What could I expect to hear from a Class A amp?

Shadorne - I suspect that ferrofluid used in many tweeters changes viscosity with temperature.

Shadorne -- Excellent thoughts, as usual, which are not commonly realized. Thanks!

I'm not sure I understand, though, why Class A would run cooler when outputting signal into a load. It's tempting to think that could result from a portion of the current that would otherwise flow through some of the output transistors (at zero signal conditions), being diverted through the speaker instead. But I don't think that would happen to any significant degree in the typical situation where the amp's output impedance is much less than the speaker's impedance, so that the amp behaves essentially like a voltage source.

In any event, it seems clear that the presence of signal would not raise the operating temperatures significantly above what they are at idle.

Thanks again!

-- Al

Kijanki, this waiting does happen during the day, on the weekend as well. You are correct about me being picky. Yet it seems that if I want to get the typical benefit of class A, I'll have to wait. Otherwise it sounds closer to my former class AB amplifier which is not bad really.

I use a class a amp with 88db 4ohm speakers and it is definately worth it imho. My experience is that it takes 45 minutes to warm up with improvements up to 4 hours. I leave the amp in "standby" mode and never turn it off. Standby does not generate heat but keeps enough current that it doesn't experience a cold start. It generates 150W into 8 ohms 300W into 4 ohms and 600W into 2ohms. It will play ear crushingly loud. Compared to ab amps I've had it has more low level detail and never shows a hint of strain even with the minimum impedance of 2.5 ohms on my speakers. With any given setup any given individual may prefer a different set up and few generalizations can be made. My personal belief is that properly executed ss amps with large power supplies capable of doubling down far more than their ab counterparts with much smaller power supplies are ideal for high impedance loads with reasonable sensitivity. - jim

Hey, I already said, the XA-100.5 monos did 115 dB without ever choking up on
any dynamic swing, and the X-600.5 never gassed out on heavy bass runs. The
needle never moved, staying class A. It blows your hair back, and to think they
are working a 1 ohm load throughout. The long ribbons never get warm.