish a different goal? They're just focused on different goals, usually loudness and therefore they don't care about clipping, their one note wonder enclosures, terrible FR, etc. They don't suck harder so much as suck differently.


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## Knobby Digital (Aug 17, 2008)

Andy Wehmeyer said:


> The fact that one doesn't understand or agree with something doesn't necessarily mean that it ought to be ridiculed.


For me personally, I'm not trying to force ideas into Spense. I think his biggest error is starting at the end of the signal chain and working up. I've given him a couple suggestions, and that's that. I have no real interest in the outcome of his system, but I do wish him success.


I'm honestly trying to get to the bottom of his psychology.

We've all thought something would work, and hoped it would, only to ask for verification and were advised to do something different. Most of us learned by doing and listening and re-doing.

If someone is asking for advice and they keep getting answers they don't like they usually do one of two things:

1. Take the advice

2. Don't take the advice, stop asking questions, and do what they had originally planned.

He has some kind of logical reason for everything. I really just want to know why he keeps doing neither, since he's getting nowhere.


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## 14642 (May 19, 2008)

Jimi77 said:


> Do the DIY systems "suck harder" than an OE system or do they accomplish a different goal? They're just focused on different goals, usually loudness and therefore they don't care about clipping, their one note wonder enclosures, terrible FR, etc. They don't suck harder so much as suck differently.


Hmmm...differently, but for me, quite a bit harder, on average. I rent lots of cars when I travel and I always try to get something I've never driven, mostly to see what the cars sound like. I'm rarely impressed, but I'm equally rarely disgusted. When I visit car audio retailers or attend audio competitions, I always ask to hear some cars and I'm rarely impressed, but I'm often disgusted. 

All step-oe systems have one performance target that's a requirement for them but is rarely considered for aftermarket--that all seats should sound similar. Everyone here knows the compromises that requires--they're often more than anyone cares to deal with.


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## Knobby Digital (Aug 17, 2008)

Jimi77 said:


> Bose systems sound quite good.


All ******** aside, a stock Bose sounds far better than an aftermarket Best Buy sytem *WITHOUT EQ.
*

But that's not what you should strive for. And if you've spent $500+ and you're not there, you're doing something TERRIBLY wrong.


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## 14642 (May 19, 2008)

That's what I'm getting at...thanks.


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> Wait, "luxary" car audio systems sound good, but 1200rms is BARELY enough to make minimum output for a quality sound system.
> 
> Rudeboy, you're right, somebody is clowning us.


Nobody is "clowning" you. 

When you take two RE SE 12's and put them in an ideal "sealed" enclosure and wire them up for 1-ohm, then you use a 50Hz 0db tone and your headunit at 75% of it's volume, then set the amp's speaker output with a DMM to 34.6 volts, you end up with a maximum peak output of 119db with a little additional cabin gain. 

Surprisingly, setting the amp this way results in an output that is what I consider "just about right". Certainly it's more bass than a system has that is set to a flat frequency response. But I like the depth deep bass seems to add to sound. IMO, it sounds more 'real' when there is a bit of additional deep bass. I have heard extremely loud bass systems and I can tell you that my system is not what I consider to be 'loud' bass. I would say my system sounds like it has what sounds like a tasteful 'bass boost' effect (when compared to most other stock systems). 

I've come to the conslusion that clean sound output with 0 clipping (in the bass region) requires quite a bit of power output capability from the car's electrical as well as from the amp as well as a decent amount of efficiency from the subs. Heck, the very power source of the car feeding the audio system can limit impact and quality of bass. Bass frequencies seem to be the most difficult area for car systems to produce cleanly and accurately. And I'm not even talking about "boom boom boom" type rap systems. I'm talking about a system that has a slight dash of 'spice' and impact in the bass at the lowest frequencies and be able to remain unclipped. Remember, this is a well defined opinion formed from testing and testing some more. 

Let me put it this way. A car audio shop that is about to make a set of custom kicks for me to my specs, when they looked at my sub amp and subs, they thought it was going to be 'way loud man'. Then when I showed them how it really sounded, all they could say was how 'we can make it louder man'. I told them that my goals were for quality, not SPL and then they started to listen to it with another perspective. They still thought the bass was a tad on the 'light' side for how much power I have going to two 12's. I consider the bass to be very accurate and it has the capability to output up to 119db or more at 0db bass frequency peaks. The 'average' sound output is really around 90db - 105db (which is still plenty loud but not 'basshead' loud).

I actually like the idea of modeling my setup around the concept of a THX rated theater system. I only wish music studios recorded, mixed and mastered their recordings around a 75db reference white noise tone like movie studios do. It's sad when movie soundtracks have a set standard of sound reproduction that home users can easily emulate to get the exact sound output the original producers intended, yet music listeners have no such avenue to enjoy their music as the creators intended. In fact, one music recording can vary so dramatically from another that you are forced to guess what the reference volume should be and their mastering method could have been done on a junk set of studio monitors that aren't set for full range/high dynamic output. In contrast, everytime a movie soundtrack is mixed and mastered, it's done on the highest resolution equipment with a sound system that has a dramatic dynamic range and a kick butt subwoofer section capable of shaking the studio. You DON'T often see that kind of system in music studios, nor are there any standardized procedures for assuring the listener has a way of duplicating what they hear in the studio during mixing/mastering.

I wish the music industry would follow the movie industry and standardize their sound recording and production process so that music enthusiasts can re-create the intended experience. Right now the movie sound production and commercial products are FAR FAR FAR FAR ahead of the music industry in terms of quality, realism and fidelity as well as offering consumers end-user products to achieve a near-perfect room-tuning to experience the sound as it's creators intended. It's a shame when a basic, low-cost home theater system is technically higher-end than multi-thousand dollar 2-channel audio. 

Don't get me wrong. 2-channel systems have the capability to sound great. However, without a standardized system for production (like the movie industry has for soundtracks), you have to find a way to set your 2-channel music system by hand and customize your own experience because you cannot rely on the original production to be consistent from one CD to another. 

It's not the fault of the equipement but rather because the professional production phase across the industry has no standardization or procedures for producing it's products. So, as a high end user, you are left guessing what should 'sound' correct.

I set my system according to what I think it should sound like. That's what my ultimate goal is. Is to have the ability to produce decently loud, unclipped sound that represents what I think the music should sound like. That will take a lot of time and tweaking but I think it will be really good when I'm done.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> ...


That's all great Spense, but before we go start going back in circles...



icehole said:


> It's clear that everything you do has _some sort_ of purpose.
> 
> But did it ever occur to you that, by asking for advice, and then arguing with the people who are more experienced and knowledgeable that give you advice, and then doing the exact *opposite* ensures that you'll be taking the least efficient route to meet your goals?


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## Jimi77 (Jul 4, 2005)

icehole said:


> All ******** aside, a stock Bose sounds far better than an aftermarket Best Buy sytem *WITHOUT EQ.
> *
> 
> But that's not what you should strive for. And if you've spent $500+ and you're not there, you're doing something TERRIBLY wrong.



Huh, I wouldn't know since I wouldn't put anything BB carries in my car, but I've heard some crappy Bose systems. Peaky bass, no high, no lows, muddy midrange, etc. You could pick a ~$150 hu, $150 amp and $200 set of comps and destroy a Bose system (internet pricing).


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## tspence73 (Oct 14, 2008)

icehole said:


> That's all great Spense, but before we go start going back in circles...


I'm telling you and have told you that I will ultimately do things 'my way'. I will listen to suggestions, ideas and guidance but it is my system and I will make the decisions on how to proceed. You may not agree with or accept my logic but I can virtually guarantee you that my system will sound amazing when all my projects are done and the tuning is complete.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> Again, you show yourself to be stupid. By going down from 1,200 RMS peak to 500 peak that is a loss of 4db.



Ironically (but not surprisingly) it's you comment that demonstrates your stupidity. Two words: power compression. IOW, I sure as hell didn't pick up 4dbs switching my Brahma from 400rms to 1000rms.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> I'm telling you and have told you that I will ultimately do things 'my way'. I will listen to suggestions, ideas and guidance but it is my system and I will make the decisions on how to proceed. You may not agree with or accept my logic but I can virtually guarantee you that my system will sound amazing when all my projects are done and the tuning is complete.


But why argue with convention? Like I've told you before, this isn't religion, politics or culture.

I'm just curious.


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> Huh, I wouldn't know since I wouldn't put anything BB carries in my car, but I've heard some crappy Bose systems. Peaky bass, no high, no lows, muddy midrange, etc. You could pick a ~$150 hu, $150 amp and $200 set of comps and destroy a Bose system (internet pricing).


It's not always about the driver. It's also about putting the chosen driver in the proper application. I don't like Bose home systems. They are woefully short on impact and don't have a 'live' quality to them. There have been two luxury cars I have had the pleasure of hearing jazz recordings on a stock Bose system and I can tell you for SURE, they sound good. Even the bass was surprisingly decent, lending depth to the vocals and instruments and the overall tonality was really realistic. The acoustics of the car no doubt had a pretty dramatic effect on this but I think the drivers used in the car were well chosen to perform well in this environment.

It's not that Best Buy carries poor products, it's that the people installing and tuning them don't know what good sound is.:thumbsdown:


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> Ironically (but not surprisingly) it's you comment that demonstrates your stupidity. Two words: power compression. IOW, I sure as hell didn't pick up 4dbs switching my Brahma from 400rms to 1000rms.


There is usually little to no compression on speakers that play within their stated RMS rating. The RE SE 12's have a 600-watt RMS rating EACH. That marries perfectly to the amp's 1200-watt RMS peak output. THERE IS NO POWER COMPRESSION GOING ON HERE. Please STOP.:afro:


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## tspence73 (Oct 14, 2008)

icehole said:


> But why argue with convention? Like I've told you before, this isn't religion, politics or culture.
> 
> I'm just curious.


And you have never disagreed with convention before? We all have our own logic for why we do what we do and our own experiences and way of looking at things. It doesn't make it wrong as long as you achieve your goal in the end.


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## Knobby Digital (Aug 17, 2008)

Jimi77 said:


> Huh, I wouldn't know since I wouldn't put anything BB carries in my car, but I've heard some crappy Bose systems. Peaky bass, no high, no lows, muddy midrange, etc. You could pick a ~$150 hu, $150 amp and $200 set of comps and destroy a Bose system (internet pricing).


I don't put BB **** in my car either. And I suppose if that's worked for you I'd say that it's either luck or taste.

I'm not SuperCarAudioDude, and I'll be the first to admit that I have limited experience with alot of car audio lines. But I'm a musician who does production and engineering. I think I have a pretty decent understanding of how rooms affect sound. Point being that if you can't tailor the sound to your taste and environment, you're taking a gamble with the equipment and installation.

My hiatus in car audio is due to me parking my luxury cars on the streets of Chicago and Los Angeles for the last 8 years. In that time I've sat in alot of vehicles with systems and thought to myself "You spent $XXXX on that?!?!?!"


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> And you have never disagreed with convention before? We all have our own logic for why we do what we do and our own experiences and way of looking at things. It doesn't make it wrong as long as you achieve your goal in the end.


I heavily disagree with convention in religion, politics, and culture. 

But when I'm spending my money I want it to be effective. There's no point in arguing with the conventional science and wisdom in car audio.


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## tspence73 (Oct 14, 2008)

icehole said:


> I heavily disagree with convention in religion, politics, and culture.
> 
> But when I'm spending my money I want it to be effective. There's no point in arguing with the conventional science and wisdom in car audio.


There is plenty to debate in some of the methods that have been suggested to me. Such as treating the car with damping materials and deadener BEFORE you have bought your equipment. Do you think you can predict what vibrations you'll have to treat before the car system is installed? By doing the acoustic treatment first and making unfounded assumptions, you may well end up wasting money unnecessarily. For instance, I didn't deaden my doors until I had installed my comps. My doors ended up needing a lot more deadening work that I couldn't possibly have predicted ahead of time.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> There is plenty to debate in some of the methods that have been suggested to me. Such as treating the car with damping materials and deadener BEFORE you have bought your equipment. Do you think you can predict what vibrations you'll have to treat before the car system is installed? By doing the acoustic treatment first and making unfounded assumptions, you may well end up wasting money unnecessarily. For instance, I didn't deaden my doors until I had installed my comps. My doors ended up needing a lot more deadening work that I couldn't possibly have predicted ahead of time.


The one thing that CANNOT be debated are constant constraints and issues with car audio in general.

Sound deadening and EQ early ARE fundamental.


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## ca90ss (Jul 2, 2005)

tspence73 said:


> There is usually little to no compression on speakers that play within their stated RMS rating. The RE SE 12's have a 600-watt RMS rating EACH. That marries perfectly to the amp's 1200-watt RMS peak output. THERE IS NO POWER COMPRESSION GOING ON HERE. Please STOP.:afro:


********! Power compression starts with the first watt.


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## Rudeboy (Oct 16, 2005)

tspence73 said:


> I would be willing to try a fully active system but maybe you can tell me where I can mount this extra amp out of sight?  Then I might consider this at some future time.


This is exactly why you get the reaction you do - I asked you to explain the thinking that leads you to believe that the passive x-over you have might impart a "sonic signature" that improves the speakers' ability to reproduce music. Instead you dare me to find a suitable place to hide your amp and allow that you might consider running active in the future. I'm not going to figure out where yo can mount an amp and I couldn't care less if you run passive or active. I asked you to provide some evidence for your position, that's all.


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## MarkZ (Dec 5, 2005)

Jimi77 said:


> Ironically (but not surprisingly) it's you comment that demonstrates your stupidity. Two words: power compression. IOW, I sure as hell didn't pick up 4dbs switching my Brahma from 400rms to 1000rms.


But why are people minimizing the impact of 3dB? For subwoofer applications, that's nearly a doubling of perceived loudness. 3dB is a very big deal, IMO.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> There is usually little to no compression on speakers that play within their stated RMS rating. The RE SE 12's have a 600-watt RMS rating EACH. That marries perfectly to the amp's 1200-watt RMS peak output. THERE IS NO POWER COMPRESSION GOING ON HERE. Please STOP.:afro:


Do you have proof to support this assertion?


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## Rudeboy (Oct 16, 2005)

tspence73 said:


> There is plenty to debate in some of the methods that have been suggested to me. Such as treating the car with damping materials and deadener BEFORE you have bought your equipment. Do you think you can predict what vibrations you'll have to treat before the car system is installed? By doing the acoustic treatment first and making unfounded assumptions, you may well end up wasting money unnecessarily. For instance, I didn't deaden my doors until I had installed my comps. My doors ended up needing a lot more deadening work that I couldn't possibly have predicted ahead of time.


Seriously, you've already said that your car has a noise floor in the low 90s on the highway. Treating that first has been presented as ideal, but Ihaven't said that you were wrong to approach it the way you have. You're the one who wants to insist that what you are doing is the superior course of action.


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## tspence73 (Oct 14, 2008)

ca90ss said:


> ********! Power compression starts with the first watt.


