# High voltage 12v amplifiers are better than high current 12v amplifiers



## ChrisB (Jul 3, 2008)

In another thread that got totally out of hand, it was touted by some that high voltage amplifiers were better than high current amplifiers. They started talking about this 12v amplifier that had 120 volt DC rails inside of it stating that it can make all kinds of power all day long with minimal current draw, thus violating the properties of ohm's law.

Myth or fact, high voltage 12 volt amplifiers are better than high current amplifiers?

Some links for your viewing pleasure:
http://www.diymobileaudio.com/forum/16347-post1.html

http://www.diymobileaudio.com/forum/general-car-audio-discussion-no-question-dumb/89491-high-voltage-high-current.html

http://www.diymobileaudio.com/forum/200906-post21.html

Discuss!


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## Cablguy184 (Oct 7, 2010)

Question here ...

Are we talking about Sound Quality music reproduction systems ... or are we talking about Competition High SPL vehicles with a 10 second burp or a 30 second loud streetbeat type system ... 
If you are talking about High SPL levels with no Sound Quality or just to be (rap loud) ... then this discussion is over already for me ...


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## ChrisB (Jul 3, 2008)

Cablguy184 said:


> Question here ...
> 
> Are we talking about Sound Quality music reproduction systems ... or are we talking about Competition High SPL vehicles with a 10 second burp or a 30 second loud streetbeat type system ...
> If you are talking about High SPL levels with no Sound Quality or just to be (rap loud) ... then this discussion is over already for me ...


All of the above, state your case and your reason for supporting one designe over another.

IMHO, *BOTH* have their places in car audio depending on intended use. High voltage amplifiers will work great with high impedance drivers, such as 8 ohm pro audio speakers that are commonly used by the DIY crowd in automobiles. Another common way to implement 8 ohm drivers is to bridge 4 channel amplifiers to a pair of 8 ohm drivers. You can take a relatively inexpensive 60x4 amplifier, bridge it to a pair of 8 ohm drivers, and it will be working no harder bridged at 8 ohms than it would have working to power 4 channels at 4 ohms. 

High current amplifiers are generally the better choice for subwoofer use where 2 and 1 ohm loads are common. In my particular case, my options are either 2 or 8 ohms depending on how I want to run my single subwoofer. You know how expensive 750+ watts RMS at 8 ohms is compared to finding it in a 2 ohm variant? Also, my particular situation is not ideal to run one coil while connecting an adjustable gain pot perform some resistive Q tuning tricks.


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## Cablguy184 (Oct 7, 2010)

If they both have their places in car audio depending on intended use ... The how can you determine the better amplifier ???

Class a/b more towards sound quality and class d more advertised for higher spl numbers and louder bass ...

I'm not sure what you are starting here ...


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## ChrisB (Jul 3, 2008)

Cablguy184 said:


> If they both have their places in car audio depending on intended use ... The how can you determine the better amplifier ???


Exactly, how do you? Feel free to discuss!



Cablguy184 said:


> Class a/b more towards sound quality and class d more advertised for higher spl numbers and louder bass ...


Well, that is just an over-generalized, broad statement right there. I'm quite sure that Steven Mantz from Zed Audio would disagree with you on this one.

Didn't Mark Eldridge win a bunch of SQ competitions with JL Audio HD amplifiers? Are you sure full-range Class D is just for SPL?



Cablguy184 said:


> I'm not sure what you are starting here ...


A discussion!


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## envisionelec (Dec 14, 2005)

Nope.


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## Cablguy184 (Oct 7, 2010)

ChrisB said:


> Well, that is just an over-generalized, broad statement right there. I'm quite sure that Steven Mantz from Zed Audio would disagree with you on this one.
> 
> Didn't Mark Eldridge win a bunch of SQ competitions with JL Audio HD amplifiers? Are you sure full-range Class D is just for SPL?


I'm not going to argue with you Chris ... 
You know I run a 502hv at 8 ohms on my system with 4 10s Isoberic ... pulling a consistant 136 db at 28 htz every time I go thru a meter ...

This is what I plan to do ... I will be at USACI and MECA finals ... Why don't you meet me there and lets count the Sound Quality vehicles and see what they are running for amplifiers ... front, rear, center, and sub stages ... 
Tally up the percentages of amplifiers and then we will have this issue solved ... Majority rules ... 

What say you ???


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## Cablguy184 (Oct 7, 2010)

As a matter of fact, why don't you bring your SQ ride to the shows so we can compare notes ... interested ???


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## ChrisB (Jul 3, 2008)

Cablguy184 said:


> As a matter of fact, why don't you bring your SQ ride to the shows so we can compare notes ... interested ???


Sorry, I don't have a SQ vehicle at the moment.



Cablguy184 said:


> This is what I plan to do ... I will be at USACI and MECA finals ... Why don't you meet me there and lets count the Sound Quality vehicles and see what they are running for amplifiers ... front, rear, center, and sub stages ...
> Tally up the percentages of amplifiers and then we will have this issue solved ... Majority rules ...
> 
> What say you ???


You're going to leave out IASCA too? I'm sure we can look up what all the winners are running on the various web sites. Let's take a tally!


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## Cablguy184 (Oct 7, 2010)

ChrisB said:


> Sorry, I don't have a SQ vehicle at the moment.
> 
> 
> 
> You're going to leave out IASCA too? I'm sure we can look up what all the winners are running on the various web sites. Let's take a tally!


I'm a active competitor for USACI and Will be active MECA next year (going to finals to see the competition) ... I do not compete IASCA ... no reason for me to be there ... 

So you do not compete and you do not have a sound quality vehicle to back up your actions ...
Just like a person that does not vote ... They should not complain or even talk about politics ... absolutely worthless ...


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## ChrisB (Jul 3, 2008)

Cablguy184 said:


> I'm a active competitor for USACI and Will be active MECA next year (going to finals to see the competition) ... I do not compete IASCA ... no reason for me to be there ...
> 
> So you do not compete and you do not have a sound quality vehicle to back up your actions ...
> Just like a person that does not vote ... They should not complain or even talk about politics ... absolutely worthless ...


As far as I am aware, USACi is the only sound competition organization in Louisiana. I refuse to compete in an organization that used to allow individuals place the microphone ANYWHERE for their "dash legal" score. Yes I witnessed that at a local event and at one time I had photos to back it up prior to a hard drive crash! When I asked the judge about the microphone placement, he said "It don't matter." Want to guess who was also listening to the SQ cars?

EDIT: Oh yeah, I forgot to mention the reason I don't compete in SQ, aside from my total disgust for USACi. I build my car audio setups to put a smile on my face while driving, not to impress some judge in a situation that will never happen. In other words, aside from tuning the car, you'll never catch me sitting there performing critical listening for any extended period of time because that is what I have home audio for! Also, I am friends with a former IASCA competitor and I know what those competition cars are supposed to sound like and that competition sound is far from what I want out of a daily driver setup. Call me selfish, stingy, or whatever else you want to, but there is only one person my setup has to impress, and that is ME!

Answer this question for me, just how many people compete against you in your SQ class at each USACi event?


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## XtremeRevolution (Dec 3, 2010)

Cablguy184 said:


> If they both have their places in car audio depending on intended use ... The how can you determine the better amplifier ???
> 
> Class a/b more towards sound quality and class d more advertised for higher spl numbers and louder bass ...
> 
> I'm not sure what you are starting here ...


Neither of the classes are geared toward either. It just so happens that some have been more popular than other. 

Class D technologies of the past decade have been unsuitable for higher frequency response, which is why they have been left to subwoofer duty. Times have changed and it needs to be acknowledged that Class D and Class D variants have been released in the last 1-2 years that not only compete with, but outperform Class AB amplifiers in sound quality, some of which even rival tube amplifiers. This is not the year 2001 anymore. In fact, there exists quite a large variety of class D stereo amplifiers for car use, and many home theater amplifier manufacturers have adopted Class D architecture variants for their $2000+ flagship receivers and amplifiers. 

It is no longer possible to make blanket statements about amplifier architectures.


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## MTU_Husky (Jun 8, 2011)

XtremeRevolution said:


> Neither of the classes are geared toward either. It just so happens that some have been more popular than other.
> 
> Class D technologies of the past decade have been unsuitable for higher frequency response, which is why they have been left to subwoofer duty. Times have changed and it needs to be acknowledged that Class D and Class D variants have been released in the last 1-2 years that not only compete with, but outperform Class AB amplifiers in sound quality, some of which even rival tube amplifiers. This is not the year 2001 anymore. In fact, there exists quite a large variety of class D stereo amplifiers for car use, and many home theater amplifier manufacturers have adopted Class D architecture variants for their $2000+ flagship receivers and amplifiers.
> 
> It is no longer possible to make blanket statements about amplifier architectures.


