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In reading a review of a semi high end multi channel amplifier it was stated the amplifier has an "800va toridal" power transformer. That's 800 watts if your power factor is unity. The specs of the unit which were published in the artical as well stated "105 watts RMS per channel with seven channels driven" That's 735 RMS watts of audio power.


Well folks, those with any amplifier design expereince knows that can't happen. Class AB circuits run max of 60% efficiency. Class A is far worse. There are some designs such as class D which is a switch mode amplifier that can run up to 95% efficiency but this was not such a design. Class C amplification does not work for audio and higher classes are just Japaniese variations of the basic ABCD and still not much better than 60% efficiency.


This is not the first time I have seen these multi channel amps rated this way. It's mis-leading and perhaps fraud. I think they are rating the RMS power for any TWO channels at once. Granted a 5.1 sound track would not typically need all channels driven at once to equal levels, the specs are none the less impossible. Far worse are the lower end 5.1 receivers but at the
 

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Glimmie, I don't pretend to be a technical expert - anyone who knows me knows I'm not.;) ;)


But sounds like you've done your homework and the technical representations here are somewhat suspect.


[Moderator note: Please folks, as Moderator, I don't mind use of the term "misrepresentation" or even "questionably representation" when you have some facts to back it up, as Glimmie does. But please, no more comments on "fraud", as that is a legal term of art which is much more serious contexually and thus forum rules do ask we refrain from using that term. Thanks for understanding.]
 
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