Well certain speaker engineers might argue with you. Link to proof? That would be nice. Preferably multiple links. Remember, power compression happens due to the voice coil heating up. It takes a certain amount of heat to cause compression. Like copper needs to be 200-degrees celcius (that's 392 degrees fahrenheit) to double it's resistance. That is just a 3db drop. It will take quite a bit of long term and consistent output to heat the VC up that high. I doubt at the levels I've set that and with the cooling desgin of the coil on the woofer, that it will ever see that much heat. So, anything less than a 1db loss would be virtually inaudible on these subs. That's the science. 

Your statement is misleading in that you say "it starts with the first watt". Yeah, you need to "start somewhere" to build up that heat but 1 watt continuous will not heat up the coil enough to cause compression and a 34.6 volt setting on my amp isn't going to likely cause compression either considering most of the sound will be well below the 1,200-watts RMS output (more likely even under 250-watts the vast majority of the time). Running a speaker at it's rated RMS intermittently is not likely to cause power compression.


----------



## Knobby Digital (Aug 17, 2008)

Rudeboy said:


> I asked you to provide some evidence for your position, that's all.





MarkZ said:


> Do you have proof to support this assertion?




I suppose this is where the "How do you know it doesn't..." approach -straight out of the Bush admin playbook- comes in.



edit: there it went.


----------



## ca90ss (Jul 2, 2005)

tspence73 said:


> Well certain speaker engineers might argue with you. Link to proof? That would be nice. Preferably multiple links.


Why don't you show me proof to the contrary? Preferably with multiple links.


----------



## t3sn4f2 (Jan 3, 2007)

If by power compression we mean less power delivered to the speaker because of increased voice coil temperature and thus higher impedance then.....



Abmolech said:


> Depending on the voice coil size and magnet assembly it would take around ½ minute to reach 200 degrees.
> Consider our example of a 4 ohm driver, having a DC resistance (DCR) of 3 ohms at 20 degrees Celsius
> 
> The ratio of nominal impedance (Z) to DCR is 4 / 3 = 1.33:1
> ...


http://www.diymobileaudio.com/forum/diy-mobile-audio/25864-power-requirements-typical-setup-2.html


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> Again, you show yourself to be stupid. By going down from 1,200 RMS peak to 500 peak that is a loss of 4db. That is an audible loss of output when the 1,200-watt RMS peak is BARELY making what I consider a MINIMUM output for a sound quality system. I'm not going to go back to clipping my sub stage again. Sorry. When I want to go to 4-ohms, I will upgrade the amp.


You are ****ing retarded.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> Have you ever heard a factory Bose system in a luxury car? It's actually pretty good. Even if Bose home audio blows, their factory auto system sounds good. There are stock systems in luxury cars that sound quite good. I don't know what luxury cars you've been listening to.


Yes I have heard many as well as Boston acoustics and many others, they all didn't live up to my standards, there was no balance in the system it was all emphasized on the treble and upper bass ranges and was not very pleasing. Bose can't really do anything well ever, as I've discovered from sampling every single product they make (there aren't that many).


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> There are people who run 10's and get good output because they run large enclosures or dual 10's. I found a sealed 10" wasn't enough. I actually went on a recommendation from a "so called" expert on another forum, so you can understand now why I'm skeptical and think anyone can be false. Just like you. First you criticize me for clipping the amp to get proper output, then when I explain WHY you jump out and say "no ****"? You're an idiot. Just shut up already you moron. I'm tired of your drivel.


Clipping an amp never means 'proper output' you idiot, and of course two 12's have 'more output' than one 10, your problem had nothing to do with clipping ever and everything to do with you preference for more bass. Stop blaming your equipment when you don't have the right things in place.


----------



## tspence73 (Oct 14, 2008)

ca90ss said:


> Why don't you show me proof to the contrary? Preferably with multiple links.


I don't need to link up proof buddy. Think real world here. 200-degrees celcius would melt solder on the speaker terminals. I don't see a whole lot of soldered terminals on subs coming undone on their own. Coils don't reach those temps very often and the temps would transfer onto the speaker cables as well. 396-degrees fahrenheit would be quite a bit too dangerous to allow your speaker cables to get to. See, you guys are arguing in straight, unchanging voltage that doesn't exist in much of any music playback. Most music playback material (even highly compressed material) averages no more the -8db average. So, if I set my amp to 1,200 watts RMS, then put an average of -8db music (which is still more than you'll likely ever see), then the average output in watts would be 451-watts. A more realistic -10db would mean 360-watts average. Remember, that's spread across FOUR 300-watt RMS voice coils which have a vent airflow power on the magnet assembly to cool the coils. You aren't likely going to see 200-degrees celcius with those numbers. I could be wrong but I doubt it.


----------



## ca90ss (Jul 2, 2005)

tspence73 said:


> I don't need to link up proof buddy. Think real world here. 200-degrees celcius would melt solder on the speaker terminals. I don't see a whole lot of soldered terminals on subs coming undone on their own. Coils don't reach those temps very often and the temps would transfer onto the speaker cables as well. 396-degrees fahrenheit would be quite a bit too dangerous to allow your speaker cables to get to.


I suggest you stop now before further embarrassing yourself.


----------



## MarkZ (Dec 5, 2005)

Now I see what you guys mean.


----------



## shadowfactory (Oct 20, 2008)

Andy Wehmeyer said:


> 1. Speakers don't require an enclosure. Baffle? Yes. Enclosure? No, especially when a high pass filter is used.
> 
> 2. Car companies' desires for high-end branded audio systems refutes your suggestion that consumers don't care about the quality of the audio systems in their cars. Furthermore, plenty of studies about listening preferences suggest just the opposite of your statement.


Note that I didn't mention JBL aftermarket systems in my analysis. :tongue3:
They are the only setups I've actually been pleased with in cars. My rant was more about Bose than anything else.


----------



## tspence73 (Oct 14, 2008)

shadowfactory said:


> Clipping an amp never means 'proper output' you idiot, and of course two 12's have 'more output' than one 10, your problem had nothing to do with clipping ever and everything to do with you preference for more bass. Stop blaming your equipment when you don't have the right things in place.


Didn't I tell you to shut up already? :tongue2:


----------



## tspence73 (Oct 14, 2008)

ca90ss said:


> I suggest you stop now before further embarrassing yourself.





> http://www.irational.org/sic/radio/solder.html


_*Solder melts at around 190 degrees Centigrade*, and the bit reaches a temperature of over 250 degrees Centigrade._

It takes 200-degrees for copper to double resistance which would be 3db power compression. It takes 190-degrees to melt solder. At what point am I to be embarassed now?


----------



## tspence73 (Oct 14, 2008)

MarkZ said:


> Do you have proof to support this assertion?


Proof:

Power compression question - CARSOUND.COM Forum

_Power compression comes from heating the voice coil. As you heat metals, the resistance of the metal increases. Heat copper by 200 deg C, and you double the resistance of the copper. That means you just doubled the DCR of your woofer, which will cause a 3 dB loss in output.

Dan Wiggins
Adire Audio_

---------------------------------------

_Hi tspence,

I'm sorry for the delay. I was waiting on a reply from one of
our engineers. According to our engineers, we do not test for power
compression in our full range component systems or the coaxial type
speakers. *Testing has found the effects to be negligible when listening
to music at the speaker's rated power or lower.* The result of serious
power compression caused by excessive heat would cause the speakers to
fail.


Sincerely, 
James Pagano 
Internet Support Specialist 
Harman Consumer Group
Woodbury, NY _

How much more proof do you want? I'm sure I can find more if you want it. I'm sure you "know what you guys mean" now, huh? You shouldn't just trust what others tell you without links and proof like I'm posting here. If you disagree with me, then you disagree with the sources of the info I'm posting.


----------



## ca90ss (Jul 2, 2005)

tspence73 said:


> _Solder melts at around 190 degrees Centigrade, and the bit reaches a temperature of over 250 degrees Centigrade._
> 
> It takes 200-degrees for copper to double resistance which would be 3db power compression. It takes 190-degrees to melt solder. At what point am I to be embarassed now?


We're talking about vc temp not speaker terminal temp. Why don't you take in to account tire temperature while you're at it.:rolleyes2:


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## t3sn4f2 (Jan 3, 2007)

It's magic!. I've also seen it happen on my pots and pans. Those babies get scorching hot but the rubber handle on them never melts. Spooky physics!


----------



## MarkZ (Dec 5, 2005)

tspence73 said:


> Proof:
> 
> Power compression question - CARSOUND.COM Forum
> 
> ...


An "internet support specialist's" word isn't exactly proof. Especially when Dan Wiggins contradicts him in the first thing you wrote. Maybe you can show me the outcome of the so-called test and a description of how it was performed? Or...well, we could just trust the word of the marketing department of a manufacturer.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> I'm telling you and have told you that I will ultimately do things 'my way'. I will listen to suggestions, ideas and guidance but it is my system and I will make the decisions on how to proceed. You may not agree with or accept my logic but I can virtually guarantee you that my system will sound amazing when all my projects are done and the tuning is complete.


If your mind is already made up stop posting for advice.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> Didn't I tell you to shut up already? :tongue2:


:cwm27:


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> _*Solder melts at around 190 degrees Centigrade*, and the bit reaches a temperature of over 250 degrees Centigrade._


There are like 20 different solder alloys all with different melting points.....


----------



## tspence73 (Oct 14, 2008)

shadowfactory said:


> If your mind is already made up stop posting for advice.


When I know everything then I'll stop asking for advice. I'm not the most knowledgable person but I try to apply what I know the best I can. I take advice, think about it and apply it as I think I should. Only here does it seem to be wrong to ask I suppose. So sue me for not taking every piece of advice offered. I'm thankful for what people want to share and some of this info has been good to add to what I'm trying to accomplish. Some of it is optional.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> When I know everything then I'll stop asking for advice.


When you become the omnipotent GOD?


----------



## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> When I know everything then I'll stop asking for advice. I'm not the most knowledgable person but I try to apply what I know the best I can. I take advice, think about it and apply it as I think I should. Only here does it seem to be wrong to ask I suppose. So sue me for not taking every piece of advice offered. I'm thankful for what people want to share and some of this info has been good to add to what I'm trying to accomplish. Some of it is optional.


The coil can withstand that temp, the wire that connects to the terminal can too, BUT the single strand that connects the coil to the terminal does not get that hot since the heat is generated where the magnetic field is produced which is not part of the single stand going to the coil.


----------



## tspence73 (Oct 14, 2008)

t3sn4f2 said:


> The coil can withstand that temp, the wire that connects to the terminal can too, BUT the single strand that connects the coil to the terminal does not get that hot since the heat is generated where the magnetic field is produced which is not part of the single stand going to the coil.


What about heat transference? In time any metal connected to that heat source will conduct that heat, eventually all the way up the speaker wire and to the amp, kicking it into protect. The solder would have long melted before 200-degrees celcius reached up the wire to the amp.


----------



## Rudeboy (Oct 16, 2005)

MarkZ said:


> Now I see what you guys mean.


Has to be experience to be believed.


----------



## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> What about heat transference? In time any metal connected to that heat source will conduct that heat, eventually all the way up the speaker wire and to the amp, kicking it into protect.


The heat will escape to its surrounding or the wire will burn up well before it can transfer to the terminal. Pots and Pans!


----------



## Jimi77 (Jul 4, 2005)

tspence73 said:


> There is usually little to no compression on speakers that play within their stated RMS rating. The RE SE 12's have a 600-watt RMS rating EACH. That marries perfectly to the amp's 1200-watt RMS peak output. THERE IS NO POWER COMPRESSION GOING ON HERE. Please STOP.:afro:



:lol: Only speakers playing outside their RMS ratings have power compression. Okay if you say so. :lol: 

Seriously, if you don't what you're talking about (which is almost always), then don't say anything. 

Audio and Loudspeaker Design Guide Lines

http://www.soundonsound.com/sos/Jul02/articles/monitors2.asp

Feel the magnet or the cone the next time you've been blasting the system and tell me the VCs aren't reaching well over 120 degrees.


----------



## Rudeboy (Oct 16, 2005)

t3sn4f2 said:


> The heat will escape to its surrounding or the wire will burn up well before it can transfer to the terminal. Pots and Pans!


Wait, you mean I don't need all of my speaker wire fans?


----------



## tspence73 (Oct 14, 2008)

t3sn4f2 said:


> The heat will escape to its surrounding or the wire will burn up well before it can transfer to the terminal. Pots and Pans!


In other words, if your coil stays too long at a temperature of 200 degrees celcius, bye bye voice coil. 200-degrees = 3db of power compression. Most speakers will not be a 200-degrees at any time and if it is, it's reaching the thermal limits of the voice coil or it's surrounding components. Hence, it's unlikely my subs are reaching anywhere near 200-degrees celcius with an average of 300-400 watts spread amongst 4 voice coils. Therefore the power compression, if any, is likely less than 1db of loss, hence INAUDIBLE. That was my point. Power compression in my subwoofers at my current settings are not going to be an issue. The argument on that point should be closed now.


----------



## Jimi77 (Jul 4, 2005)

MarkZ said:


> But why are people minimizing the impact of 3dB? For subwoofer applications, that's nearly a doubling of perceived loudness. 3dB is a very big deal, IMO.



I'm not minimizing the impact. I'm pointing out that Tspence is calling other people stupid, then goes on to make an inaccurate statement and has now followed it up with another inaccurate statement. Technically even 1 db has some impact. FYI, I believe it's 10db = "twice" as loud.


----------



## t3sn4f2 (Jan 3, 2007)

Rudeboy said:


> Wait, you mean I don't need all of my speaker wire fans?


It _can_ help push the electrons along if you aim them the right way though. :wacky:


----------



## shadowfactory (Oct 20, 2008)

t3sn4f2 said:


> It _can_ help push the electrons along if you aim them the right way though. :wacky:


All my speaker wires are directional so the electrons flow better away from the amp. :laugh:


----------



## Jimi77 (Jul 4, 2005)

Rudeboy said:


> This is exactly why you get the reaction you do - I asked you to explain the thinking that leads you to believe that the passive x-over you have might impart a "sonic signature" that improves the speakers' ability to reproduce music. Instead you dare me to find a suitable place to hide your amp and allow that you might consider running active in the future. I'm not going to figure out where yo can mount an amp and I couldn't care less if you run passive or active. I asked you to provide some evidence for your position, that's all.


Ironically, tspence rejects any advice given that isn't "proven" with some sort of scientific dissertation, yet doesn't hold himself to the same standard.


----------



## t3sn4f2 (Jan 3, 2007)

Jimi77 said:


> I'm not minimizing the impact. I'm pointing out that Tspence is calling other people stupid, then goes on to make an inaccurate statement and has now followed it up with another inaccurate statement. Technically even 1 db has some impact. FYI, I believe it's 10db = "twice" as loud.


No such thing as "twice as loud". It'd be like saying something hurts twice as much.


----------



## Jimi77 (Jul 4, 2005)

t3sn4f2 said:


> No such thing as "twice as loud".


