There is one missing element.
That is that the power supply has a timing constant. That is to say, there is a certain time period that will elapse if the power transformer is unplugged, where the voltage will sag to a certain point while the supply is under load.
Then there is a timing constant in the amplifier itself. This is the -3db point of the amplifier.
If the amplifier has a -3 db point that is a frequency lower than that of the timing constant of the power supply, then the amplifier can modulate the supply, which results in IM distortion amongst other things.
This is why an amplifier should never be direct-coupled from input to output! Otherwise, the amount of capacitance needed to get the timing constant of the supply low enough goes towards infinity.
This is why an amplifier can 'motorboat' (repeated thump) if a filter capacitor fails in the supply- the timing constant has become so high that the amplifier exhibits low frequency instability.
I apologize if I went a little too esoteric here, but there is obviously more to it than just inrush currents and the like. If something is not clear let me know.
That is that the power supply has a timing constant. That is to say, there is a certain time period that will elapse if the power transformer is unplugged, where the voltage will sag to a certain point while the supply is under load.
Then there is a timing constant in the amplifier itself. This is the -3db point of the amplifier.
If the amplifier has a -3 db point that is a frequency lower than that of the timing constant of the power supply, then the amplifier can modulate the supply, which results in IM distortion amongst other things.
This is why an amplifier should never be direct-coupled from input to output! Otherwise, the amount of capacitance needed to get the timing constant of the supply low enough goes towards infinity.
This is why an amplifier can 'motorboat' (repeated thump) if a filter capacitor fails in the supply- the timing constant has become so high that the amplifier exhibits low frequency instability.
I apologize if I went a little too esoteric here, but there is obviously more to it than just inrush currents and the like. If something is not clear let me know.