What do you think of Class D amplifiers?

Heard the Class D offering fom Bel Canto pair with Thiel sometime ago and simply not impressed. Have heard other class D amp as well. Same result FAIL. Just find something is not right with the sound.

I used to be a total sceptic, in the past I had built some small ones for use in the school physics department, ok for driving various transducers but not great sounding.  I recently have heard some behemoths built using these modules.  Link: http://www.hypex.nl/  I can think of only superlatives, bass control like none other, smooth, unlimited dynamic range and everything that class D was not supposed to do properly. In all, stunning! But of course you have to build your own...

That is interesting. Could be that I have listened to the Bel Canto in a very good tuned set-up. But for the rest I totaly agree with you. There is something artificial about the sound.

The best power amp I've ever heard at home for a week was Primare's fairly new A34.2. Allegedly better than the Bel Cantos by a big margin but costs £2100 according to a delear that sells both.

Added:

The sound was noticeably clean - reminded me of class A but using a lot less power.

I mostly don't get on with Class D, but just as you've found, Bel Canto has been the best of what I've heard.....I still wouldn't give up Class A for it though.

The biggest problem that I have with all the Class D amps that I've heard, including a Bel Canto Evo is what they do to piano music. It's hard to describe, but pianos don't sound like pianos.

If I might put in a good word for the Class D amp at the heart of my own system. (Albeit contained within a £479 'all-in-one' unit.)

Short of Rega launching an 'all-in-one' (or me winning a sizeable lottery pay-out and going bonkers at my nearest Luxman/Harbeth vendors), I have no desire to change or upgrade from the M-CR603.

After hearing how clean and noiseless my old Pioneer SCLX82 and 83 sounded with music, I stuck to Class D when I upgraded to a pre-power. For budget purposes, I went for the Rotel RMB1575. 

I feel that Class D sounds more neutral than Class A/B, and the resulting sound is dependent on the source and system as a whole. Since changing my pre-processor to the Audiolab 8200AP, my system has improved greatly for music. While power amplification is important, the pre-amplifier is even more important, and can make or break a system. There aren't that many high quality pre-amplifiers around, and I feel that it is the pre-amplifier that governs how good any power amplifier can ultimately sound.

I'm loving mine, and Class D will certainly be at the top of the list when I eventually come to upgrade. Although, i can't help liking Bryston and a certain other brand...

I agree on this with you Frank. The more you go 'high-end' the more important the pre-amplifier becomes. Until now I am not convinced with the Class D amps. It sounds very clean and neutral, but there is some area what I would call the 'X-factor' that it just doesn't have for me.

Can't say I've ever heard a Class D amp, although I have seen the odd review of them.

By the way, why D? What happened to Class C?

Class C is not really suitable for audio. It is used for high frequency modules.

Whilst class D are not exactly new, semiconductor technology steadily evolves. Although earlier examples have been reported as sounding objectionable, they are (or some are) becoming very good. My money is on class D taking over from class A/B where gains in efficiency will drive the concept & class A will continue for those without more conventional forms of room heating! Ironically, well implemented class D sound similar to class A anyway & will appeal to those with central heating.

Many thanks, Ocean37, for easing my ignorance a little.

Aren't most car stereos class D? A car has small space to offer which should not build up heat and limited power.

I'm very happy with the class D amplification in my RZ-1, but I haven't compared it to other class d amps.

Then again, I bought an all in one unit because I was prepared to compromise in space, so I don't think I'd be too upset at the compromises brought by class d. TBH, I think the quality of the sound is as good a comparably priced Marantz separates that I was considering at the time.