Agreed. That's why I used the quotes too. :cool2:


----------



## tspence73 (Oct 14, 2008)

Jimi77 said:


> Ironically, tspence rejects any advice given that isn't "proven" with some sort of scientific dissertation, yet doesn't hold himself to the same standard.


I am obviously trying to apply what I know to this debate. I'm not an engineer but know enough that when someone explains something that doesn't quite add up, I'm going to question it and ask for evidence. So far, there is no proof offered that at my current setting on my amp that power compression is making any REAL impact on the bass response. If it is, it's likely minimal at best (certainly no more than 1db, which is barely on the threshold of audibility) and so the argument is still whether my subwoofers are experiencing audible power compression effects and so far no one has offered anything that has convinced me that I have a significant issue. Four large voice coils getting AT MOST an average of 100-watts each when I have the volume turned all the way up to the edge of clipping. They are not likely to get hot enough to run into major compression issues. Hell, I have more to worry about with my midbasses and comps than my subs.


----------



## t3sn4f2 (Jan 3, 2007)

Jimi77 said:


> Agreed. That's why I used the quotes too. :cool2:


Opps, missed that. :bash:


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> When I know everything then I'll stop asking for advice.


This perfectly captures the entire problem you have with your approach to learning. You don't enter a new field of study and say, "Gee, I don't know much now, but once I study for about 2 weeks I'll know everything there is to know and I'll be done."
Things do not work that way. 

Andy said something very interesting (which you ignored) that even he, who has more experience that most of the other posters put together, still continues to learn and approaches the topic with humility. There is never an 'end' to knowledge, there is always something new to pick up. 

And the smartest people are the ones who recognize and embrace that fact, that you must always approach a subject with reverence and humility as it is truly _*IMPOSSIBLE*_ to 'know everything' about any discipline.


----------



## shadowfactory (Oct 20, 2008)

Jimi77 said:


> Ironically, tspence rejects any advice given that isn't "proven" with some sort of scientific dissertation, yet doesn't hold himself to the same standard.


THIS IS THE MOST PERFECT DESCRIPTION OF TSPENCE I HAVE EVER READ.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> I'm not an engineer but know enough that when someone explains something that doesn't quite add up, I'm going to question it and ask for evidence.


That's exactly what people are doing to you as well, so stop getting your panties in a bunch about it. You aren't a victim who is being attacked, you are only getting a dose of your own medicine.


----------



## tspence73 (Oct 14, 2008)

shadowfactory said:


> THIS IS THE MOST PERFECT DESCRIPTION OF TSPENCE I HAVE EVER READ.


I've provided my links and my proof to the thread as to my line of thinking. Are you just glossing over what evidence I've offered?


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> I've provided my links and my proof to the thread as to my line of thinking. Are you just glossing over what evidence I've offered?



You mean the one contradictory email you got from some random guy at Harmon? WOW THAT SOLVES EVERYTHING. :smart:

Now that you posted one link, go back and read the PAGES AND PAGES AND PAGES of other links given to you. You said you want to learn, start doing it.

And with regards to your 1 ohm subs, how do you know it will sound worse if you have NEVER HEARD IT THAT WAY? Can you travel into the future and hear the 'loss of SPL'? You can slap your dick on your calculator all you want, doesn't change the fact that you have no idea what it will actually sound like until you do it.


----------



## t3sn4f2 (Jan 3, 2007)

One thing you gotta admire about the spencester, he doesn't get butt hurt about being bashed. :thumbsup:


----------



## shadowfactory (Oct 20, 2008)

t3sn4f2 said:


> One thing you gotta admire about the spencester, he doesn't get butt hurt about being bashed. :thumbsup:


In his mind all attention is positive. It's called distorted reality disorder.


----------



## t3sn4f2 (Jan 3, 2007)

shadowfactory said:


> In his mind all attention is positive. It's called distorted reality disorder.


Paradoxes are intolerable to some.


----------



## Knobby Digital (Aug 17, 2008)

t3sn4f2 said:


> One thing you gotta admire about the spencester, he doesn't get butt hurt about being bashed. :thumbsup:


Untrue. He'll pulls (ignorant) arrogant dick moves on the regular.

He only continues because nothing gets through his skull, and he wants people to spoon feed him info.

























....Only to tell them they're wrong.


----------



## Rudeboy (Oct 16, 2005)

tspence73 said:


> I've provided my links and my proof to the thread as to my line of thinking. Are you just glossing over what evidence I've offered?


Please explain what your passive x-overs are contributing to the "sonic signature" that can't be duplicated with active x-overs.:ears:


----------



## Rudeboy (Oct 16, 2005)

t3sn4f2 said:


> No such thing as "twice as loud". It'd be like saying something hurts twice as much.


I disagree - this thread hurts twice as much as most.


----------



## Jimi77 (Jul 4, 2005)

tspence73 said:


> _*Solder melts at around 190 degrees Centigrade*, and the bit reaches a temperature of over 250 degrees Centigrade._
> 
> It takes 200-degrees for copper to double resistance which would be 3db power compression. It takes 190-degrees to melt solder. At what point am I to be embarassed now?



I'd say you should have been embarassed the second you hit "submit reply." If not then, then you should be embarassed everytime you VC hits 200C.



P.G.L Mills & OJ Hawksford (aka some really smart dudes) said:


> :smart: The voice coil resistance is of specific concern, as it is usually the dominant element. As a result of self-heating in excess of 200 degrees C, a significant increase in coil resistance occures of typically .4%/degree D for copper, leading to sensitivity loss, lack of damping and crossover misalignment. :smart:


http://www.essex.ac.uk/dces/researc...J12 Distortion reduction MC current drive.pdf

I guess that explains why my speakers keep desoldering themselves..... I thought it was gremlins. Tspence, since you're a soldering expert, maybe you explain to us why I can't effectively do "large" soldering jobs with the pencil tip on my soldering iron. When you're done with explaination, stop and think for a few moments, then you'll have you answer to why 200 degress C doesn't transfer down a strand of copper thru a "thick" tinsel lead to the solder joint.


----------



## t3sn4f2 (Jan 3, 2007)

icehole said:


> Untrue. He'll pulls (ignorant) arrogant dick moves on the regular.
> 
> He only continues because nothing gets through his skull, and he wants people to spoon feed him info.
> 
> ...



I stand corrected then. I haven't been following the drama but to me he's only gone against reasonable proof.


----------



## tspence73 (Oct 14, 2008)

shadowfactory said:


> You mean the one contradictory email you got from some random guy at Harmon? WOW THAT SOLVES EVERYTHING. :smart:


Actually, that email states that when played within it's RMS that power compression effects aren't an audible concern or did you miss the bolded part of the email? It didn't contradict anything.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> Actually, that email states that when played within it's RMS that power compression effects aren't an audible concern or did you miss the bolded part of the email? It didn't contradict anything.


Cool that's really awesome and interesting now shut up and go read some articles that have science in them. :dunce:

http://www.diymobileaudio.com/forum/diy-mobile-audio/50592-diyma-collection-good-reads.html

Then go hook up your subs at 4 ohms so the sun can explode.


----------



## tspence73 (Oct 14, 2008)

Jimi77 said:


> I'd say you should have been embarassed the second you hit "submit reply." If not then, then you should be embarassed everytime you VC hits 200C.
> 
> 
> 
> ...


If you let the soldering iron sit on your speaker cable long enough, the heat will move up the wire. It takes time, but it will. Just be patient. :beatnik:


----------



## tspence73 (Oct 14, 2008)

shadowfactory said:


> Cool that's really awesome and interesting now shut up and go read some articles that have science in them. :dunce:
> 
> http://www.diymobileaudio.com/forum/diy-mobile-audio/50592-diyma-collection-good-reads.html
> 
> Then go hook up your subs at 4 ohms so the sun can explode.


A link to a bunch of unrelated other links is not getting to the point. Please present your point. Show me how 300-400 watts average spread out to 4 voice coils that can each handle 300-watts RMS is cooking them up to the level of thermal power compression. I will await your skilled engineering response on this.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> If you let the soldering iron sit on your speaker cable long enough, the heat will move up the wire. It takes time, but it will. Just be patient. :beatnik:


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> A link to a bunch of unrelated other links is not getting to the point. Please present your point. Show me how 300-400 watts average spread out to 4 voice coils that can each handle 300-watts RMS is cooking them up to the level of thermal power compression. I will await your skilled engineering response on this.


Actually it is you dolt, as whatever retarded point you are stuck on at the moment pales in comparison to the mountain of ignorance cascading forth from your keyboard which would be greatly reduced by the aforementioned link. Now, shut the **** up and read. 

Then please tell me how you know they are getting '300-400 watts average' with music. Are you a human watt meter?

Why the **** are you even talking about all this stupid theoretical watt figures and thermal ****? Do you think your subs will magically melt if you don't slap your dick on your calculator enough? GO EXPERIMENT AND DO THINGS TO LEARN.

Jesus Chirst, you aren't a CERN scientist conducting atomic experiments, you are a retard hooking up subs in your car... its not ****ing rocket science.


----------



## tspence73 (Oct 14, 2008)

t3sn4f2 said:


> I stand corrected then. I haven't been following the drama but to me he's only gone against reasonable proof.


Again. Please provide "reasonable proof" that 300-400 watts average is getting my 4 voice coils up to thermal power compression effects and what db level these effects are at, if any exist. If you know this answer, just show it. From what I've seen presented and linked so far, there isn't any reasonable proof showing my subs are experiencing audible power compression effects. Please show the proof or explain using math what level of power compression my subs are getting. It would be cool to know this either way.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> Again. Please provide "reasonable proof" that 300-400 watts average is getting my 4 voice coils


Please provide reasonable proof that this is actually happening.


----------



## tspence73 (Oct 14, 2008)

shadowfactory said:


> Actually it is you dolt, as whatever retarded point you are stuck on at the moment pales in comparison to the mountain of ignorance cascading forth from your keyboard which would be greatly reduced by the aforementioned link. Now, shut the **** up and read.
> 
> Then please tell me how you know they are getting '300-400 watts average' with music. Are you a human watt meter?


If YOU actually READ my earlier post, I explained how I am averaging 300-400 watts at PEAK unclipped volume output on my headunit using -8db to -10db average music levels in modern recordings. It's pretty easy math, even for you. Here:

3db is double the power and -3db is half the power.

-10db is 3.33 times less powerful than 0db. 1200-watts is produced at 0db from 20-100Hz. When music is playing at -10db average, you get this: 1200/3.33 = 360 watts average in music according to the pre-amp volume setting of 75% of max (as it was set with my 0db test tone and DMM).

I likely won't be pushing my volume up to that limit very often but even if I did, the effects of power compression would be small. Most of the time during music playback, it won't be an issue at all.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> If YOU actually READ my earlier post


I did, it was wrong then and posting it twice doesn't change that. 




tspence73 said:


> from 20-100Hz. When music is playing at -10db average,


Which it isn't, which ruins your whole 'calculation.'


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> 1200-watts is produced at 0db from 20-100Hz.


In magical theoretical land maybe, but not in reality.

Again, you ignore my point that all your calculator dick slapping is based on loose approximates and frankly made up numbers that don't translate directly to reality. If you want to talk theory, go read a book, otherwise go do ****.

And for the love of god, hook your subs up at 4 ohms.


----------



## MarkZ (Dec 5, 2005)

Jimi77 said:


> I'm not minimizing the impact. I'm pointing out that Tspence is calling other people stupid, then goes on to make an inaccurate statement and has now followed it up with another inaccurate statement. Technically even 1 db has some impact. FYI, I believe it's 10db = "twice" as loud.


At 1kHz, maybe. The Fletcher-Munson curves begin to approach around 4-5dB differences, I believe, when we get down below 100Hz or so. Add to that the tactile cue, which I don't think has been studied well in combination with the auditory one. In any case, a difference of 3dB in that part of the spectrum is quite significant. 1dB is perceptible too under the right circumstances -- but the difference between 1dB and 3dB is quite large too (2dB, in fact  ).



t3sn4f2 said:


> No such thing as "twice as loud". It'd be like saying something hurts twice as much.


Heh, there's such a thing as that too. These are well established psychophysical metrics that have been around longer than you or I have. Sometimes it's hard to identify exactly what it means for something to be twice the perceptible magnitude as something else, but there are a number of ways of defining it. Ultimately, it boils down to the very essence of numerosity. If you're interested in that stuff, I strongly suggest reading SS Stevens' book on the subject, which is considered one of the psychophysics "bibles" from one of the pioneers in the field.


----------



## Knobby Digital (Aug 17, 2008)

t3sn4f2 said:


> I stand corrected then. I haven't been following the drama but to me he's only gone against reasonable proof.



Here's a couple of instances in this thread alone.



tspence73 said:


> yo mama is a poor midbass driver.





tspence73 said:


> Are the squeaky gears a turnin'? Ah, that's right





tspence73 said:


> My system is not only going to meet my goals but likely exceed them and very likely be tweaked and tuned better than yours by the time I'm done.





tspence73 said:


> Don't just run your mouth. Link up something that shows what you're talking about. Do you know how many silly myths exist on the web when it comes to audio?





tspence73 said:


> WRONG. BUZZ. You are an idiot.





tspence73 said:


> I'll bet you haven't heard the comps. Most likely the coax.





tspence73 said:


> Didn't I tell you to shut up already? :tongue2:


----------



## Jimi77 (Jul 4, 2005)

tspence73 said:


> I am obviously trying to apply what I know to this debate. I'm not an engineer but know enough that when someone explains something that doesn't quite add up, I'm going to question it and ask for evidence. So far, there is no proof offered that at my current setting on my amp that power compression is making any REAL impact on the bass response. If it is, it's likely minimal at best (certainly no more than 1db, which is barely on the threshold of audibility) and so the argument is still whether my subwoofers are experiencing audible power compression effects and so far no one has offered anything that has convinced me that I have a significant issue. Four large voice coils getting AT MOST an average of 100-watts each when I have the volume turned all the way up to the edge of clipping. They are not likely to get hot enough to run into major compression issues. Hell, I have more to worry about with my midbasses and comps than my subs.


No, you're just being argumentative. Furthermore, you didn't ask for more proof, you stated that I was wrong with no evidence to the contrary like I'm sort of ******* just posting random crap on the internet to hear the neat clicky, clicky sound my keyboard makes. 



tspence73 said:


> There is usually little to no compression on speakers that play within their stated RMS rating. The RE SE 12's have a 600-watt RMS rating EACH. That marries perfectly to the amp's 1200-watt RMS peak output. THERE IS NO POWER COMPRESSION GOING ON HERE. Please STOP.:afro:


FYI, power compression is "common knowledge" on most audio forums. Whoever told you try a 4 ohm load didn't just pull that their arse, and they offered you real world experience. Same thing when I told you to move your sub box. But rather than take 5 minutes out of your day to see what happens you spent an hour arguing on here. Brilliant.

