At the clipping point, two amps have to have sensibly the same supply voltage, and current delivery. I do not see how this prevents amp A from having a smaller wire size and higher idle voltage.
Originally Posted by PENG
The higher voltage is the sum of the voltage loss in the secondary AND voltage supplied to the amp. These two voltages added give the idle voltage.
Again, to be clear, you can't rely on a higher voltage if you are keeping the impedance (resistance in this example) the same for both amps because P=I²R, or V²/R. As long as P and R are the same, V and I must be the same.
As you start drawing current, you start having voltage drop within the primary/secondary due to their internal resistance. The two V that are the same that you mention are the V delivered to the amp, of course they are, a watt is a watt. But at clipping, the weaker transformer wastes power in its secondary and its primary in the form of heat, because for the same I and higher internal resistances, then:
Power loss = VI = (Vidle - Vclipping) * I
The more difference between Vidle and Vclipping, the more power loss in the transformer for the same power delivery to the speakers.
I hope this logic looks a bit less circular now.
Denon 3808CI, HK Citation 5.1 Amp (replaces Denon for front channels), Panasonic 50" Plasma, SONY BDP-37 Player, GoFlex Media Player, Missions for Center, 4x12" home made for subs, Celestion Ditton 25 for fronts, in-wall Good Enough in the back.
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