Ditching Class A Amps due to Heat - Sort of a Poll


A discussion elsewhere about the future of Class A made me wonder how true one statement really is. So the questions are...

Have you done away with your Class A Amp due to Heat concerns?

Will you be moving away from Class A Amp due to Heat concerns?

Will you never buy a Class A Amp due to Heat concerns?

I only have a class A/B unit that does Class A up to 6 watts with almost no heat so really can't speak for those who have used in the past or currently own and run Class A Amps.

brianh61

@clearthinker

Sorr @axo1989 New Krells are NOT pure Class A. So called anticipator circuits don’t work So called plateau bias doesn’t work. No short cut to good sound. No free lunch.

I didn’t mention new Krell, Evolution series are D’Agostino designs (even though the e-series appeared after he and Rondi were forced out). And sustained plateau bias (and active cascoding) works—obviously—in the sense that it does what it’s designed to do, prevent notch distortion (the basic reason we want Class A) while reducing power consumption.

But if you want to argue that isn’t pure Class A, fair enough. I can change my answers to no, no and yes, respectively. Unless I change to high efficiency speakers and a low powered amp (and accept the tedium of constantly switching the damn thing off and on again) I’d steer clear of old-school Class A.

But while you're there, and since you are obviously into it, do you think the really old Krells sound better than the ones I have in mind?

PS: I did look longingly at the KAS pair that a guy in Melbourne advertises from time to time. Beautiful. Logistics though. Re your amps, KRS 200 was the original Class A version and the S was their sustained plateau bias model, yes?

Really, this is a thing? I've been running Class A for years and it really hasn't had any noticeable impact on my home energy consumption over other amp classes or tubes. I'm currently run a Pioneer M22 which is 30wpc pure Class A and it would take a heck of a lot for me to move away from it. Each to their own though.