power consumption vs RMS rating of amps

[vu2oro]

Hi, that's exactly what I said, if a stereo power amp consumes x watts, total undistorted output (by undistorted I mean THD <0.05-0.1%) can never be more than about 0.3x per channel. Considering about 60% efficiency for class AB! Beyond that the power transistors will start saturating due to that thing called Vce(sat) for the more technically oriented, because there is no more power supply headroom and the amplified signal starts to flat top, or clip : one of the major contributor to THD figures.

 

[vu2oro]

Just another thing: somebody stated "class B" printed on the rear panel: that has more to do with the EMI/EMC compliance standards, I believe, than the "class" of operation. Hi Fi aud amps will typically be class AB1 or AB2,(if not class A or class D/G/H): not pure class B, because pure class B introduces something called "crossover distortion" very annoying to the ear!!
Needless to mention, this "crossover" has nothing to do with the speaker crossovers ...Kindly google it if you feel its worth!