Sorry, but tube amps are not high SQ, tubes distort and add noise to the signal, while some people may prefer the warm sound that generates they are not being true to the signal. The main advantage tubes have is they clip a lot softer than solid state and this can be used to great effect in guitar amps.


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## envisionelec (Dec 14, 2005)

MTU_Husky said:


> Sorry, but tube amps are not high SQ, tubes distort and add noise to the signal, while some people may prefer the warm sound that generates they are not being true to the signal. The main advantage tubes have is they clip a lot softer than solid state and this can be used to great effect in guitar amps.


Not necessarily. A tube amplifier can have a flat frequency response just as a solid state amplifier. It requires a well designed output transformer.


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## wizner (Feb 22, 2011)

MTU_Husky said:


> Sorry, but tube amps are not high SQ, tubes distort and add noise to the signal, while some people may prefer the warm sound that generates they are not being true to the signal. The main advantage tubes have is they clip a lot softer than solid state and this can be used to great effect in guitar amps.


um, please be careful bashing tube amps. there are plenty of sound technicians and engineers on this forum that will give u a plethora of concrete, tested evidence that says other wise. i recently was lucky enough to hear a system powered by twin Audio Research Reference 610t's and you wouldnt believe what a life event that is.

ive been into formula 1 ever since i can remember and read so much technical information about it its ridiculous, i even have a book i paid a ton of money for thats mostly charts, graphs, flow data, etc. and there is no way i can tell anyone how it feels to pull over 5 g's in a corner milimeters away from marbles that could end my life ya know.


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## Luke352 (Jul 24, 2006)

MTU_Husky said:


> Sorry, but tube amps are not high SQ, tubes distort and add noise to the signal, while some people may prefer the warm sound that generates they are not being true to the signal. The main advantage tubes have is they clip a lot softer than solid state and this can be used to great effect in guitar amps.


50w Tube amp 0.005% distortion with perfectly flat response. http://burwenaudio.com/Krohn-Hite_UF-101.pdf

This is the designer. burwenaudio.com HOME


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## XtremeRevolution (Dec 3, 2010)

I think its safe to say the point has been made. Class D is not the same as it was a few years ago. People need to realize that its a different playing field, where Class D stereo amps might start kicking serious ass on the SQ side once more people start using them.


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## ChrisB (Jul 3, 2008)

XtremeRevolution said:


> I think its safe to say the point has been made. Class D is not the same as it was a few years ago. People need to realize that its a different playing field, where Class D stereo amps might start kicking serious ass on the SQ side once more people start using them.


I said it in another thread, and I'll repeat it here... I am tired of devoting 1/3 of a trunk to class AB amplifiers along with beefing up an electrical system for "normal" listening levels. The next time I purchase new amplifiers, I am probably going to go with ALL full range class D. Furthermore, they will probably have a RIPS system.


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## narvarr (Jan 20, 2009)

ChrisB said:


> In another thread that got totally out of hand, it was touted by some that high voltage amplifiers were better than high current amplifiers. They started talking about this 12v amplifier that had 120 volt DC rails inside of it stating that it can make all kinds of power all day long with minimal current draw, thus violating the properties of ohm's law.


It does not violate Ohm's law it actually supports it. You can get the same wattage with high voltage or high current. Which one is better depends on application. High voltage is mostly used for higher frequencies because of how the current reacts to the voice coils inductance. A low inductance speaker paired to a high current amp basically cancels out any advantage of the low inductance of the voice coil. A high voltage amp would do a better job. Read this post by Andy Wehmeyer for a better explanation on how back EMF. 
http://www.diymobileaudio.com/forum/449977-post34.html


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## ChrisB (Jul 3, 2008)

narvarr said:


> It does not violate Ohm's law it actually supports it. You can get the same wattage with high voltage or high current.


Umm, one of the fanbois told me his high voltage 12v amplifier could produce 1,500 watts RMS at 8 ohms, all day long... *On a 60 amp fuse.* THAT violates Ohm's Law! 

Sorry for not explaining that better in the original post. 



narvarr said:


> Which one is better depends on application. High voltage is mostly used for higher frequencies because of how the current reacts to the voice coils inductance. A low inductance speaker paired to a high current amp basically cancels out any advantage of the low inductance of the voice coil. A high voltage amp would do a better job. Read this post by Andy Wehmeyer for a better explanation on how back EMF.
> http://www.diymobileaudio.com/forum/449977-post34.html


Thank you!


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## narvarr (Jan 20, 2009)

ChrisB said:


> Umm, one of the fanbois told me his high voltage 12v amplifier could produce 1,500 watts RMS at 8 ohms, all day long... *On a 60 amp fuse.* THAT violates Ohm's Law!
> 
> Sorry for not explaining that better in the original post.
> 
> ...


25 volts at 60 amps gives you 1,500 watts...may or may not be CLEAN wattage though. Most high voltage amps put out the same power at 4 and 8 ohms but don't do well with low impedance loads. That is one of the things LP amps are well known for, putting out the same power with either 4 or 8 ohm loads.


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## ChrisB (Jul 3, 2008)

narvarr said:


> 25 volts at 60 amps gives you 1,500 watts...may or may not be CLEAN wattage though. Most high voltage amps put out the same power at 4 and 8 ohms but don't do well with low impedance loads. That is one of the things LP amps are well known for, putting out the same power with either 4 or 8 ohm loads.


Yes, but we are talking from a 12 volt electrical system and something with typical class ab efficiency. Even with 100% efficiency and being nice by assuming the system can make 14.4 volts without drop, one will only get 864 watts RMS. Where do the other 636 come from?

EDIT: Even in a "high voltage" amplifier design, energy (or power in this case) can not be created or destroyed. Hence you have my stab at the violation of the laws of physics.


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## narvarr (Jan 20, 2009)

ChrisB said:


> Yes, but we are talking from a 12 volt electrical system and something with typical class ab efficiency. Even with 100% efficiency and being nice by assuming the system can make 14.4 volts without drop, one will only get 864 watts RMS. Where do the other 636 come from?
> 
> EDIT: Even in a "high voltage" amplifier design, energy (or power in this case) can not be created or destroyed. Hence you have my stab at the violation of the laws of physics.


To be honest, I would say that he may be putting out only 600 at best, but, not knowing what amp he's using, I'm not going to speculate. Amp design is the key factor. I talked to Stephon (Mr. Zed Audio) and he told me that the levithan amp only draws 15amps with all channels driven at rated powet in stereo at 4 ohms using pink noise. That's 150 watts by 6...that's still unheard of even for class D. But, as was said earlier, amps have come a long way.


Sent from my X10i using Tapatalk


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## MTU_Husky (Jun 8, 2011)

narvarr said:


> To be honest, I would say that he may be putting out only 600 at best, but, not knowing what amp he's using, I'm not going to speculate. Amp design is the key factor. I talked to Stephon (Mr. Zed Audio) and he told me that the levithan amp only draws 15amps with all channels driven at rated powet in stereo at 4 ohms using pink noise. That's 150 watts by 6...that's still unheard of even for class D. But, as was said earlier, amps have come a long way.
> 
> 
> Sent from my X10i using Tapatalk


That is an absolute impossibility, the laws of physics, namely Ohm's Law proves this. To produce 900 watts on a 14.4v system you have to draw 62.5 amps at 100% efficiency, with 80% efficiency you need to draw 78.125 amps, this is an absolute, YOU CANNOT VIOLATE THIS!! This is especially true with pink noise since it is a constant signal. On a peak the amp could deliver more power because of the storage caps inside of the amp however these will be draing after a couple of transients, on a long pink noise tone this will not really be storing any power and you will be drawing the full current needed to drive the amp.


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## narvarr (Jan 20, 2009)

I think we are looking at this from the wrong angle. Higher voltage means less current. Supply voltage to the amp may be 14.4v DC but what is the amps internal voltage?

Sent from my X10i using Tapatalk


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## ChrisB (Jul 3, 2008)

narvarr said:


> I think we are looking at this from the wrong angle. Higher voltage means less current. Supply voltage to the amp may be 14.4v DC but what is the amps internal voltage?
> 
> Sent from my X10i using Tapatalk


It doesn't matter what the rail voltage of the amplifier is because it still requires supply voltage and supply current to make power. Remember what I wrote earlier, energy can neither be created nor destroyed.

As for what Mr. Mantz stated, he may have been referring to average current draw on musical signal. I tend to recall a test of the Leviathan where the average current draw while reproducing music was quite low. It was real close to the 15 amps that you are touting, but as fate would have it, I can't find the test.

