# Power Ratings of Amplifiers



## humandrummachine (May 17, 2010)

Hello everyone,

What's the deal with the power ratings of some amplifiers out there today? For example, look at these two amps from Sonicelectronix:

Boss CHD3000 - $109.99 - claims *750*Wrms x 1 @ 4 ohm

Alpine MRV-M250 - $109.99 - claims *150*Wrms x 1 @ 4 ohm

Same price but there is a 600Wrms difference in power rating. Seems like way too extreme of a margin. I definitely know that some brands inflate power ratings, however, I am also open to the possibility of some products being overpriced. Is the power rating system being abused that badly, and if so, how can they get away with it?


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## rton20s (Feb 14, 2011)

Are you trolling right now?

The answer is obvious to anyone who takes even a couple minutes to search. One of those ratings is from a reputable company and likely accurate and slightly conservative. The other is from a company which isn't quite a reputable and is known for highly exaggerating the capabilities of their equipment. I'll let you figure out which might be which. 

For the closest thing to an apples:apples comparison, look for amps that are CEA-2006 compliant.


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## SkizeR (Apr 19, 2011)

rton20s said:


> For the closest thing to an apples:apples comparison, look for amps that are CEA-2006 compliant.


even this doesnt mean much noiw a days. ive seen some well overrated amps that are supposedly cea 2006 compliant


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## rton20s (Feb 14, 2011)

SkizeR said:


> even this doesnt mean much noiw a days. ive seen some well overrated amps that are supposedly cea 2006 compliant


Agreed. 



rton20s said:


> For the *closest* thing to an apples:apples comparison, look for amps that are CEA-2006 compliant.


Just buy a quality amp from a reputable brand and call it a day.


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## 350al (Jan 14, 2016)

rton20s said:


> Agreed.
> 
> 
> 
> Just buy a quality amp from a reputable brand and call it a day.



I guess some people just getting into the hobby don't know the difference between a reputable company and an overrated company...


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## PorkCereal (Nov 24, 2009)

Companies throw big max settings the amp could potentially hit for a brief moment. It's to get uninformed people to see high numbers and want to buy them. Mass marketing to sheeple. 

Sent from my SAMSUNG-SM-G935A using Tapatalk


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## 350al (Jan 14, 2016)

PorkCereal said:


> Companies throw big max settings the amp could potentially hit for a brief moment. It's to get uninformed people to see high numbers and want to buy them. Mass marketing to sheeple.
> 
> Sent from my SAMSUNG-SM-G935A using Tapatalk


I lost a sale a few weeks ago because my sub's peak was 600 and the other sub the guy was looking at was 200rms 1200 peak or something like that.. Because peak is the most important number apparently :mean:


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## rton20s (Feb 14, 2011)

350al said:


> I guess some people just getting into the hobby don't know the difference between a reputable company and an overrated company...


That may be the case. But the OP has been a member of this forum for almost 6 years and has over 400 posts.


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## firebirdude (Dec 24, 2009)

The CEA2006 standard is the closet thing you're going to get if you're trying to compare power ratings between companies. But even that has some wiggle room for deception in it where the company can still legally display the CEA logo. Example, the CEA requirement says that the power numbers acheived at the standard they have set must be displayed in their little box. However.... the CEA standard then goes on to specifically say that anything outside of their little box is fair game. So you can put 200W in their little 2"x1" box and still print 800W in 200pt font all over the box.

And then you have companies that all-out try to rip off the logo. It'll have the same light blue circle with a small symbol of two diodes inside or something very similar. And then it'll say "Electronics Standard Certified" or something around the outside, like the CEA2006 symbol. So it's very similar to the CEA2006 symbol, but just different enough to not legally be the same.


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## Victor_inox (Apr 27, 2012)

350al said:


> I guess some people just getting into the hobby don't know the difference between a reputable company and an overrated company...


some people? most of them!


