Originally Posted by ChrisW66
The power dissipation in any class A amplifier is constant, whether Quiescent or at Full power. So the power draw from the mains is constant.
I don't believe this to be true and it goes against everything I've learned. A class A amp, at its simplest, is a single transistor with a base (which is the input to be amplified), a collector (which is the power supply), and an emitter (the output). The higher the current that flows from the base, the proportionately greater the number of electrons allowed to flow from the collector to the emitter. Ergo: the power draw has to be proportional to the music being played.

In a class A amp, there is always a positive bias to the base, which means there is always power being drawn (and heat generated), but not the same amount regardless of the volume or the music being played.

Prolific music listener / Hi-Fi addict!