Now, let's compare this to an old school, class ab counterpart that will have near single digit efficiency while reproducing music at normal levels. I owned both high voltage and high current products from back in the day and remember watching the headlights dim to the beat of the music at low volume levels when driving home at night. Heck, at one time, I had a setup that could dang near black out the headlights when playing "Posse on Broadway" by Sir Mix-a-Lot.:laugh: I don't miss those days of having 3 batteries prior to switching to a RV isolator.


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## narvarr (Jan 20, 2009)

I see your point. I'm not by any means an expert at amp design, but I'm just keeping an open mind about the situation. Zed's amps seemed to have crossed a new theshold in efficiency for class D for sure.

Sent from my X10i using Tapatalk


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## envisionelec (Dec 14, 2005)

ChrisB said:


> It doesn't matter what the rail voltage of the amplifier is because it still requires supply voltage and supply current to make power. Remember what I wrote earlier, energy can neither be created nor destroyed.
> 
> As for what Mr. Mantz stated, he may have been referring to average current draw on musical signal. I tend to recall a test of the Leviathan where the average current draw while reproducing music was quite low. It was real close to the 15 amps that you are touting, but as fate would have it, I can't find the test.
> 
> Now, let's compare this to an old school, class ab counterpart that will have near single digit efficiency while reproducing music at normal levels. I owned both high voltage and high current products from back in the day and remember watching the headlights dim to the beat of the music at low volume levels when driving home at night. Heck, at one time, I had a setup that could dang near black out the headlights when playing "Posse on Broadway" by Sir Mix-a-Lot.:laugh: I don't miss those days of having 3 batteries prior to switching to a RV isolator.


PASMAG | PERFORMANCE AUTO AND SOUND - ZED Audio Leviathan

audio gear reviews - Amplifier Review - ZED Audio Leviathan

I find the latter review more thorough. Stephen knows how amps get done. He is _my_ idol.


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## asota (Feb 7, 2011)

Fuses in amps are really only for short circuit (fire) prevention the amps have electronic protection built in for, over temp, low impedance, ect. Many high output amps including some from LP require slow-blow fuses. A amp playing music will rarely reach top rated output for any length of time usually just momentary peaks. A slow blow-fuse is designed to handle peaks in current handling up to 10x there rating for several seconds. Most amps will shut-down on over temp before they come close to clearing a fuse after long play with full power peaks.


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## Luke352 (Jul 24, 2006)

ChrisB said:


> It doesn't matter what the rail voltage of the amplifier is because it still requires supply voltage and supply current to make power. Remember what I wrote earlier, energy can neither be created nor destroyed.
> 
> Agreed the LP fanboi's seem to have this strange notion that because there amps have a high rail voltage that it gives them the magical ability to have Class D equaling efficiency completely forgetting that to get that high rail voltage with sufficient current off 12v takes lots of current
> 
> ...



Yep I just went through the amp reviews on Audio Gear and at 1/3 power the Class D's worst efficiency was 68% and the best 83% most were in the mid to high 70's as for the a/b's the worst was 25% and the best was 38% so from that we could claim playing music Class D's for similar output power will use 1/2 to 1/3 of the power since playing music just short of clipping will generally draw about 1/3 the current of a sine wave which is why they measure at 1/3.


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## ChrisB (Jul 3, 2008)

asota said:


> Fuses in amps are really only for short circuit (fire) prevention the amps have electronic protection built in for, over temp, low impedance, ect. Many high output amps including some from LP require slow-blow fuses. A amp playing music will rarely reach top rated output for any length of time usually just momentary peaks. A slow blow-fuse is designed to handle peaks in current handling up to 10x there rating for several seconds. Most amps will shut-down on over temp before they come close to clearing a fuse after long play with full power peaks.


I blew the fuse on a Cerwin Vega EXL-400.4 while bench testing it to determine output. I had it bridged at 4 ohms stereo and the 40 amp fuse went snap at 186 watts (well 27.x AC volts) per channel into 4 ohm dummy loads. It made it a whole 10 seconds before blowing the fuse.:laugh:


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## ChrisB (Jul 3, 2008)

cajunner said:


> or is it an amp that has it's components optimized for high dynamic range but can't sustain a sine wave?


This statement above caused me to have a "eureka moment" this weekend as to why a certain brand of high voltage amplifier didn't work out for me in any of my installs. Rather than bash, I've been trying to figure out the science as to why I was unique for having issues, and thanks to cajunner and conversations I had with other individuals over the last few days I finally understand why.

It was the "music" I was listening to! Lots of time while driving, I put on Drum and Bass or Dubstep because it is more of a background noise that will not encite an emotional response. Well, some of those tracks are nothing more than sine waves masquerading as music. In these tracks, the bass lines can pretty much go the whole 4 to 6 minute duration of the song from anywhere between 30 Hz and 100 Hz with little to no break.

As a result, my amplifiers would cut out or flat out shut down when I cranked the volume. I was wrongly led to believe by others that this was due to my electrical setup, even though my alternator/battery combinations were way above the vehicle and sound system requirements. In other words, I had no signs of voltage drop when things were cutting out and/or shutting down on me. My last thought was that my custom alternator in my then other, now only, vehicle was giving me grief because it runs near 15 volts. Nope, it was the material I was listening to.

Unfortunately, I have eclectic tastes in music. Sure I tend to play the various forms of electronic music since I used to DJ, but you can catch me listening to any of the following in one given trip: The Clash, Pink Floyd, Slayer, Mozart, Beethoven, Coltrane, Miles Davis, or Nine Inch Nails. Sometimes it is in that order!:laugh:

Thanks to cajunner, I now know the science behind why a certain brand of high voltage 12 volt amplifier did not work out for me and could probably NEVER work out for me. Thank you cajunner!


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## jimmy2345 (Jul 12, 2010)

ChrisB said:


> I blew the fuse on a Cerwin Vega EXL-400.4 while bench testing it to determine output. I had it bridged at 4 ohms stereo and the 40 amp fuse went snap at 186 watts (well 27.x AC volts) per channel into 4 ohm dummy loads. It made it a whole 10 seconds before blowing the fuse.:laugh:


So what is your point? Are you stating that Buss slow blow fuses can't perform as well as they claim, or your CV amp sucks a ton of current. 

What I find wierd is that you are always the one who had all the issues, but the other people using the same amps and fusing don't seem to.

The comment made above by asota is exactly correct. If you ran a larger LP amp on a faster blow type fuse you would need to use a considerable higher rating. The slow blow fuses are unique in the way they handle peak power for periods of time.


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## ChrisB (Jul 3, 2008)

jimmy2345 said:


> So what is your point? Are you stating that Buss slow blow fuses can't perform as well as they claim, or your CV amp sucks a ton of current.
> 
> What I find wierd is that you are always the one who had all the issues, but the other people using the same amps and fusing don't seem to.
> 
> The comment made above by asota is exactly correct. If you ran a larger LP amp on a faster blow type fuse you would need to use a considerable higher rating. The slow blow fuses are unique in the way they handle peak power for periods of time.


Guess you missed this sentence:



asota said:


> *Most amps will shut-down on over temp before they come close to clearing a fuse after long play with full power peaks.*


There, you should be able to see it now.

Edit: I forgot to mention that I had been doing four channel, 4 ohm, sine wave testing prior to the 2 channels bridged at 4 ohms. That amp was, uh, warm to the touch to say the least! 

I installed it in my sister's vehicle doing 4 ohm stereo to her components in the doors and two channels bridged to the sub in the trunk. I only had a 30 amp fuse on hand, and thus far (knocking on wood) she hasn't popped it. I'm sure she will let me know when she does! bahahahahahaha


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## jimmy2345 (Jul 12, 2010)

Explain yourself with words and not oversized bold red letters please. Was there a point you were trying to make or just argumentative babble again?

You argued against asota and then quoted him to verify your argument? You can't contradict yourself worse than that.


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## ChrisB (Jul 3, 2008)

jimmy2345 said:


> Explain yourself with words and not oversized bold red letters please. Was there a point you were trying to make or just argumentative babble again?
> 
> You argued against asota and then quoted him to verify your argument? You can't contradict yourself worse than that.





asota said:


> Most amps


Was my Cerwin Vega EXL-400.4 not an amp? 



asota said:


> will shut-down on over temp before they come close to clearing a fuse


Is the fuse blowing before the amp shut down not a direct contradiction to this statement? 



asota said:


> after long play with full power peaks.


Does being extremely warm to the touch due to a fairly long period of 4 ohm testing not count as "long play"?

The only contradiction I see, potentially, is that I did not use a slow blow fuse. Then again, asota equated slow blow fuses to Linear Power amplifiers not "most amplifiers" as stated in his last sentence which you seem to be so hung up on me contradicting myself over. Feeling a bit argumentative tonight, aren't we?