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## humandrummachine (May 17, 2010)

rton20s said:


> Are you trolling right now?
> 
> The answer is obvious to anyone who takes even a couple minutes to search. One of those ratings is from a reputable company and likely accurate and slightly conservative. The other is from a company which isn't quite a reputable and is known for highly exaggerating the capabilities of their equipment. I'll let you figure out which might be which.
> 
> For the closest thing to an apples:apples comparison, look for amps that are CEA-2006 compliant.


I'll give it to you the Alpine vs. Boss comparison shouldn't have been made... I'm more interested in what is sacrificed in cheaper amps that claim high power ratings. Let me run another comparison off of you:

Audiopipe APCL-30001D - $359.99 - claims 3000Wrms @ 2 ohm

JL Audio XD1000/1v2 - $599.95 - claims 1000Wrms @ 2 ohm

Reading online, people say that the Audiopipe amp isn't that bad. Some say it won't quite do the rated power, but close. I know there might not be much you can say for sound quality because these amps are made for subs, *but what is sacrificed between these amps? Efficiency? Reliablility? Some sound quality?* The JL is much smaller but also rated at 1/3 the power.

Honestly I really like the look of the Audiopipe amp. I'm wondering that since it is rated for so much more power, could I run it at a higher impedance, like 8 ohm, and retain most of the benefits the JL amp might have over it? From other diyma threads, it seems like this could be true.


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## Viggen (May 2, 2011)

Yes I would say efficiency, sq and reliability is all sacrificed with the cheap stuff

They also inflate numbers posting max power and/or max power at a low ohm load

And people fall for it all the time


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## firebirdude (Dec 24, 2009)

One important spec that's often overlooked on CEA rated amps is <1% THD. So if the 3000W Audiopipe actually does 2300W, it's likely WELL over 1% THD. But power aside, yes, reliability/protection modes are huge. It's no thing for a cheap cap to blow up and render your amp useless. It's no thing for you to accidentally short two speaker leads together and fry the amp (instead of going into protection). All that said, yeah, of course there's flat-out some better dollar/watt ratios out there than JL (or whatever).

And if you think that gaudy Audiopipe looks better than the JL.... I suggest you see it in person before you buy. If you still like it better, ask the dealer how much for spinner rims and neon too.


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## Weigel21 (Sep 8, 2014)

Some Audiopipe amps have been dyno'd and actually did quite well. The dyno only measures power output up to 1%THD. Don't think the model specified above is one of them though.


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## Kelocyde (Oct 29, 2012)

I'm gonna throw this out here and everyone will hate me:
All amps sound the same, they just distort differently.

Now that being said, it will be taken heavily out of context.
You can achieve 6wpc tube amp with 10% distortion, but the even-order distortion it produces is more pleasing(or less to some), for example. Now lets go back to trusting your ears cause science can't quite explain personal preference: I like strawberries, you might like bananas..

Audiopipe was notorious for making rated power, but needing a strong electrical system to do so (efficiency.) They still make power (obviously per dynos and hundreds of anecdotal clamps) and do it much easier now..probably due to the market driving the demand. 

I wish I could find the test or software to add distortion, but I doubt most individuals could distinguish .1% THD from 1% THD. 5-10% would be very noticeable.

Flame me, kgo!


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## rton20s (Feb 14, 2011)

Kelocyde said:


> I'm gonna throw this out here and everyone will hate me:
> All amps sound the same, they just distort differently.


I believe this is the thread you are looking for... 
http://www.diymobileaudio.com/forum/car-audio-truth-myths-industry-dogma/141216-higher-end-amp-sq-myth.html


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## oddfuturemang (May 15, 2016)

Boss is very walmart brand, I could see them definitely inflating the number


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## annoyingrob (Aug 24, 2007)

humandrummachine said:


> Is the power rating system being abused that badly, and if so, how can they get away with it?


Before CEA-2006, there wasn't a "standard" way of measuring power. There were commonly used measurement practices, but manufacturers were free to measure power as they see fit. Even now with CEA-2006 manufacturers are STILL free to measure power how they see fit. There also isn't any form of governing body monitoring their ratings to ensure they advertise match standard measurement practises.



