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I know that max doesnt mean diddly and that rms is the only important number but why is there a max number? It cant be just to a sales tactic. So why is there a max number and where does it come from?
 

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Mostly from marketing, because it can be a larger number.

Technically there can be a max number, but with music it just can't work. Music is dynamic and always changing, so how can one number ever be useful as a rating? At least RMS is more of an average rating that could relate to an average output of music. Since you are using these ratings to compare and size equipment for music reproduction, you really need to know how it works over time. So there can be a peak electrical number, but this is not an ignition coil its sound equipment. It is not useful.

You could say it is a tiny bit useful on a sub, because a sub will heat and impedance will rise...but we know that will happen over time. So a sub can burst to a higher power a long as power is reduced before it heats too much. Since music does that it gives you an idea how much it can handle for a moment over the average. Problem there is how do you measure that? How did they come to that figure? I have no idea. I like the way JL rates subs with the colors.
 

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Because the output of an amplifier is AC voltage and therefore can be expressed in RMS or Peak (which one they use is all about the marketing of the amplifier).

3 ways of expressing voltage of a common AC wave form

Scroll down and he says this,

Peak watts (misleading because many will take it as a true measure of the work that the amplifier will do when driving the speakers)
If the manufacturer specifies wattage as 'peak power' they may say that they aren't trying to mislead their customers, but I believe that that is precisely what they are trying to do. They assume that the vast majority of people are going to accept the wattage as the maximum power that the amplifier can produce. If they use peak voltage to derive the peak power, the power specification may be legitimate but it is misleading. The peak power is mathematically twice the RMS power output.
 

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The same reason why they change the packaging but not the ingredients. To get your attention and increase sales. Its B.S., basically. I always oversize my amps anyway. Its called headroom. :)
 

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Huh, you mean my 10,000W PMPO amp I got from Walmart for 79 dollars isn't going to get me 200 deebees? :(
 

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It's exactly for this reason that they started making the CES (CEA?) 2006 compliance standards. Those that adhere to this are allegedly stating the true power capabilities of their equipment in a way that is standardized across many different manufacturers. This way you can compare one company to another and know that their power measurement formula is the same.

I usually call these max. ratings "Imaginary Watts"
 

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It's exactly for this reason that they started making the CES (CEA?) 2006 compliance standards. Those that adhere to this are allegedly stating the true power capabilities of their equipment in a way that is standardized across many different manufacturers. This way you can compare one company to another and know that their power measurement formula is the same.

I usually call these max. ratings "Imaginary Watts"
Because most people are dumb enough to believe more = good....
Anyway, the CEA2006 also kinda misleading... Best still look at the power output at 12V, which is more accurate....
 

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Because the output of an amplifier is AC voltage and therefore can be expressed in RMS or Peak (which one they use is all about the marketing of the amplifier).

3 ways of expressing voltage of a common AC wave form

Scroll down and he says this,
best response EVA! it is a spec to get the noobs to believe they are getting more than they really are. take a look at what the THD is at that "max" rating. you will see what I mean, lol.
 

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The way I've always looked at it. they will never rate RMS at higher than 14.4 and my car does that all day for about 5 minutes a day. mostly hovers around 13.8. BUT back to my process. @14.4 or any voltage under 14.4 you'll have an RMS number of X and an WLS number of between 2x and 4x (4x is reserved for the most special of specials like BOSS).

The WLS rating is a very scientific term I've coined. When lightening strikes. It will produce that peak voltage WLS and only then. But it won't last.
 

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marketing.... most people would rather have a 1000w sony explode amp vs a 150w sony explode amp.... even though it's the same thing most people that buy that stuff like the big numbers.... others of us do not care

It would be nice if even RMS numbers were tested the same across all manufacturers, making those numbers more comparable.
 

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