Then again, why in the hell are we even arguing semantics? I now know the scientific reason behind why Linear Power amplifiers didn't work for me. I'd say that is a revelation in and of itself. Finally, if I am wrong, please use a scientific reason to tell me why so I can further understand the errors of my ways.

EDIT: To asota, I made my statement as a joke. A bad joke, but a joke indeed, hence the: :laugh:

To jimmy2345: Why did you get your boxers in a knot over one of my bad jokes?


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## jimmy2345 (Jul 12, 2010)

ChrisB said:


> The only contradiction I see, potentially, is that I did not use a slow blow fuse.


Then you had no argument. You stated you blew a fuse with a lot less power yet it wasn't even a slow blow Buss fuse. Duh! The slow blow fuse is the key. The key to over riding the very argument you started this thread for. Put it to rest. No one denies that if you use any other type of fuse with a 4.1HVS you will need a larger fuse. Because this slow blow fuse can handle more current than it's rating for periods of time puts to rest your argument that LP is making claims against Ohms law. Stop trying to sway your initial argument and accept you are wrong.



ChrisB said:


> Then again, why in the hell are we even arguing semantics? I now know the scientific reason behind why Linear Power amplifiers didn't work for me. I'd say that is a revelation in and of itself. Finally, if I am wrong, please use a scientific reason to tell me why so I can further understand the errors of my ways.


Why are we? You started this thread. Close it now that you understand no one is trying to make claims against Ohms law.


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## ChrisB (Jul 3, 2008)

jimmy2345 said:


> Then you had no argument. You stated you blew a fuse with a lot less power yet it wasn't even a slow blow Buss fuse. Duh! The slow blow fuse is the key. The key to over riding the very argument you started this thread for. Put it to rest. No one denies that if you use any other type of fuse with a 4.1HVS you will need a larger fuse. Because this slow blow fuse can handle more current than it's rating for periods of time puts to rest your argument that LP is making claims against Ohms law. Stop trying to sway your initial argument and accept you are wrong.


Well... Actually on second thought, forget it because continuing this discussion will just result in me being dragged down to your level and being beat with experience.:laugh: 

It's just not worth it... You win this argument. Happy now?



jimmy2345 said:


> Why are we? You started this thread. Close it now that you understand no one is trying to make claims against Ohms law.


Actually, I started this thread to dispel the myth that "High voltage 12v amplifiers are better than high current 12v amplifiers" and it took a sidetrack into Ohm's law.

So to recap... In my situation, a high voltage, 12 volt, class ab amplifier is NOT the right tool to drive a highly inefficient, modern day, small enclosure subwoofer in any of my setups. Not even if I wire it to 8 ohms.

Furthermore, if I were to purchase a high voltage class ab amplifier capable of meeting the weird demands I have, it would be the size of a surfboard, and again would not be the product for me. I can't be the only one who is tired of devoting a ton of real estate to mount large amplifiers in an automobile!


----------



## narvarr (Jan 20, 2009)

ChrisB said:


> Well... Actually on second thought, forget it because continuing this discussion will just result in me being dragged down to your level and being beat with experience.:laugh:
> 
> It's just not worth it... You win this argument. Happy now?
> 
> ...


Don't know if you knew this, but some of the LP amps had switches on them for low impedence loads, i.e., sub duty. Big class A/B amps take up a lot of space, but some like their sound better than class D. I myself am switching from a pair of rather small DLS full range class D amps to a trio of huge Diamond Audio class A/B high current monsters. To me, I would rather have to find room for them then to give up anything from a sound standpoint. I say to each their own...

Sent from my X10i using Tapatalk


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## ChrisB (Jul 3, 2008)

narvarr said:


> Don't know if you knew this, but some of the LP amps had switches on them for low impedence loads, i.e., sub duty.


Actually, they had internal power supply taps to set the rail voltage. You set them to 2 ohms for 2 ohm stereo or 4 ohms bridged. You left them at 4 ohms for 4 ohm stereo or 8 ohms bridged. The only ones with switches that I owned were on the non-IQ models where the switch inverted one channel for bridged mono operation. Well, and for the useless clip, I mean DIP board in the 5002.



narvarr said:


> Big class A/B amps take up a lot of space, but some like their sound better than class D. I myself am switching from a pair of rather small DLS full range class D amps to a trio of huge Diamond Audio class A/B high current monsters. *To me, I would rather have to find room for them then to give up anything from a sound standpoint.* I say to each their own...


That's another argument for another thread regarding something that that is being installed in a mobile environment that can have a noise floor as low as 60 dB or as high as 90 dB at highway speed.


----------



## jimmy2345 (Jul 12, 2010)

ChrisB said:


> Actually, I started this thread to dispel the myth that "High voltage 12v amplifiers are better than high current 12v amplifiers" and it took a sidetrack into Ohm's law.





ChrisB said:


> In another thread that got totally out of hand, it was touted by some that high voltage amplifiers were better than high current amplifiers. They started talking about this 12v amplifier that had 120 volt DC rails inside of it stating that it can make all kinds of power all day long with minimal current draw, thus violating the properties of ohm's law.




Doesn't look like a sidetrack to me. From your initial statement to start this thread you started your usual crap. Is it still referred to as a sidetrack when the OP brings up the topic right from the start???


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## ChrisB (Jul 3, 2008)

jimmy2345 said:


> Doesn't look like a sidetrack to me. From your initial statement to start this thread you started your usual crap. Is it still referred to as a sidetrack when the OP brings up the topic right from the start???


I already said that you won but since you like to argue... Let's look at some specs on the other Linear Power amplifiers that I owned:

The DPS 500 had 30 amps of fusing and claimed to produce 500 watts RMS bridged. 30 x 14.4 = ? Now let's factor in efficiency...

The 2.2 HV had 40 amps of fusing and claimed to produce 600 watts RMS bridged. 40 x 14.4 = ? Again, let's factor in efficiency.

Now, let's take it a step further where certain fanbois told me those two amplifiers were grossly underrated. I was told I should have expected 700 watts RMS from the DPS 500 and close to 1,100 watts RMS from the 2.2 HV. Now that would be a violation of Ohm's Law if I ever saw one!


----------



## trojan fan (Nov 4, 2007)

ChrisB said:


> I already said that you won but since you like to argue... Let's look at some specs on the other Linear Power amplifiers that I owned:
> 
> The DPS 500 had 30 amps of fusing and claimed to produce 500 watts RMS bridged. 30 x 14.4 = ? Now let's factor in efficiency...
> 
> ...



Why does LP take part in this type of marketing of their amps?


----------



## jimmy2345 (Jul 12, 2010)

ChrisB said:


> I already said that you won but since you like to argue... Let's look at some specs on the other Linear Power amplifiers that I owned:
> 
> The DPS 500 had 30 amps of fusing and claimed to produce 500 watts RMS bridged. 30 x 14.4 = ? Now let's factor in efficiency...
> 
> ...


Then why don't you just read the DPS500 manual instead of believing these so called "fanbois". The manual states a 40 amp fuse, and also states 420 x 1 at 14.4 volts. Feel better now?

Then go read the manual for the 2.2HV where it clearly states 185 x 2 with a 40 amp fuse at 4 ohm stereo. Sounds about right to me. Then 600 x 1 at 4 ohm bridged and tells you that it can draw 50 amps when ran at 2 ohm stereo (4 ohm bridged). Sounds about right to me again. So if you want to run the 2.2HV at 4 ohm bridged you would need to up the fuse.

Anything else you need cleared up? It's all in the manual. Start calling out the so called "fanbois", as you call them, and not LP.


By the way, great way to cover up your last comments about others sidetracking this thread when you were called out for starting this very topic. Others may have a short term memory, but I don't. Are you ready to put this all to rest? You have been set straight 3 times now in this one thread.


----------



## ChrisB (Jul 3, 2008)

jimmy2345 said:


> Then why don't you just read the DPS500 manual instead of believing these so called "fanbois". The manual states a 40 amp fuse, and also states 420 x 1 at 14.4 volts. Feel better now?
> 
> Then go read the manual for the 2.2HV where it clearly states 185 x 2 with a 40 amp fuse at 4 ohm stereo. Sounds about right to me. Then 600 x 1 at 4 ohm bridged and tells you that it can draw 50 amps when ran at 2 ohm stereo (4 ohm bridged). Sounds about right to me again. So if you want to run the 2.2HV at 4 ohm bridged you would need to up the fuse.


