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Audio Systems/various class power amplifier efficiency


hi, i want to ask that "A" class audio amplifier 25% efficient, class "B" is 50% efficient, class "C", "D", and "F" are 90% efficient.
my question is as under.
1 - what is the meaning of various class efficiency and efficiency has to do with what
   (A) - more efficient audio power amplifier give more out put at speaker? or vice a versa.
   (B) - more efficient audio power amplifier draw less ac watt at      electricity supply? or vice a versa.
   (C) - class "H" and "G" audio power amplifier how much efficient?


There is a very good discussion in this paper:

I suggest you begin reading around page 16.

Class H and G require a feedback to the power supply increasing the rail voltages as the power out increases. It is just a variation of circuitry to get a little more efficiency.  This class of audio power amplifier has not become popular because the benefits do not offset the additional cost of the complex circuitry.

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Audio Design Engineer; systems, loudspeakers, cd/dvd players, etc. I am knowledgeable in all high end audio equipment and installations. MAKE SURE YOU GIVE A MAKE AND MODEL NUMBER AND CAR IF IT IS AN AUTO QUESTION. Note: I am getting some who ask good questions that take a lot of time to research but then the questioner fails to read the answer. Please don't ask questions unless you are seriously looking for an answer. If you find an answer to your question otherwise then let me know with your reply. Thank you.


Have been associated with audio design, standards, testing and component systems for over 40 years.

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