Rather than worry about your midbass problems, I'd fix that massive hole in your FR as result of your poorly designed sub stage. Loose the 6x9s. Then you'll know what you need from the midbass driver. I'd suggest a much simplier approach, like loosing the JLs and Refs and going 2-way with a high-end comp like the Focal KPs, Hertz, Alpine Type X pros, etc. Or given the amount of power you have available, do an active 2-way with "raw" drivers. KISS (keep it simple stupid): you have enough problems with the most basic concepts in car audio, designing a 4-way system with 6 phase relationships and 6 intensity relationships to iron out is way beyond your skill set.


----------



## MarkZ (Dec 5, 2005)

tspence73 said:


> I am obviously trying to apply what I know to this debate. I'm not an engineer but know enough that when someone explains something that doesn't quite add up, I'm going to question it and ask for evidence. So far, there is no proof offered that at my current setting on my amp that power compression is making any REAL impact on the bass response. If it is, it's likely minimal at best (certainly no more than 1db, which is barely on the threshold of audibility)


You're guessing. In fact, you've pulled these numbers right out of the air.

You've offered no proof of your assertions. Why should we simply take your word for it? [Sound familiar?]


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## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> If YOU actually READ my earlier post, I explained how I am averaging 300-400 watts at PEAK unclipped volume output on my headunit using -8db to -10db average music levels in modern recordings. It's pretty easy math, even for you. Here:
> 
> 3db is double the power and -3db is half the power.
> *
> ...


It's actually 10 times less but anyways, it's the peaks that will cause the increase in temp. You aren't talking about second in between them.


----------



## MarkZ (Dec 5, 2005)

tspence73 said:


> If you let the soldering iron sit on your speaker cable long enough, the heat will move up the wire. It takes time, but it will. Just be patient. :beatnik:


True or false: the temperature at the distal end of a 1 foot length of copper wire will be the same as the temperature at the site where the soldering iron tip meets the wire.


----------



## t3sn4f2 (Jan 3, 2007)

MarkZ said:


> Heh, there's such a thing as that too. These are well established psychophysical metrics that have been around longer than you or I have. Sometimes it's hard to identify exactly what it means for something to be twice the perceptible magnitude as something else, but there are a number of ways of defining it. Ultimately, it boils down to the very essence of numerosity. If you're interested in that stuff, I strongly suggest reading SS Stevens' book on the subject, which is considered one of the psychophysics "bibles" from one of the pioneers in the field.


Interesting, but how concrete is it really if the individual perception will dominate the average. How reliable would it be if I told you that the water in a pool was not too cold, if you did not know I had a high tolerance for cold water.


----------



## shadowfactory (Oct 20, 2008)

MarkZ said:


> True or false: the temperature at the distal end of a 1 foot length of copper wire will be the same as the temperature at the site where the soldering iron tip meets the wire.


Copper wire can't radiate heat, it stores it all like a thermos! :laugh2:	:laugh2:	:laugh2:	:laugh2:


----------



## MarkZ (Dec 5, 2005)

tspence73 said:


> A link to a bunch of unrelated other links is not getting to the point. Please present your point. Show me how 300-400 watts average spread out to 4 voice coils that can each handle 300-watts RMS is cooking them up to the level of thermal power compression. I will await your skilled engineering response on this.


For starters, since the "dual voice coils" share the same space, you can't consider them separate coils when analyzing their ability to dissipate heat. Your sub can supposedly dissipate 600w; if you drove only one of the coils, that doesn't mean it could only dissipate 300w. It would actually dissipate more than that, so let's not throw red herring into the questions anymore.

Second point. To my knowledge, power compression is a linear effect (for a constant current source). That is, there isn't a point where suddenly power compression kicks in. In other words, it's not like you'll have all kinds of power compression at 700w but none at all at 600w. So your logic is faulty from the very start -- you're artificially segregating the effect into two regions when in fact it's a continuum. The equation that governs VC resistance is:

Rt = R0 * [1 + a*(Tt - T0)]

where a is the temperature coefficient, R0 is initial resistance, Tt is final temperature, and T0 is room temperature (at which R0 is measured). In the peer-reviewed paper that I took that equation from, the next sentence reads: "it is not uncommon for voice coil temperatures to reach the range of 200 degrees C". (Mark Gander, j.AES, 1986).

Third, you've yet to demonstrate that your speakers somehow defy a well-accepted effect that permeates the audio literature. And you've used hyperbole in the process. The question isn't whether or not your speakers are affected by power compression -- that's absurd. The question is HOW MUCH power compression affects your speakers. I have several peer-reviewed papers (j.AES, I think) on the effect that I can make available to you if you're really interested in learning, like you say you are. I have three in pdf format on my server right now.

Care to offer proof of your assertions? Or should we just drop it?


----------



## Jimi77 (Jul 4, 2005)

tspence73 said:


> If you let the soldering iron sit on your speaker cable long enough, the heat will move up the wire. It takes time, but it will. Just be patient. :beatnik:


Spoken like somebody with little to no soldering experience. So why isn't the solder melting on my speakers???? Oh wait I notice you still aren't acknowledging VCs exceed 200c - oh well so much for scientific proof. :bash: 

http://www.almainternational.org/content/TM-324 rev DRAFT.pdf :bash: 

http://www.jstage.jst.go.jp/article/ast/21/2/57/_pdf :bash: 

Oh no, say it isn't a so. A manufacture that actually lists power compression as a spec. And it's a whole ~3db at full RMS. OMG, imagine that. :bash: :bash: :bash: :bash: 

http://www.jblpro.ru/pdf/2020H.PDF


----------



## MarkZ (Dec 5, 2005)

t3sn4f2 said:


> Interesting, but how concrete is it really if the individual perception will dominate the average. How reliable would it be if I told you that the water in a pool was not too cold, if you did not know I had a high tolerance for cold water.


Individual variation exists. People will yield different curves, if you will. But that just means the measurement will be different, not the metric. The Sone was developed as a unit of measure precisely to quantify the relationship between the intensity of two sounds and the perception of their intensity. That's what we're looking at on the Fletcher-Munson curves. To arrive at those curves, there's a lot of averaging going on to reduce individual variability. But, conceptually, the idea of something being twice as intense as something else is a real one, and tends to provide insight into the sensory apparatus. For example, the intensity of smell curve will differ in shape from the intensity of sounds, etc. You can see that when you plot actual intensity versus perceived intensity -- it's not usually a straight line.


----------



## shadowfactory (Oct 20, 2008)

Now I'm just waiting for Tspence to not read all of this (let alone begin to understand it) and come up with a new retarded 'problem' or 'calculation' to cluster ****.


----------



## tspence73 (Oct 14, 2008)

Jimi77 said:


> Spoken like somebody with little to no soldering experience. So why isn't the solder melting on my speakers???? Oh wait I notice you still aren't acknowledging VCs exceed 200c - oh well so much for scientific proof. :bash:
> 
> http://www.almainternational.org/content/TM-324 rev DRAFT.pdf :bash:
> 
> ...


There is a good chance other manufacturers don't rate power compression because their RMS power rating could be below the point of any audible perception.


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## tspence73 (Oct 14, 2008)

Is everyone enjoying this thread? Got your popcorn out? It could get better. Stay tuned. :snacks:


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> Is everyone enjoying this thread? Got your popcorn out? It could get better. Stay tuned. :snacks:


Are you going to commit suicide on your webcam??!?!?! :thumbsup::thumbsup::thumbsup::thumbsup::thumbsup:


"In his mind all attention is positive. It's called distorted reality disorder."
See? It's true.


----------



## t3sn4f2 (Jan 3, 2007)

MarkZ said:


> Individual variation exists. People will yield different curves, if you will. But that just means the measurement will be different, not the metric. The Sone was developed as a unit of measure precisely to quantify the relationship between the intensity of two sounds and the perception of their intensity. That's what we're looking at on the Fletcher-Munson curves. To arrive at those curves, there's a lot of averaging going on to reduce individual variability. *But, conceptually, the idea of something being twice as intense as something else is a real one, and tends to provide insight into the sensory apparatus.* For example, the intensity of smell curve will differ in shape from the intensity of sounds, etc. You can see that when you plot actual intensity versus perceived intensity -- it's not usually a straight line.


I see what you mean now, I guess by my original statement I meant that it serves no useful tactile purpose and not that it does not exist.


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## tspence73 (Oct 14, 2008)

t3sn4f2 said:


> It's actually 10 times less but anyways, it's the peaks that will cause the increase in temp. You aren't talking about second in between them.


3db is double the power, is it not? Then wouldn't it follow that 10db is 3.33 times the power? Color me confused here.


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## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> Is everyone enjoying this thread? Got your popcorn out? It could get better. Stay tuned. :snacks:


Why? Got a fresh harvest of beets in?


----------



## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> 3db is double the power, is it not? Then wouldn't it follow that 10db is 3.33 times the power? Color me confused here.


1 watt = x dB
2 watts = +3 dB
4 watts = +6 dB
8 watts = +9 dB
10 watts'ish = +10dBs'ish

10 _times_ the power = 10 dB


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## MarkZ (Dec 5, 2005)

tspence73 said:


> 3db is double the power, is it not? Then wouldn't it follow that 10db is 3.33 times the power? Color me confused here.


No. dBpower = 10log(X/X0)

So 10dB is a ratio of 10.


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## shadowfactory (Oct 20, 2008)

t3sn4f2 said:


> Why? Got a fresh harvest of beets in?


Dwight on dating


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> 3db is double the power, is it not? Then wouldn't it follow that 10db is 3.33 times the power? Color me confused here.


Good lord man. Stop thinking so damn black/white.

Not everything can be plotted on a line graph.


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## 14642 (May 19, 2008)

tspence73 said:


> 3db is double the power, is it not? Then wouldn't it follow that 10db is 3.33 times the power? Color me confused here.


Tim,
Each 3dB increase is double the power. The second 3dB is 4 times the original and the third 3dB is twice the second, or 8 times the original. 

That's how exponents work.


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## SublimeZ (Jan 28, 2008)

tspence73 said:


> Color me confused here.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> 3db is double the power, is it not? Then wouldn't it follow that 10db is 3.33 times the power? Color me confused here.



Really? REALLY? You didn't know that decibels are a LOG SCALE while doing your masterful 'calculations?'
Do you see now why your logic is so retarded?

Go hook up your subs at 4 ohms now or a meteor made of hair and cat piss will esplode your house. 

READ NOW
Logarithmic scale - Wikipedia, the free encyclopedia
Logarithmic scale - Wikipedia, the free encyclopedia
Logarithmic scale - Wikipedia, the free encyclopedia


----------



## tspence73 (Oct 14, 2008)

shadowfactory said:


> Really? REALLY? You didn't know that decibels are a LOG SCALE while doing your masterful 'calculations?'
> Do you see now why your logic is so retarded?
> 
> Go hook up your subs at 4 ohms now or a meteor made of hair and cat piss will esplode your house.
> ...


Ooops. Sorry. :rockstar: My bad. I did know that. I just did my math wrong. I was rushed and getting ready for work, so I wasn't focusing. I am used to doubling power ever 3db when going up in watts, not down. DOH. I seriously did know that though. I goofed. It ultimately doesn't change my point, in fact it reinforces it, so it's not the biggest deal. So, chillax everyone. I know everyone likes to jump on me the minute I make mental errors, so you caught me slacking.


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> It ultimately doesn't change my point, in fact it reinforces it, so it's not the biggest deal.













:listenup:


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## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> Ooops. Sorry. :rockstar: My bad. I did know that. I just did my math wrong. I was rushed and getting ready for work, so I wasn't focusing. I am used to doubling power ever 3db when going up in watts, not down. DOH. I seriously did know that though. I goofed. It ultimately doesn't change my point, in fact it reinforces it, so it's not the biggest deal. So, chillax everyone. I know everyone likes to jump on me the minute I make mental errors, so you caught me slacking.


Ah! that's it, you fail. You've been exposed. No turning back now, there is no hope. It's all down hill from here.


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## tspence73 (Oct 14, 2008)

Here. Is this better:

1,200 = 0db
600 = -3db
300 = -6db
150 = -9db
75 = -12db

So, there ya go. :cwm15:


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## t3sn4f2 (Jan 3, 2007)

tspence73 said:


> Here. Is this better:
> 
> 1,200 = 0db
> 600 = -3db
> ...


Nope. Sorry, too late now. The cat's out of the bag!


----------



## shadowfactory (Oct 20, 2008)

tspence73 said:


> Here. Is this better:
> 
> 1,200 = 0db
> 600 = -3db
> ...


Is that for test tones? Cause its not like that for music.


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## t3sn4f2 (Jan 3, 2007)

Uh uh, off you go. Exiled to moderate your YSHSF forum only.


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## tspence73 (Oct 14, 2008)

Nice try in getting things off track guys. Back to the original argument. My subs. Are they suffereing from audible compression artifacts? If so. By how many db's. My math skillz at the moment are in paralysis. :surprised:


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> 3db is double the power, is it not? Then wouldn't it follow that 10db is 3.33 times the power? Color me confused here.


Math ownes you. Still pretending power compression doesn't exist in your corner of the world. Read that JBL tech article. As a matter of fact read all those tech articles. The one thing they all have in common - they all say that power compression affects all speakers. 

First you were arrogant and insulting to the people that suggested trying a 4 ohm load. Then you were arrogant toward me for pointing out the flaw in your "rebuttal." Now after piles of very scientific evidence about how power compression affects drivers (all drivers), you still reject it. So don't give us your BS that you want scientific evidence. You want to argue and reject anything we suggest. 

Rudeboy is right, you're some sort of joke; I can't just decide what type of joke you are, but either way its a bad joke.


----------



## MarkZ (Dec 5, 2005)

tspence73 said:


> Nice try in getting things off track guys. Back to the original argument. My subs. Are they suffereing from audible compression artifacts? If so. By how many db's. My math skillz at the moment are in paralysis. :surprised:


First you said no dee beez. Then you said one dB. We're still waiting for you to tell us how you've come up with these numbers.

Your ball.


----------



## tspence73 (Oct 14, 2008)

Jimi77 said:


> Math ownes you.


:shrug:



> Still pretending power compression doesn't exist in your corner of the world. Read that JBL tech article. As a matter of fact read all those tech articles. The one thing they all have in common - they all say that power compression affects all speakers.


To what degree is the question and you still haven't defined that. Is it an audible level or not? So far no one has given a method of finding that and I was given info from an engineer that as long as RMS ratings are obeyed, the resulting compression should be inaudible.



> First you were arrogant and insulting to the people that suggested trying a 4 ohm load.


Where was I arrogant? People needs to put things in perspective and quit taking things personal. Jeez.



> Then you were arrogant toward me for pointing out the flaw in your "rebuttal." Now after piles of very scientific evidence about how power compression affects drivers (all drivers), you still reject it. So don't give us your BS that you want scientific evidence. You want to argue and reject anything we suggest.


Again, I didn't reject that power compression exists but rather would like to know to what degree and how to calculate it? That would be nice.