Sorry, I read this and all I saw was read the manual, blah blah blah. I haven't owned these products for nearly two years now so I really don't care about their operation. If it makes you feel any better, I have no plans to own any more either, unless they happen to come installed in a vehicle that I purchase. Even then they will either be sold or featured on a youtube video being detonated with tannerite.



jimmy2345 said:


> Anything else you need cleared up? It's all in the manual. Start calling out the so called "fanbois", as you call them, and not LP.


I kind of did. Does this ring a bell:




ChrisB said:


> They (implied to mean fanbois) started talking about this 12v amplifier that had 120 volt DC rails inside of it stating that it can make all kinds of power all day long with minimal current draw, thus violating the properties of ohm's law.


There is NO such thing as major power with minimal current draw in a high voltage situation. As I stated earlier, supply voltage and supply current are necessary to produce said power, regardless of if it is a high voltage or high current product.



ChrisB said:


> By the way, great way to cover up your last comments about others sidetracking this thread when you were called out for starting this very topic. Others may have a short term memory, but I don't. Are you ready to put this all to rest? You have been set straight 3 times now in this one thread.


I see your problem... you tried to guess what I was thinking. That is a HUGE mistake on your part because Keith Barry, you are not!


----------



## jimmy2345 (Jul 12, 2010)

Yet, more babble when proven wrong. You call out a company for defying Ohms law, someone else states the facts, and you jump to other comments to avoid simply stating; I am sorry, I am incorrect.

Then you go on to state you don't care about the products yet YOU are the one who always starts these threads directed at Linear Power. Your hatred shows how much you care. Actions speak louder than words and your actions are very loud. Yet, nothing you ever state rings true just as in this very thread.


----------



## ChrisB (Jul 3, 2008)

jimmy2345 said:


> Yet, more babble when proven wrong. You call out a company for defying Ohms law, someone else states the facts, and you jump to other comments to avoid simply stating; I am sorry, I am incorrect.


Woah, woah, woah... Back that train up. I made NO mention of brand or company until post 38. Of course, I do find it quite ironic that I made no mention of brand until post 38, yet both Randall and yourself, known Linear Power advocates, managed to make their way into this thread LONG before then!

As Cajunner pointed out, Linear Power wasn't the only manufacturer with a high voltage, 12 volt, class ab, car audio amplifier. Also, while Linear Power did not work for me, I'd be willing to bet that most of the other high voltage 12v amplifiers would have had similar results except for maybe the US Amps high voltage surfboard.



jimmy2345 said:


> Then you go on to state you don't care about the products yet YOU are the one who always starts these threads directed at Linear Power.


You're the one who told me to RTFM on products that I no longer own. In all honesty, why should I care about something I no longer own?



jimmy2345 said:


> Your hatred shows how much you care.


Where in this thread did I say I hated anything or any brand? Also, I'm not talking about scouring the forum and finding prior posts, I'm talking about THIS tread. Let's go, show me.

In fact, now that I better understand the reason WHY Linear Power didn't work out for me, saying I hate the product is kind of strong. Knowing what I know now, I used the wrong tool for the job, plain and simple.



jimmy2345 said:


> Actions speak louder than words and your actions are very loud.


As do your actions. You jump in, want to argue, then as usual, have nothing scientific to back up your trollish fodder. Actions eh? Yours speak loads about you!



jimmy2345 said:


> Yet, nothing you ever state rings true just as in this very thread.


Didn't I ask you for a scientific reason to prove me wrong? Well, I'm still waiting.


----------



## ChrisB (Jul 3, 2008)

trojan fan said:


> Why does LP take part in this type of marketing of their amps?


You see, that is what some don't get. Linear Power NEVER made absurd claims about how their products that violated Ohm's Law. It is the fanbois who make them all over the internet and even when you talk to them. Sadly, no one ever bothers to correct them. Then, if you do correct them, you are labeled a hater. Go figure...


----------



## jimmy2345 (Jul 12, 2010)

ChrisB said:


> Woah, woah, woah... Back that train up. I made NO mention of brand or company until post 38. Of course, I do find it quite ironic that I made no mention of brand until post 38, yet both Randall and yourself, known Linear Power advocates, managed to make their way into this thread LONG before then!





ChrisB said:


> Post 1 - In another thread that got totally out of hand, it was touted by some that high voltage amplifiers were better than high current amplifiers. They started talking about this 12v amplifier that had 120 volt DC rails inside of it stating that it can make all kinds of power all day long with minimal current draw, thus violating the properties of ohm's law.


A specific name doesn't need to be stated. Your reference was enough.



ChrisB said:


> Where in this thread did I say I hated anything or any brand? Also, I'm not talking about scouring the forum and finding prior posts, I'm talking about THIS tread. Let's go, show me.


Now you are arguing like a 6 year old child. Any rational person can see your hatred. You call out numerous LP amps in this one thread stating they make claims to violate Ohms law. Then you were set straight and tried to change the subject to other babble. As I stated, your actions speak loudly. If your wife cheats on you, but comes home and whispers "I love you" in your ear would you believe her. I think not. You are doing to same....showing hatred with your actions of starting threads directly related to LP without actually putting the name in the title. We all see how malicious you are.





ChrisB said:


> As do your actions. You jump in, want to argue, then as usual, have nothing scientific to back up your trollish fodder. Actions eh? Yours speak loads about you!
> 
> Didn't I ask you for a scientific reason to prove me wrong? Well, I'm still waiting.



What facts do you need? I provided all that was needed to show this thread is another misrepresentation attempt on your part. You quote Ohms law on the daily here and state LP is claiming to defy it so why don't you do the calculations yourself with specs taken DIRECTLY FROM THE MANUAL, instead of specs you had wrong but thought you had right.


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## jimmy2345 (Jul 12, 2010)

ChrisB said:


> You see, that is what some don't get. Linear Power NEVER made absurd claims about how their products that violated Ohm's Law. It is the fanbois who make them all over the internet and even when you talk to them. Sadly, no one ever bothers to correct them. Then, if you do correct them, you are labeled a hater. Go figure...


Isn't it funny how your tune changed from post 1 to this post but you have yet to state you are wrong and probably should do your homework before you start making claims.

Then you try to use my exact words against me. I am the one who set you straight with this information, and then you state that I called you a hater because of it. The fact is you were making claims that LP claims to violate Ohms law and that is where you were called a hater.....rightfully so and proven wrong. 

Don't act like from the start you were calling the "fanbois" wrong when it was actually LP you were calling out. Do I need to do a search for how many posts you have made on this forum of LP claiming to defy Ohms law?


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## ChrisB (Jul 3, 2008)

jimmy2345 said:


> Isn't it funny how your tune changed from post 1 to this post but you have yet to state you are wrong and probably should do your homework before you start making claims.


My tune stayed the same, I just expanded on it. You still haven't told me why high voltage 12 volt amplifiers are better than 12 volt high current amplifiers for my situation. I'm still waiting to read your revolutionary words of wisdom... Which will probably never happen.



jimmy2345 said:


> Then you try to use my exact words against me. I am the one who set you straight with this information, and then you state that I called you a hater because of it. The fact is you were making claims that LP claims to violate Ohms law and that is where you were called a hater.....rightfully so and proven wrong.


There you go again... I said the fanbois made the claims. Remember Frank, that pawn shop owner in Florida? He told me his 8002SW made 1,600 watts RMS and he had a pair of them on a 150 amp ANL fuse. He also said he competed in SPL and kept bragging about his score on the audio control. So, that's 3,200 watts RMS on 150 amps of fusing, with a normal fuse, running subwoofers in SPL. I'd call that an over-exaggerated claim that violates Ohm's Law if I've ever seen one.

In fact, I even took him up on his bet when he told me his amplifiers were more efficient than any class D amplifier made today and I never heard from him again after that. Actually, there were several of us who responded to his challenge only to have him drop off the face of the earth.



jimmy2345 said:


> Don't act like from the start you were calling the "fanbois" wrong when it was actually LP you were calling out. Do I need to do a search for how many posts you have made on this forum of LP claiming to defy Ohms law?


For what it is worth, I heard similar, over-exaggerated power claims from the Orion, Rockford Fosgate, Soundstream, and Zapco fanbois. Also note, I said THIS thread because I had an epiphany over the weekend with the fact that I picked the wrong tool, a high voltage 12 volt amplifier, for the job of powering a subwoofer with my musical tastes. 

I've come a long way because I want to understand the science behind the sound and the reason why something didn't work in my particular situation. It just so happened that this very thread enlightened me with regards to a two year old complaint that I had. While you just see this as yet another Linear Power bashing thread, I see this as the answer to WHY they didn't work for me. Furthermore it is better than the answer I received two years ago when I was told, and I quote "Try listening to real music." What the hell kind of response was that?


