Class D Amp For 'Stats?

Never mind Distephenson. Either he has limited experience with this new genre, or an inhospitable system hindering their proper function.

See my system review, at:

http://forum.audiogon.com/cgi-bin/fr.pl?vaslt&1133363314&read&3&4&

I have a Bel Canto evo-4 and, it sounds outstanding on my Magnepan 3.6's. My favorite amplifier on these speakers. However, I do not like it on Sound Lab U2's as the sound character is thin and bright'ish. Switching amplifiers have an output filter and, this filter will interact to some degree with the load impedance. With Sound Labs, the reactive load impedance varies quite a lot especially in the lower registers. The BC just does not seem happy with the SLs. It's speculation, but I suspect it's not much different with any switching amplifier as they all have have an LC output filter.

The Atmasphere OTL amplifiers are my favorite on the big SL's - the MA-1s and MA-2s in particular. I have spent considerable time with both and, both work great. I have also tried the Wolcott 220s and, the Innersound ESL-300. There is a palpable richness with the Atmasphere's that manage to elude the other amps.

The Innersound ESL amps were designed to drive the capacitive load of electrostatics. They will do so while sounding outstanding and without strain. An electrostatic speaker is a capacitive load which is very difficult for most amps.

I too have the SL A1's. Earlier this year I tried the H20 non-signature stereo amp here. Once I got passed the claimed "inapplicability" of these amps with MIT ICs, I had pretty much the same results with NBS ICs....the H20 was fine but not a musical match with the A1s. Resolving, yes......involving it simply was not. An older Counterpoint NPS400 had far more portrayal of space and body even though it lacked the ultimate extension at the frequency extremes. The CAT JL-3 Signature amps took the musicality so far beyond the H20, but of course at a price. The CAT's dynamics and incredible resolution brings out these same strengths of the SL's.

I have also heard the JL-2 with the SL speakers and for the price, it is unbeatable. This on the used market is not too much different from a pair of the fully decked out H20 mono amps and the JL-2 would simply destroy the H20's with the SLs.

And Nealhood brings up another great option with the Atmaspheres. I also heard the MA1's with the SL's and these too are incredibly musical with a more rich and full lower midrange but not quite the dynamics and ultimate resolution of the CAT JL-2. This was a back-to-back comparison of the SL U1's last year.

As for Brystons, before I had the A1's, I had the Magnepan 3.3 and 3.5 for 6 years. Several amps that I owned, ARC VT130, Wolcott 220, even the Counterpoint NPS400 hybrid drove the Magnepans to a musical level the Brystons simply could not touch. Speaker drivability is only part of the equation. Why anyone would use the Bryston amps with Maggies is beyond me and yet that is often what you read about with these speakers. And to consider them on the much more dynamic and resolving SL speakers makes no sense at all.

Dlstephenson,

Can you tell me what amps you have heard? What you seem to be describing is quite different to my own experiences. thanks.