> Rudeboy is right, you're some sort of joke; I can't just decide what type of joke you are, but either way its a bad joke.


Aw shaddup! :toilet:


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> Nice try in getting things off track guys. Back to the original argument. My subs. Are they suffereing from audible compression artifacts? If so. By how many db's. My math skillz at the moment are in paralysis. :surprised:



Of course your subs are suffering from audible compression artifacts, just like mine and everybody else's. If you read any of the tech articles (or perhaps they exceed your comprehension), then you'd know there is no way us to calculate the affect. You could calculate the affects by measuring for impedance with pink noise after warming up the coils.

Regardless of the affects of compression, you still have a giant hole in your FR and your method for addressing it is pretty much find the most difficult way to fix the problem. You have (most likely) have 2 problems - cancellation in the trunk and weak midbass output from the comps.

Luckily of me and most of the rest of the members here we know the way to address said problems.

Sub-bass cancellation - move the sub to the rear most location facing the rear and see if response improves (you should have done this 2 months ago when I first told you). 

Once you've confirmed it's a cancellation problem, then you have some choices:

1) Leave the enclosure at the back of the trunk.
2) Build FG enclosure(s)s behind the wheel wells, like the pic below. You might want to switch to a single high excursion sub (ie Fi Q, IDMax, JL w7, JBL wgti, etc) so you'll only need a single enclosure. 
3) Remove crappy 6x9s and fire a 4th order bandpass directly into the cabin.
4) Remove crappy 6x9s and go Infinite Baffle. 

Now the cancellation problem is solved, just pick up a set of comps that sound similiar to the Refs, but are capable of decent midbass output (ie Alpine Type X pros). Problems solved. Problems are best resolved using direct and proven methods.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> To what degree is the question and you still haven't defined that. Is it an audible level or not? So far no one has given a method of finding that and I was given info from an engineer that as long as RMS ratings are obeyed, the resulting compression should be inaudible.


I thought you said you don't just take people's word for it? I thought you said you required that people provide proof?

And since when is an "internet associate" an engineer?



> Again, I didn't reject that power compression exists but rather would like to know to what degree and how to calculate it? That would be nice.


I thought you already did calculate it?

Well, if you didn't, the best way to predict what it might be is to first figure out how much power you're delivering to the speaker, and then to figure out the geometrical configuration of the motor structure and materials involved. Alternatively, as Jimi mentions above, you can just measure it directly (although I'd probably use pure tones because it might be easier for you to measure the power content). Be careful you don't go too high with it though.


----------



## tspence73 (Oct 14, 2008)

MarkZ said:


> First you said no dee beez. Then you said one dB. We're still waiting for you to tell us how you've come up with these numbers.
> 
> Your ball.


I can't believe the compression is THAT bad to the point of running around starting fights about it. Escpecially when there is no true method of determining it other than if the manufacturer tested for it. So, I will try to figure it out but it looks like a dead end until someone shows some data.


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## shadowfactory (Oct 20, 2008)

Jimi77 said:


> THE HOLY LIGHT OF JESUS CHRIST



Do all of this right now. This answers every question and the thread must now be closed.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> :shrug:
> 
> To what degree is the question and you still haven't defined that. Is it an audible level or not? So far no one has given a method of finding that and I was given info from an engineer that as long as RMS ratings are obeyed, the resulting compression should be inaudible.


An engineer told you that. Did you see his degree? His word trumps the word of numerous other engineers and the entire audio community? Nobody has given you a method for finding the impact? I posted a paper that was all about calculating the effects - obviously not reading the links or this is way over your head, either way that leaves you stuck with having to trust us doesn't it?



tspence73 said:


> Where was I arrogant? People needs to put things in perspective and quit taking things personal. Jeez.


Oh really calling Shawdow Factory stupid wasn't arrogant and insulting? (post #183) 



tspence73 said:


> Again, I didn't reject that power compression exists but rather would like to know to what degree and how to calculate it? That would be nice.


What you really said: _There is usually little to no compression on speakers that play within their stated RMS rating. The RE SE 12's have a 600-watt RMS rating EACH. That marries perfectly to the amp's 1200-watt RMS peak output. THERE IS NO POWER COMPRESSION GOING ON HERE. Please STOP_

That's you denying that power compression exists. Of course you didn't ask about how to calculate since you were under the impression that it doesn't exist. It wasn't until it was beaten into your head that you finally acknowledged power compression's existence. I posted a link to an entire paper on how to measure the affects, clearly you aren't reading the papers or you're no comprehending the information contained within.


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## tspence73 (Oct 14, 2008)

MarkZ said:


> I thought you said you don't just take people's word for it? I thought you said you required that people provide proof?
> 
> And since when is an "internet associate" an engineer?


The associate relayed the info after speaking with an internal engineer. I trust they know what their speakers are capable of.



> I thought you already did calculate it?


It's based on the assumption that the heat of the coil is not reaching 200 degrees or some outrageous temp. It's highly unlikely to be getting that hot.



> Well, if you didn't, the best way to predict what it might be is to first figure out how much power you're delivering to the speaker, and then to figure out the geometrical configuration of the motor structure and materials involved. Alternatively, as Jimi mentions above, you can just measure it directly (although I'd probably use pure tones because it might be easier for you to measure the power content). Be careful you don't go too high with it though.


No thanks. I've had enough of abusing my speakers with tones. I know the limits of my drivers with the voltage settings and am ready to tweak this system.


----------



## Oliver (Jun 25, 2007)

Got $20.00 ? :z:

AES E-Library: Heat Dissipation and Power Compression in Loudspeakers by Button, Douglas J.

AES E-Library: Heat Dissipation and Power Compression in Loudspeakers by Button, Douglas J.
Heat Dissipation and Power Compression in Loudspeakers
JAES Volume 40 Issue 1/2 pp. 32-41;* February 1992*
In the professional audio market today there is a variety of transducers with high power ratings. As these drivers generally are less than 5% efficient, they convert almost all of their input power to heat. How this heat is dealt with is discussed, and conclusions about power compression effects in a variety of popular designs are revealed.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> The associate relayed the info after speaking with an internal engineer. I trust they know what their speakers are capable of.


And they provided zero proof. None. They alluded to a test that they don't even run. You said before that you require proof.

And as it turns out, the internet associate's message to you was wrong. And directly at odds with Dan Wiggins' email that you posted in the same post.



> It's based on the assumption that the heat of the coil is not reaching 200 degrees or some outrageous temp. It's highly unlikely to be getting that hot.


It may not be. Or then again, maybe it is. You assumed it wasn't because, for some reason, you believed that the solder on the speaker terminals would melt before it even got that hot. Hopefully you've abandoned that belief by now, especially after I posted a reference to a peer-reviewed article that specifically mentioned 200 degrees.

But it any case, even if it isn't reaching 200 degrees celsius, it's still undoubtedly getting pretty hot. And so power compression IS at play. As I said to you many many posts ago, the question is HOW MUCH is it a factor. None of us really knows, mostly because we don't know your listening habits. But I suspect that if you're driving those subwoofers hard, it could be pretty substantial.



> No thanks. I've had enough of abusing my speakers with tones. I know the limits of my drivers with the voltage settings and am ready to tweak this system.


Suit yourself. Although if you're afraid of frying your speakers doing a power compression test of realistic power levels, then you shouldn't dismiss power compression so readily. Power compression should set in well before thermal failure.


----------



## MarkZ (Dec 5, 2005)

a$$hole said:


> Got $20.00 ? :z:
> 
> AES E-Library: Heat Dissipation and Power Compression in Loudspeakers by Button, Douglas J.
> 
> ...


PS - I have the pdf of this one. Hint.


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> An engineer told you that. Did you see his degree? His word trumps the word of numerous other engineers and the entire audio community? Nobody has given you a method for finding the impact? I posted a paper that was all about calculating the effects - obviously not reading the links or this is way over your head, either way that leaves you stuck with having to trust us doesn't it?


Aren't we putting too fine a point on this whole thing? If you don't know, just say you don't know. There is no shame in not knowing. 




> Oh really calling Shawdow Factory stupid wasn't arrogant and insulting? (post #183)


Sometimes he is stupid. 




> What you really said: _There is usually little to no compression on speakers that play within their stated RMS rating. The RE SE 12's have a 600-watt RMS rating EACH. That marries perfectly to the amp's 1200-watt RMS peak output. THERE IS NO POWER COMPRESSION GOING ON HERE. Please STOP_


I was going on articles I read stating that power compression is normally caused from a driver heating up to it's thermal limits usually by coming close to or exceeding it's RMS wattage. So, I'm not an expert on power compression but then, neither are you because neither of us have hard numbers to concern ourselves with.



> That's you denying that power compression exists.


I didn't say it 'didn't exist'. I said I have my amp set to a very conservative output and power compression very likely isn't a major concern.



> Of course you didn't ask about how to calculate since you were under the impression that it doesn't exist.


I was under the impression that power compression isn't a problem until you push the driver near it's thermal limits.



> It wasn't until it was beaten into your head that you finally acknowledged power compression's existence.


Cha' right. :rifle:



> I posted a link to an entire paper on how to measure the affects, clearly you aren't reading the papers or you're no comprehending the information contained within.


Okay, then give me a rough estimate of the power compression of my well known RE SE 12's at the wattage I'm running it at. I'm interested in your opinion on this. It's my opinion based on the general info I've read that unless thermal limits are reached, power compression is really a big concern.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> I can't believe the compression is THAT bad to the point of running around starting fights about it. Escpecially when there is no true method of determining it other than if the manufacturer tested for it. So, I will try to figure it out but it looks like a dead end until someone shows some data.


I LINKED TO a PAPER WHO'S ENTIRE PURPOSE WAS TO DEMONSTRATE HOW YOU CAN MEASURE THE EFFECTS. THEY PROVIDED A CHART AND EVERYTHING!!!!  Just because you don't know how to measure something, doesn't mean it doesn't exist. I didn't have to land the mars rover on Mars to accept that they've landed a rover on Mars.

It's not bad? You have companies patenting venting/cooling methods and slews of audio engineers writing papers on compression, it's affects, cooling methods, current regulated amps, etc, etc, etc. 

Mark Z, I said pink noise because we're looking for impedance in the bandpass. A test tone at or near the sub's FS would have a higher impedance and could throw off the calculations as could a test tone at or near the sub's impedence trough. He doesn't need test tones because after measuring for impedance, he can calculate for his power/power loss because he has voltage (and impedance). The charts in the paper provide the formula's to calculate VC temp.

Hell who needs the charts or calculations. Slam your subs with some bass heavy music or test tones, then open the box and grab the motor - it's hot and that's a big huge magnet that's effective at radiating heat away. All that heat is just what is being radiated by the VC, of course the VC is significantly hotter. Feel the heat coming from the pole vent. That's pretty convincing evidence that VC's get freaking hot. Hell a with 1200rms amp, tspence could arc weld some VCs, but for some reason he needs some sort of absolute proof. 

http://www.diymobileaudio.com/forum/newreply.php?do=newreply&p=624541


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## tspence73 (Oct 14, 2008)

MarkZ said:


> PS - I have the pdf of this one. Hint.


Are my speakers on the list? Give up the goods man. I ain't payin' no $20. :coolgleamA:


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## MarkZ (Dec 5, 2005)

Jimi77 said:


> Mark Z, I said pink noise because we're looking for impedance in the bandpass. A test tone at or near the sub's FS would have a higher impedance and could throw off the calculations as could a test tone at or near the sub's impedence trough. He doesn't need test tones because after measuring for impedance, he can calculate for his power/power loss because he has voltage (and impedance). The charts in the paper provide the formula's to calculate VC temp.


Jimi, that's the same reason I suggested tones.  Of course, you can do it both ways, I just think the calcs will be easier with a sine. The reactive component of the impedance should be a constant here, and I think with a single tone it's easier to nail down than with a broadband signal.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> Are my speakers on the list? Give up the goods man. I ain't payin' no $20. :coolgleamA:


No, it's a modeling paper. It's not a list of specs. If you'd like to read it anyway, shoot me a PM.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> Sometimes he is stupid.



http://www.demotivateus.com/posters/cobra-commander-demotivationalmoral-poster-****-off.jpg


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## Oliver (Jun 25, 2007)

tspence73 said:


> Are my speakers on the list? Give up the goods man. I ain't payin' no $20. :coolgleamA:


Cheap azz biatch :mean:


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> I was going on articles I read stating that power compression is normally caused from a driver heating up to it's thermal limits usually by coming close to or exceeding it's RMS wattage. So, I'm not an expert on power compression but then, neither are you because neither of us have hard numbers to concern ourselves with.
> 
> I was under the impression that power compression isn't a problem until you push the driver near it's thermal limits.
> 
> Okay, then give me a rough estimate of the power compression of my well known RE SE 12's at the wattage I'm running it at. I'm interested in your opinion on this. It's my opinion based on the general info I've read that unless thermal limits are reached, power compression is really a big concern.



I'm not an "expert," that's why I referred you to the people are experts in the field so you could learn from their work in the field. However, I am smart enough to know that I can't know much it's effecting you without actually measuring it or with data from RE regarding the temps they rate their coils for. Feel free to drive your arse out to Denver and I'll be happy to build a little voltage dividing network and measure for the impedance. You're a smart guy why can't you measure for it yourself. Since 200C isn't too uncommon in subs, feel free to use that figure and do some more calculations.


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## 14642 (May 19, 2008)

Just measure the frequency response of your sub at some specific output power (or voltage). It's best to use a sine sweep that isn't super fast. Then, increase the output of the amplifier by turning up the volume on the radio so the output voltage of the amp has increaseby 3dB. The output of the woofer should track the output of the amplifier and increase by 3dB. Continue doing this until you reach a point at which the output of the sub doesn't increase by 3dB. That'll give you an idea of how much power you have to provide to reach a point where power compression can be measured. Whether you can hear this will have a great deal to do with the audio that's reproduced. For your subs, it's likely that you'll be listening at levels loud enough to It's easiest to see this if you have an analyzer than can measure and display 2 channels simultaneously--one for the mic and one for the output of the amplifier.


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## Oliver (Jun 25, 2007)

Andy Wehmeyer said:


> It's easiest to see this if you have an analyzer than can measure and display 2 channels simultaneously--one for the mic and one for the output of the amplifier.


use the money you saved on the AES paper:juggle2:


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## Knobby Digital (Aug 17, 2008)

or get a BSEE and STFU.


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## falkenbd (Aug 16, 2008)

> = 360 watts average in music according to the pre-amp volume setting of 75% of max (as it was set with my 0db test tone and DMM).


AVERAGE? on music? - your pre-amp volume setting of 75% max told you so?????


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## Jimi77 (Jul 4, 2005)

MarkZ said:


> Jimi, that's the same reason I suggested tones.  Of course, you can do it both ways, I just think the calcs will be easier with a sine. The reactive component of the impedance should be a constant here, and I think with a single tone it's easier to nail down than with a broadband signal.


