Class D with high efficiency speakers

The Avantgarde Duos have self powered sub woofers so low bass performance of any amp will not be a factor. They are amongst the most revealing, most dynamic speakers ever made & until you actually listen to them properly set up with top quality ancillary equipment, most will not truly understand what they can do & how great they can be.

I powered mine for years w/ an Art Audio PX 25 tube power amp (5 watts / side) & it was truly magical at any volume. They will be a real test for a class D amp & any shortcomings it might have. I’m very curious to hear how that all turns out.. please keep us updated. Thanks

Thank you for th replies so far.

I've had the DUO's since 2007 and agree they need thorough set up and matching equipment. I found Jim Smith's book invaluable in getting my listening position and speaker position just right.

The AtmaSphere OTL's are a very good match (I've tried a number of amps) and I really like the sound I've been getting for the past 10 years+. But I've been intrigued by Ralph Karsten's views on Class D and the fact that he prefers his Class D amps to his own OTL's!

Ralph will know more about amplifiers and systems than I'll ever know so it was him that has set me off on this exploration!

I've also been in contact with another Avantgarde DUO owner who is using a NAD Class D amplifier very satisfactorily. 

I like trying things that are a bit different and I'll update this thread as I experiment.

I would not sell the OTL - wait until you’ve tried other types of amps, and give it time. I have Atma-sphere MA-1 v 3.2 monoblocs, mainly fed by the Io Eclipse. They are a daily joy in our system, with top level NOS driver and output tubes and clean power. I am on regular visits to my friends in our local audio circle, some of them with class D amps, but I always come back thinking that I love the tube OTL sound at home.

I was surprised that Ralph / Atma-sphere - post above - wrote that he didn’t miss it (M-60). I am sure his new class D sounds good. But I would guess it is a case of plus and minus?

I would certainly try it. It might make for a good match. 

I am sure his new class D sounds good. But I would guess it is a case of plus and minus?

@o_holter Its been a year and a half now and I've not heard any tradeoffs. But if your speakers are designed for amps with a high output impedance (and mine are, FWIW...) things might be different. If you are dealing with a speaker like that you might find the class D to be a bit leaner in the bass because it will make less energy into the impedance peaks that are in the bass region of the speaker.