03-02-12: :Manitunc. Those amps don't use as much power when idling and don't get quite as not. My Dussun V6i, Musical Fidelity M3, Nobis Convigore and Classe 100 all run that way and sound pretty good. Manitunc:
If they don't run hot then they are not biased very high into Class A, maybe just a few watts depending on heatsink area.
"Ohms Law" simply put for the non technical to understand,
A 25 watt "only" pure class A biased amp needs X amount of heatsink area as the ML2's have I posted the link to.
A 100-150watt class a/b amp with 25watts of pure Class A bias needs up to 4 x the amount of heatsink area, even though the class A is the same as the ML2's, because the rail voltages are so much higher for the extra a/b watts, this quadruples the heat, even though it's still only 25 watts Class A.
Then there's the sliding (Plateau Biasing) Class A amps like Krell developed, but they were never as good sounding as their Pure Class A classics, like the old KSA50 KSA80 and KSA100 monoblocks all with fan forced cooling with no external heatsinks, just chimney's inside with fans at the bottom.
Cheers George