I guess as long as the baseline and warm test are both done the same way it shouldn't matter. I could just see tspence measuring at close to FS, getting high impedance figures, telling us his sub's impedance is 2 ohms instead of 1 ohms and that RE sent him the wrong subs, etc. Then it would take us 7 pages of arguing to explain that his sub's are really 1 ohm. :cwm33:


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## tspence73 (Oct 14, 2008)

falkenbd said:


> AVERAGE? on music? - your pre-amp volume setting of 75% max told you so?????


We already hashed that I did my math wrong. I've been beaten about the head and shoulders then dragged by horses through the streets already. :bash: :dead_horse: Then beheaded :behead: and my body burned. :z: It was something akin to the Passion of the Christ only more bloody. :whip:

The average wattage would actually be much lower, probably closer to 100-watts and the 4 coils sharing 100-watts (25-watts each) is not going to heat up the subs that much. So, I'm still having my doubts that power compression is occurring on an audible level.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> The average wattage would actually be much lower, probably closer to 100-watts and the 4 coils sharing 100-watts (25-watts each) is not going to heat up the subs that much. So, I'm still having my doubts that power compression is occurring on an audible level.


Proof?


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## Knobby Digital (Aug 17, 2008)

Cutt the **** Spense. You've been outed as someone who hasn't passed junior high algebra.

Yesterday I was sitting in traffic listening to the Bose system in my woman's car.

If you really want something like that, you need to just get a good active xover, a comprehensive EQ, and get your **** tuned by the finest shop in town.


Did it ever dawn on you that for efficiency they use cheap ass drivers and amps, passive xovers designed for the application, and have skilled R&D tune the hard EQ that's in everyone of those systems?

Of course you couldn't derive that Andy W.'s post on the subject and my experiences that I posted. That would have taken too much effort.


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## Knobby Digital (Aug 17, 2008)

And they're also almost exclusively found in cars with a far lower noise floor than a Nissan Sentra.


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## falkenbd (Aug 16, 2008)

> The average wattage would actually be much lower, probably closer to 100-watts and the 4 coils sharing 100-watts (25-watts each) is not going to heat up the subs that much. So, I'm still having my doubts that power compression is occurring on an audible level.


So why all this fuss about 1 ohm over 4 ohms???

Sounds to me like a 4 ohm load set with a little gain overlap would give you the same amount of bass...




All of that aside, you need to stop thinking so much and listen... Let what you hear dictate what is best, not all this stuff that pops into your head... If you would have taken 4 minutes to turn the sub box around, you would have seen that it sounded better - instead of arguing about it all day long.


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## tspence73 (Oct 14, 2008)

MarkZ said:


> Proof?


Okay, I'll do better this time. Let's see if you guys can understand now.

I have this saved in my photobucket from a previous post. It's a prime example of a modern pop/rock/R&B recording:











Okay, notice the average level is at -10.9db.

Now, going by the scale for decibles. The average wattage output from an amp tuned to peak at 1200 watts @ 0db, you should end up with:

1,200 watts = 0db
600 watts = -3db
300 watts = -6db
150 watts = -9db
Somewhere in this section <------------------ likely around 100-120 watts average.
75 watts = -12db

There. That should be pretty straight forward. Not precise to the watt but a pretty good ballpark number. With 4 coils sharing that wattage, my *guess* would be that thermal compression would be inaudible. Especially since much smaller coils in speakers of smaller size don't have audible thermal compression until many more continuous watts are applied to it. 

That JBL 2020H driver that was linked earlier by Jimi77 is a prime example, that it doesn't start to approach audible issues until over 100-watts continuous with a SINGLE coil that should be somewhat comparable to each coil in my sub in that they are 300-watts RMS continuous. The two drivers are different enough that a parallel cannot be drawn between them with total certainty.

I will try to do the calculations on the supplied methods by others to verify but it's a pretty good assumption that my subs aren't audibly effected by power compression at any volume, even the peak volume setting I would use (75% of max). 

So, throw your computers. :listenup:
Spray your mean words. :argue:
Laugh all you want. :laugh:

It's lookin' like my subs aren't going to be much effected by power compression. We shall see.


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## benny (Apr 7, 2008)

I hate to do this...so you realize that of the 100 watts you send to your subs, avg, that 95-97 watts go to directly heating the coils? That only 3-5 watts make it out as music?


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## tspence73 (Oct 14, 2008)

falkenbd said:


> So why all this fuss about 1 ohm over 4 ohms???
> 
> Sounds to me like a 4 ohm load set with a little gain overlap would give you the same amount of bass...
> 
> ...


Settle down Beavis. I will eventually get around to trying this when I have my comps/midbasses/active crossover done and I'm tweaking. Then I'll have the idle time to try out the silly stuff.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> Okay, I'll do better this time. Let's see if you guys can understand now.
> 
> I have this saved in my photobucket from a previous post. It's a prime example of a modern pop/rock/R&B recording:
> 
> ...


Didn't I explain to you earlier why your insistence that there are 4 independent coils is a red herring? You don't have four motors. You have two motors. You have two gaps. For all intents and purposes, you have two coils -- one per speaker. So taking an example speaker and multiplying its capabilities by four to try to fit your situation simply doesn't work.

Anyway, back to the issue. How come you don't consider 100+ watts of power (or higher during portions of the song) to be capable of heating your coils? Ever touch a 100w light bulb?

Seriously, dude, there's this well-established phenomenon called power compression. It's all over the place. You, by your very own admission, are running lots of power to your subs (and you've defended using so much power against critics who have suggested configurations that result in less power). So why is it that you think that your high power setup is immune to power compression? In what types of setups do you think power compression has an effect?

PS: R = R0*[1+A*(T-T0)]


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## tspence73 (Oct 14, 2008)

benny said:


> I hate to do this...so you realize that of the 100 watts you send to your subs, avg, that 95-97 watts go to directly heating the coils? That only 3-5 watts make it out as music?


That is probably due to lack of efficiency? The coils on subs are usually made to take and dissapate heat. The way I'm setting these subs is VERY conservative. These subs are designed for abuse on a whole other level than the easy load I'm putting on them.


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## tspence73 (Oct 14, 2008)

icehole said:


> And they're also almost exclusively found in cars with a far lower noise floor than a Nissan Sentra.


Have my goals been ignored? I've never said my Sentra was as quiet as a luxury car. I've been saying the very same thing you have. That's why in phase 2 of my system I will address acoustics with damper, sludges, new tires, VE damper on body panels, firewall treatments, roof treaments, insulation, and more. My acoustic treatments and mods in total will likely exceed my equipment costs.

Anyway, you heard a Bose system in a car. It's pretty good isn't it? Most people assume ahead of time that it sounds as bad/lame as their home speaker systems. Their car system actually has decent fidelity. It's not 'blow the doors down' powerful, nor is it going to win any awards with the widest dynamics, but for tonality it's right there. The reproduction sounds closer to the real thing than most setups. I give it high marks when combined with the quiet cabin of a luxury car.


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## benny (Apr 7, 2008)

thats all i wanted to say, I'm not posting in one if your threads *three* times.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> Have my goals been ignored? I've never said my Sentra was as quiet as a luxury car. I've been saying the very same thing you have. That's why in phase 2 of my system I will address acoustics with damper, sludges, new tires, VE damper on body panels, firewall treatments, roof treaments, insulation, and more. My acoustic treatments and mods in total will likely exceed my equipment costs.


I suppose a luxury car with no stereo would have no deadening at all, then.

And if you're referring to the 17''s that I assume will be an upsize, do you understand what affect that wil have on your ''goals''?


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## pontiacbird (Dec 29, 2006)

wow, i read the first page and last page....


who cares about 119db?




quit all this typing at once....install your sh!t


does it sound good? If yes, stop here.

If no, try again.

Simple.



[/thread]


once again, you demonstrated how you take something so seemingly simple, and make it so complex and convoluted that it is basically FUBAR'd.....

don't do this....


and power compression...sadly, as you have realized......is a truth/fact.....

maybe it's the point where we should 'turn down the radio' before blowing out our eardrums.....


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> Anyway, you heard a Bose system in a car. It's pretty good isn't it? Most people assume ahead of time that it sounds as bad/lame as their home speaker systems. Their car system actually has decent fidelity. It's not 'blow the doors down' powerful, nor is it going to win any awards with the widest dynamics, but for tonality it's right there. The reproduction sounds closer to the real thing than most setups. I give it high marks when combined with the quiet cabin of a luxury car.


I've owned a couple cars with Bose stereos and drive one on a regular basis. My opinion is exactly what I've said in this thread.

Sounds like a well tuned cheap system. Which to me is better than a poorly tuned, or worse untuneable, expensive one.

Yes, there's a lack of output, bass guitar sounds like a human hum rather than an instrument, and mids lack detail, but I'll take that over doing a mini-tune on 2-5 bands of headunit EQ on a nearly track-by-track basis and hope that the enough of freqs you need are tuneable.

You completely missed the point of those posts, which clearly state that if that's what you're after, not only have you overspent, but you're taking a terribly wrong approach.


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## Jimi77 (Jul 4, 2005)

What this comes down to folks is that we, including a few people who work in the industry, Dan Wiggins, numerous audio engineers & designers, multiple EEs are all wrong and tspence and some internet audio consultant are right. :thumbsup:


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## Jimi77 (Jul 4, 2005)

icehole said:


> You completely missed the point of those posts, which clearly state that if that's what you're after, not only have you overspent, but you're taking a terribly wrong approach.


Agreed. Like I said, throw in some Alpine Type X Pros and mount the subs IB and he'll have plenty of midbass up-front and the gapping hole in his frequency response will be gone. Problem solved for ~$350, plus the Alpine midbass is pretty shallow making for an easier install.


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## Rudeboy (Oct 16, 2005)

Jimi77 said:


> What this comes down to folks is that we, including a few people who work in the industry, Dan Wiggins, numerous audio engineers & designers, multiple EEs are all wrong and tspence and some internet audio consultant are right. :thumbsup:


Tspence is always right - by definition.


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## capnxtreme (Feb 5, 2008)

Why do we even play with this clown anymore?  It's not even funny anymore, just pathetic and sad.

tspence, for the love of god, go get laid.


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## Knobby Digital (Aug 17, 2008)

capnxtreme said:


> tspence, for the love of god, go get laid.


I honestly once almost compared his lack of desire to even try his comps active to watching porn vs. getting laid, but I figured he may very well be a virgin.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> It's lookin' like my subs aren't going to be much effected by power compression. We shall see.



_The inherent inefficiency of direct-radiating moving-coil loudspeakers (typically only 1–2%) means that considerable electrical power is dissipated in the coil resistance. Just as with the incandescent light bulb, little of the input energy is put to good use; the rest appears as heat. _
Stereophile: Hot Stuff: Loudspeaker Voice-Coil Temperatures

Again who cares what knowledgable experts say.  You ask for advice only to reject it, then you ask for proof only to reject it. Good luck with your crap system.


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## tspence73 (Oct 14, 2008)

MarkZ said:


> Anyway, back to the issue. How come you don't consider 100+ watts of power (or higher during portions of the song) to be capable of heating your coils? Ever touch a 100w light bulb?


Yeah, but that's a thin filament that is supposed to get hot because it's a small amount of metal. Remember that thin wires get hot when you pass enough current through them. Increase the amount of metal and you increase the amount of heat disapation and heat absorption.


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## aztec1 (Jun 13, 2008)

tspence73 said:


> Yeah, but that's a thin filament that is supposed to get hot because it's a small amount of metal. Remember that thin wires get hot when you pass enough current through them. Increase the amount of metal and you increase the amount of heat disapation and heat absorption.


That's not entirely true, it just takes longer given the same current.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> Yeah, but that's a thin filament that is supposed to get hot because it's a small amount of metal. Remember that thin wires get hot when you pass enough current through them. Increase the amount of metal and you increase the amount of heat disapation and heat absorption.


You've got to be kidding. I suppose you don't know what a voice coil is made of:

_To generate sufficient force, the wire in a moving-coil driver must be many meters long and so is wound into a coil, archaically termed the voice-coil. To keep this coil from being too large and heavy, the wire must be *thin*._

Stereophile: Hot Stuff: Loudspeaker Voice-Coil Temperatures

Clearly you aren't bothering to read the information that you requested. Why did you request the info if you weren't interested in reading it? :huh:


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> Yeah, but that's a thin filament that is supposed to get hot because it's a small amount of metal. Remember that thin wires get hot when you pass enough current through them. Increase the amount of metal and you increase the amount of heat disapation and heat absorption.


Why not just try running them hard for an hour, and then sticking your finger in the pole vent?

Before you say it's too much work to turn 8 screws because someone should just be able to give you an answer, imagine the joys of learning by EXPERIENCE!!!



Seriously, if you love car audio so much, how come you have no curiosity and so much fear? I mean, not turning your speaker box around in your trunk? Every person I went to HS with turned their subs every which way in their trunks looking for more output since their funds were limited and couldn't just go out and buy better equipment. This is how people learn things.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> Yeah, but that's a thin filament that is supposed to get hot because it's a small amount of metal. Remember that thin wires get hot when you pass enough current through them. Increase the amount of metal and you increase the amount of heat disapation and heat absorption.


That's right. It was an analogy. But how come you didn't answer my question and just cherry-picked this one to divert attention away from it? 

Again: why do you think that 100+ watts of average power (and much higher transients) are something to scoff at? And what makes you think that speakers have to take a lot more than that to be susceptible to power compression?


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> You've got to be kidding. I suppose you don't know what a voice coil is made of:
> 
> _To generate sufficient force, the wire in a moving-coil driver must be many meters long and so is wound into a coil, archaically termed the voice-coil. To keep this coil from being too large and heavy, the wire must be *thin*._
> 
> ...


My point is, thin or not, it's MORE material, far more, than in a light bulb. 100-watts to the coils as well as the thermal cooling for that coil makes it far less likely to get as hot as a light bulb.


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## tspence73 (Oct 14, 2008)

MarkZ said:


> That's right. It was an analogy. But how come you didn't answer my question and just cherry-picked this one to divert attention away from it?
> 
> Again: why do you think that 100+ watts of average power (and much higher transients) are something to scoff at? And what makes you think that speakers have to take a lot more than that to be susceptible to power compression?


In this thread there was a direct comparison that could be made with a driver that gave a rating for it's own compression that seemed to indicate 100-watts wasn't bad, and that was for only 1 coil, not 4 like in my two RE SE subs. The chances that the two subs are having audible compression at my settings would be unlikely. That is ALL that is being argued by me here. I don't have total proof, yet, but it seems more likely I'm right than wrong on this. Especially considering the manufacturer built the subs for far more of a beating than I'll ever give them.


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## tspence73 (Oct 14, 2008)

aztec1 said:


> That's not entirely true, it just takes longer given the same current.


There is a whole section of additional mass acting like a heatsink for the coils PLUS moving air that is channeled specifically for cooling the coils. The subwoofers (and yes, that's more than one) is not likely to get as hot as a light bulb given the same 100-watts. It's not much different than computer processors and cooling them. Modern processors on computers and cooling them is a great example. If I stick a bunch of heat conducting mass on a PC processor and air cool it, it stays far cooler than a processor without any cooling. People here who build their own PCs know that modern processors must have cooling and the difference in temp with cooling is dramatic.