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## envisionelec (Dec 14, 2005)

ChrisB said:


> Remember Frank, that pawn shop owner in Florida? He told me his 8002SW made 1,600 watts RMS and he had a pair of them on a 150 amp ANL fuse. He also said he competed in SPL and kept bragging about his score on the audio control. So, that's 3,200 watts RMS on 150 amps of fusing, with a normal fuse, running subwoofers in SPL. I'd call that an over-exaggerated claim that violates Ohm's Law if I've ever seen one.


Bottom line: The 8002SW has +/-70V rails. This translates into about +/-60V of actual useable output swing. I'm being generous.

That's 900W into 4 ohms.

And that's all you'll get.


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## Cablguy184 (Oct 7, 2010)

envisionelec said:


> Bottom line:
> The 8002SW
> 
> That's 900W into 4 ohms.


I agree with this ... non modified amp sounds close ... possibly 8 ohms ... 
I will have to ask Ray to be sure ...


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## envisionelec (Dec 14, 2005)

cajunner said:


> I like Linear Power.
> 
> To me, they have always been an expensive proposition, even way back when.
> 
> ...


I freaking love the way they look. Super simple, industrial. Candy colored. :laugh:


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## GTI-DNA (Nov 4, 2010)

Ok, after reading this thread, I have a headache. As an original owner of 2 vintage 1990 LP's I have just one question:

How can they deliver the same wattage into both 4 and 8 ohm loads??

Real question, not dissing, starting an argument, etc.

I really would like to know.

No "fanboy" here, they are just the only real amps I have bought that are still working (Punch 45 circa 1987 burned up YEARS ago)


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## envisionelec (Dec 14, 2005)

GTI-DNA said:


> Ok, after reading this thread, I have a headache. As an original owner of 2 vintage 1990 LP's I have just one question:
> 
> How can they deliver the same wattage into both 4 and 8 ohm loads??
> 
> ...


If it has a "4 ohm - 2 ohm" switch, it's because the 2 ohm voltage rails are lower than the 4 ohm rails. Maybe 35V for 4 ohms and 25V for 2 ohms. It keeps the output devices from blowing up.


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## TrickyRicky (Apr 5, 2009)

envisionelec said:


> If it has a "4 ohm - 2 ohm" switch, it's because the 2 ohm voltage rails are lower than the 4 ohm rails. Maybe 35V for 4 ohms and 25V for 2 ohms. It keeps the output devices from blowing up.


CORRECTO MUNDO. Isn't this compareable to the RIPS system JL uses?


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## GTI-DNA (Nov 4, 2010)

envisionelec said:


> If it has a "4 ohm - 2 ohm" switch, it's because the 2 ohm voltage rails are lower than the 4 ohm rails. Maybe 35V for 4 ohms and 25V for 2 ohms. It keeps the output devices from blowing up.


Only my 952 has said switch. What about my 452?


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## TrickyRicky (Apr 5, 2009)

ChrisB said:


> There you go again... I said the fanbois made the claims. Remember Frank, that pawn shop owner in Florida? He told me his 8002SW made 1,600 watts RMS and he had a pair of them on a 150 amp ANL fuse. He also said he competed in SPL and kept bragging about his score on the audio control. So, that's 3,200 watts RMS on 150 amps of fusing, with a normal fuse, running subwoofers in SPL. I'd call that an over-exaggerated claim that violates Ohm's Law if I've ever seen one.


I remember him. The truth is those amps didnt make that much power it just sounded like they did, lol. Those are 800watt amplifiers, how in the world could anyone double the power? I know what Ray does when he modds the 8002SW and trust me in no way or shape or form does he double the power. And RAY NEVER said the power doubles. Its the fanbois you cant blame them when they are trying to get the most $$$ out of their amps.


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## ChrisB (Jul 3, 2008)

GTI-DNA said:


> Only my 952 has said switch. What about my 452?


Looks like the 452IQ specifies taps on the bottom plate:









Yet I don't see them in the amp:


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## TrickyRicky (Apr 5, 2009)

GTI-DNA said:


> Only my 952 has said switch. What about my 452?


On the smaller LP's they didnt up the power with higher impendance. So in this case you would notice a smaller increase when using it at 2-ohms stereo.


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## TrickyRicky (Apr 5, 2009)

ChrisB said:


> Looks like the 452IQ specifies taps on the bottom plate:
> 
> 
> 
> ...


You do know that that diagram was used more than just on one amp? If the amp doesnt have the internal taps, then it doesnt apply to it.


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## ChrisB (Jul 3, 2008)

TrickyRicky said:


> You do know that that diagram was used more than just on one amp? If the amp doesnt have the internal taps, then it doesnt apply to it.


Yes I do, but look at the model number on it!


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## TrickyRicky (Apr 5, 2009)

What about it, it has 452IQ below the diagram they used (which is the same diagrams they used for a lot of the 2-channel amps). If you think of it the way your thinking about it, then consider it a TYPO, lol.

Check the manual 452IQ Manual, it does not mention anything about switching TAPs.

This reminds me about the whole "BATTERIES" problem that we seem to have. WHY THE FUDGE do we need a diagram showing us how batteries go when we all know the negative part goes to the springy side, lol. Oh I remember for people that are super dumb and need someone to hold their hands when installing batteries. I say that because I've seen Hexi Base rant about this battery problem, that was NEVER a problem. Just how some dumb people are so dumb that they WANT a universal battery insert. That way if you happen to install the battery backwards the circuitry would recognize it and fix the problem for the IDIOT.

Why the hell did I bring that up, I dont know, lol.


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## GTI-DNA (Nov 4, 2010)

Thanks guys. I looked inside and didn't see a tap. All I know is that for 22.5 watts per channel specs, It's has damn good output.


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## subwoofery (Nov 9, 2008)

Please guyz, those that don't want to answer the original post question, please leave this thread. I'm sick of reading all this nonse-crap because someone implies that one brand is good/bad/****. 
I just want to learn from those that know much more than me and that is why I still come to DIYMA. 
When I first read the OP, I didn't see anything against any brand... Don't know why some guyz feel that he created this thread just to talk down about LP... 

Been reading a bit about HV/HC lately and would like to know if what I feel is at least half correct  
I understand that when driving higher impedance (above 4 ohm), HV is a better topology - while lower impedance are better left to HC amps. 

Now, my concern right now is to find the best midbass amplifier for my system. 
Most know that midbass amps can get hot real quick and I also find that the midbass amp can run out of juice faster than the sub amp on dynamic peaks. 
A few weeks ago, I read an old test from an Italian magazine that shows how dynamic the Steg MSK 50SC really is (HC topology). 
With a load of 1 ohm and an impulse of 40ms, the Steg shows an impressive 6.5dB of dynamic headroom... Yes 6.5dB with an impulse of 40ms (most testers do 20ms). 

Right after browsing through the test, I remembered about Phass amps and their "weird/cool" topology. The feature a HC topology that puts out constant current @ 4, 8 and 16 ohm. 
^ Don "Buzzman" said that his 50rms Phass RE50 sounded more powerful on his mid than his other Phass amp 4 channels bridged on it (200rms x 2). 

What I really want to know is, are HC really that good and be the best amp for my application (midbass duty)? Even if the load was high (4 ohm or 8 ohm)... 
And by using a HC amp at a higher load, wouldn't that result in huge headroom and nice bump in efficiency? 

Kelvin


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## envisionelec (Dec 14, 2005)

subwoofery said:


> What I really want to know is, are HC really that good and be the best amp for my application (midbass duty)? Even if the load was high (4 ohm or 8 ohm)...
> And by using a HC amp at a higher load, wouldn't that result in huge headroom and nice bump in efficiency?
> 
> Kelvin


All things being equal, no - unless your midbasses have a wide variation in impedance (unlikely unless you have a parallel trap or something).

A high current amp is a very real thing an engineering standpoint, but a largely misunderstood component of _any_ amplifier. The amplifier is going to deliver a certain amount of voltage at a certain amount of current - and that is constrained by two primary components: 1. Rail Voltage 2. Feedback/Gain and lesser by protection circuits and emitter resistors...

If an amplifier isn't current limited artificially (which is anathema!), it will continue to pump current until the output devices fail. Simply adjusting this "VI" current limiter doesn't make a "high current" amp. At least, not if you want it to survive. Another big issue with driving amps into low impedances is a phenomenon called beta droop. So your buddy says he can drive his 2ohm-stable amp at 0.25 ohm "all day long" - well, sure - but he's getting _less power_ than he would at 4 ohms and significantly degrading the reliability of the amp. So why does this happen? It's a physical property of bipolar output devices. As they deliver more current, they get hotter - and gain (HFe) drops. It's already only about 5-10, but can drop to less than 1 (less than unity gain!!) when they're about to fry. What kills them? Base-emitter overcurrent. You can only push so much current through that junction, and an amp that is attempting to drive your 0.25 ohm load is trying to maintain a given voltage. It will keep pushing and pushing those outputs until they either succumb or deliver. Evil! This is another reason simple VI limiters across the emitter resistors are a rather foolish way to monitor current in car amplifiers because they only implicitly know how much current is going into the output devices.