> The CEA isn’t the Federal Trade Commission and can’t compel amplifier manufacturers to adhere to the spec. CEA 2006 isn’t the law, it’s just a good idea and was designed to help customers make an informed decision about the amplifiers they'll spend their hard-earned money on. Look for the CEA 2006- compliant spec on the amplifier’s box to be sure you’re getting all the power you’re paying for. Only you can compel amplifier manufacturers to adhere to the new rating standard.



There are tons of different ways that you can "game the system" to to speak
- What voltage do I measure the amp at? 12v? 14v? 16v?
- What's my load impedance for measurement? 2ohm, 4oh, 8ohm? Do I just measure it at 16 ohms and multiply the result by 4 to get a "4 ohm" power output because I "Dont have a 4ohm load lying around"
- Is my load purely resistive, or highly reactive? (IE: does it just dissipate energy, or does is store energy in some form to dissipate later in time, like a coil of wire storing energy in a magnatic field) 
- Over what time period am I measuring? Do I measure power output for a microsecond, or over several minutes?
- Do I measure the average or peak? What's the sample rate of my measurement equipment? Capturing a million samples per second is going to pick up a much higher instantaneous peak than a thousand samples per second on a very fast burst output.
- How do I cool the amplifier? What's the ambient temperature? Do I have the amp sitting in a trunk in a car in an 80F warehouse, or am I measuring it outside in the -40F Canadian winter? Am I blowing fans on it?
- Am I measuring one channel loaded, or all channels loaded?
- At what amount of distortion to I consider the upper bound for my test? If I can produce 100w at 1% THD, I can likely produce 200w at 100% THD.

All of these will affect the ratings. The thing is, none of these measurement differences are necessarily WRONG, they're just different. If I know how to manipulate these to give "bigger" numbers, and I feel that that will sell my product, I might do that. Company X might say " I feel this is the best way to measure power", and company Y might think a completely different way of measurement is the correct way of measuring power.

Even after all of that, some manufacturers will still just make up numbers, nobody is going to necessarily stop them. Claims of "False advertising" will probably fall away in court with "You're not measuring power like we measured power". Wasn't there a quote from Zed audio when they made some amps for Boss, Stephen Mantz said "This amp makes x power", Boss took that number and doubled it.



It's a lot like measuring horsepower. You can't compare the power results of a Dynojet compared to a Dyno Dynamics. Even measurements on the same equipment can't reliably be compared between cities or even the same city on different days (granted Dynojet "standardizes" their results to compensate for these variations). Different companies measure power differently, and it's difficult to compare between them. CEA-2006 attempts to set out a set of standards to compare apples to apples but even then it's not 100%. I had my car measure 100hp different on two different dynos with the same tune.


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## Victor_inox (Apr 27, 2012)

Yeah but unlike measuring horsepower there is no variations in air density, elevation, temperature,etc. measuring amplifier power is plain and simple.
Many manufacturers today specify that power should not be measured on resistive load like drop a big ass resistor in there and feed 100Hz sine wave. 
most modern amplifiers power supplies will meltdown on such test.


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## Jepalan (Jun 27, 2013)

I like the way consumer vacuum cleaners are rated by the amount of current they draw from the mains power (6-amp, 10-amp, 12-amp, etc). 

Completely nebulous. No defined relationship to the amount of suction at all. 

Maybe we should rate amplifiers by how much they weigh?


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## firebirdude (Dec 24, 2009)

Jepalan said:


> Maybe we should rate amplifiers by how much they weigh?


Might be more beneficial actually..... :laugh:


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## rton20s (Feb 14, 2011)

firebirdude said:


> Might be more beneficial actually..... :laugh:


The way some people hoard gear, this could be good information to have. You'll want to make sure you don't exceed the load capacity of your attic joists.


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## firebirdude (Dec 24, 2009)




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