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## Jimi77 (Jul 4, 2005)

icehole said:


> Why not just try running them hard for an hour, and then sticking your finger in the pole vent?
> 
> Before you say it's too much work to turn 8 screws because someone should just be able to give you an answer, imagine the joys of learning by EXPERIENCE!!!


Already suggested, but we're talking a person who is still battling trunk cancellation after being told move/reorient the sub 2 months ago.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> ...


Maybe in a perfect world where titties didn't eventually sag and >100% efficiency existed outside of the Chinese labor force, Spense, but that's not where we live.

You gotta give to get. Work, and I'm not talking about punching a clock, is a reality of life. It has by-products. Accept it.



I'm sorry about it, too.


----------



## Rudeboy (Oct 16, 2005)

icehole said:


> Seriously, if you love car audio so much, how come you have no curiosity and so much fear? I mean, not turning your speaker box around in your trunk? Every person I went to HS with turned their subs every which way in their trunks looking for more output since their funds were limited and couldn't just go out and buy better equipment. This is how people learn things.


This is such an important point. This guy has raised "spoon feeding" to an absurd new level. 



MarkZ said:


> That's right. It was an analogy. But how come you didn't answer my question and just cherry-picked this one to divert attention away from it?


SOP. This thread is now about light bulbs. We all keep thinking that if we just make the explanation clear enough, he will finally understand and start behaving like a reasonable person. At this point it's obvious that he likes it inside the tunnel.


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## t3sn4f2 (Jan 3, 2007)

Light Bulb Fun Fact! :idea3: :jester:

The coiled filament on a light bulb is made up of a coiled up filament itself, a "coiled coil". Uncoiled, it's actually 22 inches long!


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## falkenbd (Aug 16, 2008)

tspence73 said:


> Settle down Beavis. I will eventually get around to trying this when I have my comps/midbasses/active crossover done and I'm tweaking. Then I'll have the idle time to try out the silly stuff.


You must spend at least an hour a day posting on this forum, and who knows how many others... You will eventually get around to spending 3 minutes turning your subs around???

Like I said, maybe you could stop wasting your time talking about stuff, and just try it....


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## MarkZ (Dec 5, 2005)

tspence73 said:


> In this thread there was a direct comparison that could be made with a driver that gave a rating for it's own compression that seemed to indicate 100-watts wasn't bad, and that was for only 1 coil,


100w, average power? Proof?



> not 4 like in my two RE SE subs.


I think you mean 2 coils in your 2 subs. I explained why, twice now.



> The chances that the two subs are having audible compression at my settings would be unlikely.


Proof?



> That is ALL that is being argued by me here. I don't have total proof, yet, but it seems more likely I'm right than wrong on this.


That's because you have issues comprehending what you read. And you've shown that you have NO interest in learning about the subject. I offered you the chance to read peer-reviewed papers on the issue (in pdf format), but haven't received a PM from you.



> Especially considering the manufacturer built the subs for far more of a beating than I'll ever give them.


They did? They rate their subs at 600w and you're running the pair with a 1200w amp.


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## tspence73 (Oct 14, 2008)

MarkZ said:


> 100w, average power? Proof?


The specs listed on the link to the JBL speaker show a spec for compression at 150w continuous output as 1.7db. That is barely audible and for 100-watts, if you scale it, we're talking about a nearly inaudible (if not, then inaudible) power compression on a driver that has a single/smaller coil. Again, that's for 1 coil, not four. And although a dual voice coil uses a single driver, it is still a dual coil speaker. That's two different coils taking heat. If it makes you feel better, you can sum the total power handling of the two coils together. It will work the same either way you look at it.

Here are your specs:
Power Compression4:
at -10 dB power (30 W): 0.5 dB
at -3 dB power (150 W): 1.7 dB
at rated power (300 W): 2.8 dB

Here is your link, as provided by Jimi77 earlier:
http://www.jblpro.ru/pdf/2020H.PDF




> They did? They rate their subs at 600w and you're running the pair with a 1200w amp.


A 1200-watt amp that is set lower than almost anyone will set it at. 1200 watts is only reached on a 0db peak. The average wattage output I'm setting it at is about 1/10th the amp's RMS rating. Also, 1/10th the subs' total RMS rating.


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## falkenbd (Aug 16, 2008)

tspence73 said:


> The average wattage output I'm setting it at is about 1/10th the amp's RMS rating. Also, 1/10th the subs' total RMS rating.


wow...


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## MarkZ (Dec 5, 2005)

tspence73 said:


> The specs listed on the link to the JBL speaker show a spec for compression at 100w continuous output.


Over how long? And how high were the transients? Not sure what kind of music you're listening to, but I betcha a dollar there are crescendos of some sort.



> Again, that's for 1 coil, not four. And although a dual voice coil uses a single driver, it is still a dual coil speaker. That's two different coils taking heat. If it makes you feel better, you can sum the total power handling of the two coils together. It will work the same either way you look at it.


Right it's a "600w" coil no matter how you look at it. Calling it two coils is misleading when discussing thermal properties. Hell, you could tap off the same coil 20 times and that doesn't mean you can say "but geez! there are 20 coils in there! they can withstand more than a single coil!" The reality is that the DVC configuration is only useful from an electrical perspective. Thermally, we're talking about the same VC mass that you'd otherwise use to achieve the same t/s params, and the same motor structure. So bringing up the number of coils is useless. If you want to compare it with other speakers, compare the mass of the coils, the width of the gap, and the geometry of the motor in general.



> A 1200-watt amp that is set lower than almost anyone will set it at. 1200 watts is only reached on a 0db peak.


What makes you think that the manufacturer sets its ratings with the assumption that people are going to clip the **** out of their amps? If their ratings are genuine, and they say "600w", then that probably means listening to music with a 600w amplifier. 

Of course, we don't really KNOW whether or not that "600w" figure is genuine. It probably doesn't mean "600w 100% duty cycle for 2 hours", and I'm almost certain it doesn't mean "600w average, but with big transients corresponding to loud parts of the musical passage".



> The average wattage output I'm setting it at is about 1/10th the amp's RMS rating. Also, 1/10th the subs' total RMS rating.


Show me "proof" that they're measuring their ratings the same way you're arriving at the above figures.

Use your brain for a minute. You're saying that these subs will handle a 12000 (twelve THOUSAND) watt amp with transients (during portions of the song that are near 0dB) that use every bit of the amp's capabilities. Do you honestly believe that?


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## capnxtreme (Feb 5, 2008)

tspence73 said:


> Again, that's for 1 coil, not four.


Are you ****ing serious?


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## tspence73 (Oct 14, 2008)

MarkZ said:


> Over how long? And how high were the transients? Not sure what kind of music you're listening to, but I betcha a dollar there are crescendos of some sort.


Of course. But I gave you numbers based on modern highly compressed music at -10db average. That's around 1/10th the wattage output of the RMS rating of the amp with the way I set it.



> Right it's a "600w" coil no matter how you look at it. Calling it two coils is misleading when discussing thermal properties. Hell, you could tap off the same coil 20 times and that doesn't mean you can say "but geez! there are 20 coils in there! they can withstand more than a single coil!" The reality is that the DVC configuration is only useful from an electrical perspective. Thermally, we're talking about the same VC mass that you'd otherwise use to achieve the same t/s params, and the same motor structure. So bringing up the number of coils is useless. If you want to compare it with other speakers, compare the mass of the coils, the width of the gap, and the geometry of the motor in general.


As I said, you could look at it either way (as one or two coils) but the math and the thermal handling will come out the same. So, I don't see the point in wasting time on semantics.



> What makes you think that the manufacturer sets its ratings with the assumption that people are going to clip the **** out of their amps? If their ratings are genuine, and they say "600w", then that probably means listening to music with a 600w amplifier.


I'm sure they don't but the 1200-watt RMS rating is set by Cadence as a full-duty tone at it's RMS. For what length of time, I'm not sure.



> Of course, we don't really KNOW whether or not that "600w" figure is genuine.


Ask RE-Audio. They would know. I'm assuming they mean it. They advertise that these subs are built for abuse. Many internet videos of these subs show abuse FAR FAR beyond anything my settings will produce. I assure you.



> It probably doesn't mean "600w 100% duty cycle for 2 hours", and I'm almost certain it doesn't mean "600w average, but with big transients corresponding to loud parts of the musical passage".


600-watts RMS, 1200-watts peak, per sub. So, yes, I do think that's what they are intending to say. Again, for what length of time? I couldn't know but that is the rating. My settings are for a full-duty tone to reach 1200-watts, which would be a "peak" output.



> Show me "proof" that they're measuring their ratings the same way you're arriving at the above figures.


I'm just going on the ratings. Other people posted videos on the web showing some outrageous excursions and outputs from these subs on a level I'm not even attempting. These subs in the right setups can get upwards of the 140'sdb of SPL. My PEAK is for only 119db which will only be reached if I crank my volume as high I dare (75% of max) and a CD plays some bass notes briefly at 0db peak. My settings are very conservative. I'm not too worried about power compression. Although, when I have time after Christmas and am not at work or working on my car, I'll figure out what my thermal compression losses likely are.



> Use your brain for a minute. You're saying that these subs will handle a 12000 (twelve THOUSAND) watt amp with transients (during portions of the song that are near 0dB) that use every bit of the amp's capabilities. Do you honestly believe that?


No, that's not what I meant. I either mis-typed my thoughts or maybe you didn't understand what I meant. I MEANT my average wattage output will be 1/10th the RMS capability of the sub amp and subwoofer due to the average output of the music and that the amp is set not to clip at all. I certainly couldn't set music's average to 1200-watts. That's retarded. I could definitely set the amp to clip by a good margin and probably not hear the distortion (which is what the vast majority of people with amps and subs are doing). I'm just not setting my amp that way. My system's bass is pretty tame sounding for a 1200-watt amp and two 12's.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> Here are your specs:
> Power Compression4:
> at -10 dB power (30 W): 0.5 dB
> at -3 dB power (150 W): 1.7 dB
> at rated power (300 W): 2.8 dB


I have to say, I'm baffled as to why you think your speakers are more immune to power compression than these speakers are. Yeah, yeah, I know, it has more taps on the voice coil. But I think (I hope) you understand now why that's not important. The VC diameter in both speakers happens to be the same -- and there's a lot more that goes into dissipating heat than just the size of the VC anyway. So, it seems to me that you're GUESSING that your speakers are more immune to power compression and...well...you haven't provided one iota of evidence in support of that assertion.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> Of course. But I gave you numbers based on modern highly compressed music at -10db average. That's around 1/10th the wattage output of the RMS rating of the amp with the way I set it.


But "averages" on such a broad scale are meaningless. For example, if you added a 3 minute passage of silence at the end, it would bring down the average considerably. But, realistically, the power delivered to the speaker during the loud parts would still be the same. Speakers don't blow at the END of a listening session. They blow during the loud parts!

So if you have, say, a 1 minute portion of the song that's much louder than the rest of it, then the power content could be CONSIDERABLY greater than your mean power. But you're relying so heavily on the mean and ignoring transients, even though I've asked you about transients five million times.



> As I said, you could look at it either way (as one or two coils) but the math and the thermal handling will come out the same. So, I don't see the point in wasting time on semantics.


Exactly my point. You're basing the idea that your speakers reject power compression more than the JBL speakers on the notion that your speaker has more voice coils than the JBL. But, as I've demonstrated, that's a red herring. The "dual voice coil" arrangement is pretty much equivalent to having a second set of taps off a transformer. The amount of metal is identical; the space they share is identical. From a thermal standpoint, there's no difference. So you're basing your assumption on junk.



> I'm sure they don't but the 1200-watt RMS rating is set by Cadence as a full-duty tone at it's RMS. For what length of time, I'm not sure.


I was talking about the sub power rating. You don't know how they arrive at it. They say "600wrms", right? Do they explain how they arrived at that number? If they're like most car audio manufacturers, that means listening to music with a 600w amp.



> Ask RE-Audio. They would know. I'm assuming they mean it.


"Hey, are your ratings genuine?"
"Nope, we lie."

Yeah, I'm sure a manufacturer would say something like that. The question is HOW they arrived at the rating. In other words, what test did they perform? Is it a continuous 600w 100% duty cycle signal for 2 hours? Or is it a "600w" -6dB crest factor signal for 5 minutes?



> 600-watts RMS, 1200-watts peak, per sub. So, yes, I do think that's what they are intending to say. Again, for what length of time? I couldn't know but that is the rating. My settings are for a full-duty tone to reach 1200-watts, which would be a "peak" output.





> I'm just going on the ratings. Other people posted videos on the web showing some outrageous excursions and outputs from these subs on a level I'm not even attempting. These subs in the right setups can get upwards of the 140'sdb of SPL. My PEAK is for only 119db which will only be reached if I crank my volume as high I dare (75% of max) and a CD plays some bass notes briefly at 0db peak. My settings are very conservative. I'm not too worried about power compression.


Irrelevant. We're talking about power compression here, not short term mechanical limits or even thermal power handling.



> No, that's not what I said. I said my music average wattage output will be 1/10th the RMS capability of the sub amp and subwoofer.


Uh...yeah, and therefore the RMS capability of the subwoofer would be reached with a 12kW amp (since yours is 1200W) listening to the same music. At least, that's according to your theory that you're only operating within 1/10th of the speaker's limits. So yes, that is what you're saying.


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## tspence73 (Oct 14, 2008)

MarkZ said:


> I have to say, I'm baffled as to why you think your speakers are more immune to power compression than these speakers are.


I'm saying that coil size for coil size my subs would have to be somewhere in the ballpark of the thermal compression of that JBL speaker. And if my subs are close, then I'm not going to have to worry about thermal compression effects much at all. 



> Yeah, yeah, I know, it has more taps on the voice coil. But I think (I hope) you understand now why that's not important. The VC diameter in both speakers happens to be the same -- and there's a lot more that goes into dissipating heat than just the size of the VC anyway.


These RE SE subs have a fairly robust design for dissapating heat from the voice coil and a nice magnet section that acts much like a heat sink.



> So, it seems to me that you're GUESSING that your speakers are more immune to power compression and...well...you haven't provided one iota of evidence in support of that assertion.


To a degree, yes, I'm guessing because I haven't gone over the math to calculate what level of compression my subs are getting. I don't think they will be too different from that JBL driver and if that's the case the compression effects should be minimal.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> I'm saying that coil size for coil size my subs would have to be somewhere in the ballpark of the thermal compression of that JBL speaker. And if my subs are close, then I'm not going to have to worry about thermal compression effects much at all.