Increasing the number of output devices gets you halfway there. Increasing base drive current _with_ lots of output devices gets you there completely. Guess what? You don't have to change much else in the front end of the amp. All that stuff is voltage amplification - and since you're already limited to the rails (or slightly above for some designs), you're only concerned about current.

On a given amplifier, using physically bigger output devices does not mean you get more power. Using higher "wattage" transistors gains you nothing. Oh - and my favorite - judging an amplifier's output capability by the output devices' part numbers. That's always good for a laugh.

I should write a blog on car amplifiers. Seriously...I think it would do well.


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## envisionelec (Dec 14, 2005)

ChrisB said:


> Looks like the 452IQ specifies taps on the bottom plate:
> 
> 
> Yet I don't see them in the amp:


Hmm. This is a Class B amp(!). I see a bias compensation transistor but no bias generator circuit unless those Dale resistor packs also contain diodes. 

No wonder these last forever. They fold under pressure. Nice.


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## ChrisB (Jul 3, 2008)

I know that I am going off on a tangent here, but I tend to remember the Peavey CS 800 and CS 1200 being "high voltage" amplifiers from my DJing days. My CS 800 weighed 45 pounds and was capable of providing 400 watts RMS per channel at 4 ohms or 800 watts bridged at 8. As you can see, that amplifier was massive and had fan forced cooling to boot. With that stated, how on earth can some of the 12 volt, high voltage variants be so much smaller and lighter while touting the same or more power using conventional cooling through a heat sink? Something's not adding up here...

On another note, I know for a fact that the caps in the CS 1200 store a nice wallop over time. I watched one of my friends weld a screwdriver to one while disassembling it to clean. It literally scared the sh*t out of him, and me too since I was standing right there!


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## Hispls (Mar 12, 2008)

MTU_Husky said:


> That is an absolute impossibility, the laws of physics, namely Ohm's Law proves this. To produce 900 watts on a 14.4v system you have to draw 62.5 amps at 100% efficiency, with 80% efficiency you need to draw 78.125 amps, this is an absolute, YOU CANNOT VIOLATE THIS!! This is especially true with pink noise since it is a constant signal. On a peak the amp could deliver more power because of the storage caps inside of the amp however these will be draing after a couple of transients, on a long pink noise tone this will not really be storing any power and you will be drawing the full current needed to drive the amp.


Pink noise draws much less current than sine waves FYI.

That being said I've ran my Leviathan for better than a year now, mostly 4 ohms per channel, but for about a month with a pair of channels strapped to 3 ohm and never popped my 60A fuse. I run my stuff pretty hard at times.


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## subwoofery (Nov 9, 2008)

envisionelec said:


> All things being equal, no - unless your midbasses have a wide variation in impedance (unlikely unless you have a parallel trap or something).
> 
> A high current amp is a very real thing an engineering standpoint, but a largely misunderstood component of _any_ amplifier. The amplifier is going to deliver a certain amount of voltage at a certain amount of current - and that is constrained by two primary components: 1. Rail Voltage 2. Feedback/Gain and lesser by protection circuits and emitter resistors...
> 
> ...


Good read thanks... 
I know that you don't really like the term "headroom" - paying for an amp that puts out power some of the time. 
But wouldn't that be a way to make your amp sound bigger than it really is while keeping it cool during hard listening? 

Also regarding my concern... You believe I should look at a good HV amp for midbass duty? Any example of good designs? 

Kelvin


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## narvarr (Jan 20, 2009)

subwoofery said:


> Good read thanks...
> I know that you don't really like the term "headroom" - paying for an amp that puts out power some of the time.
> But wouldn't that be a way to make your amp sound bigger than it really is while keeping it cool during hard listening?
> 
> ...


I see you logic and agree, but I think this would also help to lower the noise floor as well. My plans for my install is to use one of my 4 channel amps bridged at 4ohm. This will give me 400 watts for each midbass but I wouldn't be using near that much power.

Sent from my X10i using Tapatalk


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## Luke352 (Jul 24, 2006)

Hispls said:


> That being said I've ran my Leviathan for better than a year now, mostly 4 ohms per channel, but for about a month with a pair of channels strapped to 3 ohm and never popped my 60A fuse. I run my stuff pretty hard at times.


I've had my Lev bridged on 3 ohms since I got it new, I checked with Steve (Zed) to ensure I wouldn't have any issues and thats when he told me something about Class D amp output devices don't suffer from secondary breakdown. So loading it down further won't do much harm, the limiting factor will be the current ability of the output mosfets and the power supply.



subwoofery said:


> Good read thanks...
> I know that you don't really like the term "headroom" - paying for an amp that puts out power some of the time.
> 
> 
> Kelvin


My understanding is when manufactures claim xdb headroom in most cases it's just a sign of a power supply that sags and can't hold a steady voltage.


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## TrickyRicky (Apr 5, 2009)

I just say "use only what YOU like." If its a class a/b amp then so be it, if its a class d amp oh well. No need to argue over which one is better or which power supply sags, or who pulls more current more heat which is more efficient. Just use what you enjoy the most.

I say that because there will always be someone that will argue with you, dont matter if your right or wrong, so take my advice and use what the hell you want and let others use what they want, with out saying "oh your amp is less efficient, your power supply sags, ect ect".

I know Chris started this thread pretty much to know which one would be better to use (for HIM). Well if he didnt get his answer here it is "CLASS D", but wait a minute aren't those LUNARS class A/B??. I in the otherhand will continue to use A/B and really dont care what the EXPERTS have to say about that, because I simply enjoy the A/B more than the class D.


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## ChrisB (Jul 3, 2008)

TrickyRicky said:


> I know Chris started this thread pretty much to know which one would be better to use (for HIM). Well if he didnt get his answer here it is "CLASS D", but wait a minute aren't those LUNARS class A/B??. I in the otherhand will continue to use A/B and really dont care what the EXPERTS have to say about that, because I simply enjoy the A/B more than the class D.


In addition to the normal Lunar amplifiers that I use on mids and highs, I have a custom built L2200 that was designed for high current mode with a lower rail voltage. To date, I still haven't installed it due to lack of motivation.:laugh: Also, the L1500, currently in my wife's car, is one of the smallest and most efficient class ab amplifiers I have ever run across for high current mode.

Next time I make an amplifier purchase, it will more than likely be Arc KS or JL Audio HD because I am tired of devoting tons of real estate to huge amplifiers in a reproduction medium that is far from ideal. With 20 minutes and a set of $500 KRK Rokit 8s, I can have a computer sounding better than most cars with 80 hours of install time and thousands of dollars spent on the equipment. Unfortunately, car audio is what it is.

Since everyone likes to use car analogies for amplifiers, I think of class ab amplifiers as muscle cars in that they are HUGE with lots of power while getting 8 MPG in the city. OTOH, I think of the class d amps like my buddy's old 600 WHP CRX that could smoke most muscle cars and still get 22 MPG in the city. Class gh, well, those would be like a Toyota Prius or that new Lexus thing.:laugh:


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## envisionelec (Dec 14, 2005)

TrickyRicky said:


> I just say "use only what YOU like." If its a class a/b amp then so be it, if its a class d amp oh well. No need to argue over which one is better or which power supply sags, or who pulls more current more heat which is more efficient. Just use what you enjoy the most.
> 
> I say that because there will always be someone that will argue with you, dont matter if your right or wrong, so take my advice and use what the hell you want and let others use what they want, with out saying "oh your amp is less efficient, your power supply sags, ect ect".


IIRC, this is DIYMA - *Scientific *Car Audio - *Truth in Sound Quality*. I'm explaining the *science* - the part that is not subjective.

It's not an argument/hypothesis - it's amplifier design. Subjectivity has _nothing_ to do with it.


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## ChrisB (Jul 3, 2008)

Cablguy184 said:


> I agree with this ... non modified amp sounds close ... possibly 8 ohms ...
> I will have to ask Ray to be sure ...


You still haven't answered my question:



ChrisB said:


> Answer this question for me, just how many people compete against you in your SQ class at each USACi event?


At the TOP DOLLAR PAWN event held on 05/07/11 it looks like you placed 1 out of 1. At the Big Daddy's Pawn event held on 05/21/11, it looks like you placed 1 out of 1. At the TOP DOLLAR PAWN event held on 06/11/11, you again placed 1 out of 1. I'm starting to see a pattern here...

So let me get this straight. I'm worthless for not competing, but you are better for competing against no one? That looks like what you were trying to tell me here:


Cablguy184 said:


> So you do not compete and you do not have a sound quality vehicle to back up your actions ...
> Just like a person that does not vote ... They should not complain or even talk about politics ... absolutely worthless ...


Well?

Edited to add: Looks like you placed last at finals last year. So again, I implore you to elaborate on just what it is that makes you so much better than me just because you compete?


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## I Need Bass (Jun 2, 2009)

LP amps should be able to sustain a sine wave ...

...I'm going to say that most high voltage amps designed and stated to be such a topology, are best operated as full range or highs and not specifically for low or mid bass apps.

This is not the case for US Amps, however. Even their high voltage series, the USA-XXX line, was designed to drive de-facto, or semi- low impedance loads without complaint.

This is more a matter of distinguishing stability from the .5 ohm variant that was developed as a current monster to evade competition rules back in the day, in that whole perversion of wattage ratings that became legend way back when.[/QUOTE]


I LOVE IT...I still currently us both of those amps in different cars to drive my systems....DPS500 on a JLw610, DPS500 on some CTD coax's, DPSQ50 on comp's up front all on a stock electric system in my HYundai LOL

I also have 2 bigUSA400's and a150X from US Amps driving my 1/2 ton pick's system on stock electric for years and NO ISSUES


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## I Need Bass (Jun 2, 2009)

ChrisB said:


> the US Amps high voltage surfboard.
> 
> 
> 
> ...sounds like my USA400's been in your car again....:laugh:


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## ChrisB (Jul 3, 2008)

I Need Bass said:


> LP amps should be able to sustain a sine wave ...
> 
> ...I'm going to say that most high voltage amps designed and stated to be such a topology, are best operated as full range or highs and not specifically for low or mid bass apps.
> 
> ...


I had a DPSQ50 and a DPS500. I think I made $1,400 or $1,500 when I sold them. I only paid $150 or $175 for the Q50 and the 500 was payment for doing a tax return. Unfortunately, that combo was not enough power for me.


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## wheelieking71 (Dec 20, 2006)

i have a question that would at first seem irrelevant. but really is the root of why "high current" amps exist. what is the advantage of running stupid low impedence on the substage?


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## wheelieking71 (Dec 20, 2006)

its been about shrinking the size of amps, subs, and sub enclosures for the last 20sum odd years. thats the bottom line right? im not trying to make this about subs, but you just cant discuss the difference between "high power", and "high current" without first knowing why "high current" exists. i do not know the science behind it. but i do know that for at least 15 years amp manufacturers preyed on customers with this sales pitch: "1ohm stable!". ever since the original kicker "C" series, cones have been getting heavier, Xmax has been growing, and the power needed to get the same output from 1cube, as you used to from 2 or 3cubes has been growing. "high current" amps dont exist because of the power requirements of the front stage. its all about subs! and lots of them. if this hobby was truly about sound quality people would still be rocking the original JBL 15Gti (yea, the original model with the pleated surround!) in a 3cube box, with 2-300 watts being plenty. there would be no need for 1ohm anything. and 12mm of Xmax would make the hair on your neck stand up! (ask me how i know) but thats not what its about. car audio, as a whole is about loud! (true SQ guys are few and far between) and people arent willing to give up thier whole trunk, or hatch to get perfect bass. so cones got heavier, Xmax got longer, and power requirements went WAY up. its simply a compromise of acceptable sound quality, and how much realestate the hobbyist is willing to give up. so, from a PURELY sound-quality standpoint, i ask, is there any advantage to running low impedence subwoofers? i think not. but manufacturers cant market from a purely sound-quality standpoint. they would go belly up, because its all about lots of bass, in a small space. just my opinion. not worth much, but it has been formed by watching thousands of great amps die because they were pushed to do things they really werent engineered to do well. and it happened because of marketing!


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## ChrisB (Jul 3, 2008)

Actually, it is more cost effective to build a high current amplifier that can sustain a 30 second burp at 1 ohm versus building a high voltage amplifier that can do the same thing at 8 ohms. After all, they are only working with a 12 volt DC electrical system here and are bound by the constraints of that limitation. 

EDIT: As I learned from personal experience, high voltage amplifiers for subwoofer use just can't sustain a 45 second 50Hz tone from a modern day dubstep or drum and bass track. You can ask my wife how happy I was when I couldn't even make a short trip to the gym without my subwoofer amplifier shutting down. Furthermore, you can ask her how livid I was when I contacted a certain someone and was told that those amplifiers were designed to reproduce "real music." Of all the times I wished I had the super power ability to reach through the phone and slap someone, that was one of them!

As for low impedance sound quality on subwoofers, in an area of the audible spectrum where our ears are least sensitive to changes in frequency, installed in a mobile environment... Well, you should see where I am going with that one...


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## wheelieking71 (Dec 20, 2006)

but the title of the thread is "high voltage better than high current". better for what? are we talking SPL? or "sound quality". if we are talking sound quality, with no constraints (enclosure limitations) there is no need for high current. high current exists because of power requirements dictated by enclosure size. there is a whole lot more to it than that, i know! but if everybody could afford to have a 3-5cube sub enclosure, and all they were worried about was accurate reproduction of the recording, there would be no need for high current. so, it becomes not a matter of which is better. it becomes a matter of which do you need! there is no need for a "30sec. burp" in a sound quality environment. the general car audio public is only worried about how loud it is. and consequently they associate volume with sound quality! so the premise of the thread is flawed. you need to add, "better for what?"


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## sonikaccord (Jun 15, 2008)

I think it has to do with the 12V source. It all starts from there. To build a high voltage supply you have to up that voltage to X amount of volts to get a required output. Well ohm's law says you can get power from either an increase in voltage or amperes. I think high current amps are the simpler build decision based on our inputs ability.

What would it take to have a high current through a high resistance...increased voltage.
What would it take to have a high current through a short circuit...transistors that can take the heat?
Edit: ChrisB already said it...oops.


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## ChrisB (Jul 3, 2008)

wheelieking71 said:


> but the title of the thread is "high voltage better than high current". better for what? are we talking SPL? or "sound quality".


Ahh, the ye old conundrum. When I first re-entered this hobby in 2007/2008 after the death of my first wife, I was led to believe that old school, high voltage amplifiers were the way to go and nothing made at the time could compare. Instead of retyping all my issues with old school gear, let's just say that it did NOT work out and leave it at that.

Regardless, it's all water under the bridge since I have since moved on to the more efficient, full range Class D JL Audio HD900/5. While I liked my old Lunar on highs with a Clarion DPX1851 on lows setup, it took up too much trunk space. 

For those who insist that old school, high voltage is where it is at... Please feel free to continue believing that a trunk full of amplifiers and near single digit efficiencies are the way to go with all the technology available today!

I'm done with this thread unless Cablguy184 wants to explain how placing first by default at the local comps (sometimes not even being judged) then finishing dead last at world finals makes him an authority on DIY car audio. After all, he did hint that he was better than me because he competed in USACi.


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## wheelieking71 (Dec 20, 2006)

dont take my comments as preaching high power is best. quite the contrary actually. im just stating there is no one amp that is "best" for every situation. i have used a few full-range class-D amps, and did not care for them. they seemed very one-dimensional, and lacked realism. but its been a couple years, and i know technology keeps marching on. the new JL stuff might sound killer. but untill i can buy a nice used amp for $150, im out. the cost is rediculous. i have less than $2000 invested in 40channels of old-school laying around that i know sounds better than any speakers i could possibly afford. and there is a good chance that it sounds better than that brand new HD. im all for the "small amp movement"! but i am NOT for the cost. it would cost me $10k to cut the physical size of my amps in half and come close to maintaining the potential sonics of my amps. i like the versatility of having lots of options at my disposal in case i want to try something new. if i decide i want to try a center channel, i can just grab a $50-100 amp off the shelf. not a $300-400 amp off the shelf. for people who can afford it, i say hell yea! the difference between that HD, and my ADCOM becomes inaudible on the freeway at 65mph anyway. again, just reinforcing that there is no one best brand, topology, or style of amp for every single situation. different vehicles, music styles, install priorities, and even hobbyists will all dictate different amp choices. for some just owning the equipment is part of the fun of the hobby. i like ADCOM amps. are they the best amps ever? NO, but i like em. after all, if it was only about the music we wouldnt be listening in an automobile. but bass sure is fun in a car! (and i consider myself an essque guy LOL)


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