Ok. But I think it's a mistake to make the sorts of assumptions that you're making. Specifically, 
(a) that your subs are similar to (or better than) those JBL's in terms of keeping temperatures low, simply because the coils are similar. There are lots of factors that influence temperature. Maybe the REs are better? Maybe they're worse? I don't know and it doesn't seem that you do either.
(b) that power compression and thermal power handling are as tightly coupled as you seem to think they are. Some speakers can simply allow their VCs to get hotter before failing. This has a lot to do with the properties of the former, the vc material winding coating, and the glues, etc. So maybe your RE subs can handle higher temps? That doesn't necessarily mean that they'll be more immune to power compression.



> These RE SE subs have a fairly robust design for dissapating heat from the voice coil and a nice magnet section that acts much like a heat sink.


Eh, the magnets aren't doing a lot of sinking. You can add a magnet with a 10 foot radius and it's not really going to do anything. What's more important is the metal that's proximal to the VC former. The top plate. The size of the gap. The dependence on forced air convection. The geometry of the VC (ie. its packing fraction and surface area). Its thermal coupling basically to the pole piece. The list goes on. Your subs might be really good in that regard. Or maybe the JBLs are actually better. I don't know.



> To a degree, yes, I'm guessing because I haven't gone over the math to calculate what level of compression my subs are getting. I don't think they will be too different from that JBL driver and if that's the case the compression effects should be minimal.


What math? You don't have data to do math on.


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## tspence73 (Oct 14, 2008)

MarkZ said:


> Uh...yeah, and therefore the RMS capability of the subwoofer would be reached with a 12kW amp (since yours is 1200W) listening to the same music. At least, that's according to your theory that you're only operating within 1/10th of the speaker's limits. So yes, that is what you're saying.


Again, let's go through it. 

The amp is set to output 1200-watts at 0db peaks on CDs.

The average output of typical modern music is -10db.

So, the average wattage output on my settings will be around 100-120 watts "IF" I turn up the volume on my headunit to 75% of max, (or what I consider my "max" volume to be when I'm listening).


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## tspence73 (Oct 14, 2008)

MarkZ said:


> What math? You don't have data to do math on.


I could contact RE Audio. Maybe they might have more insight on this topic. I'm just a bit tired of all this. I want to get back to tweaking my system and listening. The kick panels are being custom made for me and it's been days and days. They're almost done. Then the door panel mod will be done for the midbass. The kickpanels are coming along real well.


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## MarkZ (Dec 5, 2005)

tspence73 said:


> Again, let's go through it.
> 
> The amp is set to output 1200-watts at 0db peaks on CDs.
> 
> ...


Right. And you're saying that "average wattage output" is meaningful. But it really isn't as long as you're ignoring variations in level over the course of a song. 

To demonstrate this, I've extrapolated your assumption that you're only operating the subs at 1/10th of their capabilities. If your average power was 10 times greater, then you'd be operating the subs at 100% of their capabilities (according to you). That would mean the identical setup and settings you have now, but with a 12kW amp. So, according to your theory, you won't begin to exceed the thermal properties of a 600w sub until you get a 12kW amp.


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## tspence73 (Oct 14, 2008)

MarkZ said:


> Right. And you're saying that "average wattage output" is meaningful. But it really isn't as long as you're ignoring variations in level over the course of a song.
> 
> To demonstrate this, I've extrapolated your assumption that you're only operating the subs at 1/10th of their capabilities. If your average power was 10 times greater, then you'd be operating the subs at 100% of their capabilities (according to you). That would mean the identical setup and settings you have now, but with a 12kW amp. So, according to your theory, you won't begin to exceed the thermal properties of a 600w sub until you get a 12kW amp.


That's a real stretch and not what what I meant at all. Anyone following the thread and thinking rationally would know that. I meant that to really cook up the sub, you would have to get that average up and clip the amp by a decent amount. Maybe by 20% or more, which most people actually do to their sub stages. These subs have been known to get 130dbs+ with sealed enclosures and similar amp power, yet with my setting I'm not getting anywhere near that output.


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## Jimi77 (Jul 4, 2005)

MarkZ said:


> Ok. But I think it's a mistake to make the sorts of assumptions that you're making. Specifically,
> (a) that your subs are similar to (or better than) those JBL's in terms of keeping temperatures low, simply because the coils are similar. There are lots of factors that influence temperature. Maybe the REs are better? Maybe they're worse? I don't know and it doesn't seem that you do either.
> (b) that power compression and thermal power handling are as tightly coupled as you seem to think they are. Some speakers can simply allow their VCs to get hotter before failing. This has a lot to do with the properties of the former, the vc material winding coating, and the glues, etc. So maybe your RE subs can handle higher temps? That doesn't necessarily mean that they'll be more immune to power compression.
> 
> ...


LOL - Mark you're going way above tspence's head. I'm going to guess he came up with that crap about the magnet acting as a heat sink from somebody's marketing material - he's been known to be duped by the marketing gurus. T

The magnet structure actually traps heat (air). If it truly acted like a heat sink, then heat related failures would be non-existent.


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## AWC (Mar 31, 2008)

tspence73 said:


> That's a real stretch and not what what I meant at all. Anyone following the thread and thinking rationally would know that. I meant that to really cook up the sub, you would have to get that average up and clip the amp by a decent amount. Maybe by 20% or more, which most people actually do to their sub stages. These subs have been known to get 130dbs+ with sealed enclosures and similar amp power, yet with my setting I'm not getting anywhere near that output.


substages?:shame: Don't give yourself away my little fishy. 

To clarify one point mentioned early in this post as highlighted by dark red lettering...ahem....anyone thinking rationally would not be following this thread, therefore, don't assume anything. Anybody listening to your swill is fairly off their rocker and should be rebuked before their peers. Luck be with you. How are you holding up to this weather, Bob? Its worse on your side of the mountains, ehh?


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## MarkZ (Dec 5, 2005)

tspence73 said:


> That's a real stretch and not what what I meant at all.


Stretch?? It's the logical conclusion of your assertion that you're operating the sub at 10% of its capacity! Therefore, to operate the sub at 100% of its capacity, you'd have to deliver 10 times the power! We call that multiplication.


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## MarkZ (Dec 5, 2005)

Jimi77 said:


> LOL - Mark you're going way above tspence's head. I'm going to guess he came up with that crap about the magnet acting as a heat sink from somebody's marketing material - he's been known to be duped by the marketing gurus. T
> 
> The magnet structure actually traps heat (air). If it truly acted like a heat sink, then heat related failures would be non-existent.


Well, actually, magnets do act as a sink within the immediate vicinity of the coil. But it's ridiculous to think that the oversized magnet on those RE subs is doing something that the (already large) magnet on the JBL's isn't.


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## Knobby Digital (Aug 17, 2008)

So physics evolve to suit your system, must be nice. Please tell us that at least your **** stinks.


Internet reps who say whatever it takes to shut a fool ass customer up are obviously smarter than a squad of people who're trying to educate you in their own way for your own benefit.

I've suggested in the past that Spense doesn't deserve detailed responses containing anything other than perspective, since anything that doesn't support his theories is either false or disregarded.



Why don't you email RE, link them to this thread, and get their take on it? I think that's the only way we'll get some closure on this.


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## MarkZ (Dec 5, 2005)

icehole said:


> So physics evolve to suit your system, must be nice. Please tell us that at least your **** stinks.
> 
> 
> Internet reps who say whatever it takes to shut a fool ass customer up are obviously smarter than a squad of people who're trying to educate you in their own way for your own benefit.
> ...


They'll never read it. Why should they?

If he wants to get an understanding of the amount of power compression that he's dealing with, there's only one way to figure it out: measure it.


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## Knobby Digital (Aug 17, 2008)

MarkZ said:


> They'll never read it. Why should they?


Because they'll have a great laugh in the office? I can almost guarantee that they'll be far too intrigued to stop at the first page. This is why I refer to li'l homie as (su)Spense.


It is however likely that he won't get a response. But Spense isn't one to take 'no' for an answer.


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## Knobby Digital (Aug 17, 2008)

I'm sure that at least one rep from RE lurks this forum looking for posts regarding their product and has been following this.

That person has just shat down both legs.


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## aztec1 (Jun 13, 2008)

tspence73 said:


> There is a whole section of additional mass acting like a heatsink for the coils PLUS moving air that is channeled specifically for cooling the coils. The subwoofers (and yes, that's more than one) is not likely to get as hot as a light bulb given the same 100-watts. It's not much different than computer processors and cooling them. Modern processors on computers and cooling them is a great example. If I stick a bunch of heat conducting mass on a PC processor and air cool it, it stays far cooler than a processor without any cooling. People here who build their own PCs know that modern processors must have cooling and the difference in temp with cooling is dramatic.


Thank you, but I know how a speaker motor works and how it's constructed. I'm also well aware of thermodynamics. Keep this in mind: transferred and radiated heat are two separate things, heat caused by current flow is quite another...even in the exact same piece of metal. 

And please, there's no need to be rude. I was just trying to clarify something.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> Laugh all you want.


Another Tspence thread raped into YSHSF? I'll take you up on that offer. 

:laugh4:  :laugh:

But most of all

:dunce:	:dunce:	:dunce:	:dunce:	:dunce:	:dunce:


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## tspence73 (Oct 14, 2008)

aztec1 said:


> Thank you, but I know how a speaker motor works and how it's constructed. I'm also well aware of thermodynamics. Keep this in mind: transferred and radiated heat are two separate things, heat caused by current flow is quite another...even in the exact same piece of metal.
> 
> And please, there's no need to be rude. I was just trying to clarify something.


I wasn't trying to be rude. I was just explaining my side. Don't take it that way. This site should be about dialog and discussion, sometimes debate, but I never intend to insult anyone for real. Take things with a grain of salt with me. This site is half entertainment, half technical audio discussion. If it was any other way, it would be a crappy place to post. Why do you think so many people read my threads? Coincidence? No. I have the most entertaining threads on any car audio bulletin board. I should get some kind of kickback for all the extra traffic I bring here to view the ads at the top of every page on the site. Oh, and BTW, I intend to use Second Skin as my company of choice for my February phase 2 acoustics project. So, there is a direct plug right there.  Second skin is tspence approved. :thumbsup:


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## tspence73 (Oct 14, 2008)

Jimi77 said:


> LOL - Mark you're going way above tspence's head. I'm going to guess he came up with that crap about the magnet acting as a heat sink from somebody's marketing material - he's been known to be duped by the marketing gurus. T
> 
> The magnet structure actually traps heat (air). If it truly acted like a heat sink, then heat related failures would be non-existent.


Actually, there is a pole vent through the magnet smarty pants. No, no marketing claims swallowed here, just trying my best. These subs are really amazing. Too bad for you.


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## tspence73 (Oct 14, 2008)

MarkZ said:


> Well, actually, magnets do act as a sink within the immediate vicinity of the coil. But it's ridiculous to think that the oversized magnet on those RE subs is doing something that the (already large) magnet on the JBL's isn't.


Does the JBL have a pole vent through the middle of the magnet? I bet not. Just an assumption but I bet not. And that vent carries heat out with the air flow of the driver. It's a significant difference in temp due to that one design feature. Air certainly does wonders when it comes to cooling, now don't it?


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## MarkZ (Dec 5, 2005)

tspence73 said:


> Does the JBL have a pole vent through the middle of the magnet? I bet not. Just an assumption but I bet not. And that vent carries heat out with the air flow of the driver. It's a significant difference in temp due to that one design feature. Air certainly does wonders when it comes to cooling, now don't it?


That's one way of improving cooling, along with literally DOZENS of other strategies. I don't know if that particular speaker does it or not. A quick google search reveals that the 2206 may have that feature (and other differences as well), and it happens to have a very similar power compression measurement. So, no, the presence or absence of that feature is not enough to eliminate power compression.

The various strategies that can be used to reduce VC temperature are mentioned in this pdf I have...


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> Second skin is tspence approved. :thumbsup:


"It was reported today that Second Skin mysteriously went out of business following an online endorsement..." :stunned:



tspence73 said:


> I should get some kind of kickback for all the extra traffic I bring here to view the ads at the top of every page on the site.


Yes Ant should mail you a check for all the .000010 cent clickthroughs he got 
BTW they get paid by # of UNIQUE users, not the same people refreshing a thread over and over again.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> I should get some kind of kickback for all the extra traffic I bring here to view the ads at the top of every page on the site.


Sure, but no more than the average circus freak.


Go look up the mean bearded lady's salary and tell DIYMA what they owe you.


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> Does the JBL have a pole vent through the middle of the magnet? I bet not. Just an assumption but I bet not.


Do you think that's some incredibly unique feature?


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> Does the JBL have a pole vent through the middle of the magnet? I bet not. Just an assumption but I bet not. And that vent carries heat out with the air flow of the driver. It's a significant difference in temp due to that one design feature. Air certainly does wonders when it comes to cooling, now don't it?


Even many midbass drivers have pole vents. It seems to me that given JBL's concern about power compression, that the driver would include a pole vent. It's pretty rare for a sub to lack a pole vent; I can only think of two. 

Hey are your Infinities also immune to the effects of power compression too or just your subs?


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## tspence73 (Oct 14, 2008)

shadowfactory said:


> "It was reported today that Second Skin mysteriously went out of business following an online endorsement..." :stunned:
> 
> 
> 
> ...


I suppose the word "joke" isn't in your vocabulary. You can't honestly think I was making serious statements. Jeez, you people need to seriously, lighten up, and drink some pepto. This is Christmas time. :santa2: Have some fun.


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## aztec1 (Jun 13, 2008)

tspence73 said:


> I wasn't trying to be rude. I was just explaining my side. Don't take it that way. This site should be about dialog and discussion, sometimes debate, but I never intend to insult anyone for real. Take things with a grain of salt with me. This site is half entertainment, half technical audio discussion. If it was any other way, it would be a crappy place to post. Why do you think so many people read my threads? Coincidence? No. I have the most entertaining threads on any car audio bulletin board. I should get some kind of kickback for all the extra traffic I bring here to view the ads at the top of every page on the site. Oh, and BTW, I intend to use Second Skin as my company of choice for my February phase 2 acoustics project. So, there is a direct plug right there.  Second skin is tspence approved. :thumbsup:


Understood, although some might see nebulous information as something other than entertaining, which accounts for at least some of the traffic.


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## shadowfactory (Oct 20, 2008)

tspence73 said:


> I suppose the word "joke" isn't in your vocabulary. You can't honestly think I was making serious statements. Jeez, you people need to seriously, lighten up, and drink some pepto. This is Christmas time. :santa2: Have some fun.


Nice way to avoid all the serious replies that contain actual information you mysteriously refuse to acknowledge and accept. :inquisitive:


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## Knobby Digital (Aug 17, 2008)

tspence73 said:


> Jeez, you people need to seriously, lighten up, and drink some pepto.


The only person who needs to drink anything is the fool who comes to the bukkake fest of information with an umbrella.


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## Jimi77 (Jul 4, 2005)

tspence73 said:


> Actually, there is a pole vent through the magnet smarty pants. No, no marketing claims swallowed here, just trying my best. These subs are really amazing. Too bad for you.



No ****.... you mean like on almost every other subwoofer in production. :thumbsup:


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