Competitive class D amp suggestions

@mglik, the Berning Quadrature Z are $33k list. I'm not one of those people that feels the higher the cost the better the sound. While the Berning amps are quite good, and I respect David Berning as an innovative audio engineer, I'd never pay $33k for them. Too much out there at a fraction of the cost that is a better value in my opinion. So yes, the Atma-Sphere Class D were right there with them, so much so that I packed the Berning Quadratures up today to get them ready for sale, to be followed by the Atma-Sphere M-60s. I am keeping the Atma-Sphere Class D, as well as my Music Reference OTL-1, RM-10, and RM-9 SE amps.

I've known Ralph for a while and have been an Atma-Sphere customer for some time owning an MP-3 preamp and M-60 OTLs. I have had the Class D amps in my system now for about 6 weeks. In the simplest of terms I will say they made the OTLs obsolete. On top of that I have lent them to 2 people and both of them placed an order after their listening comparisons.

I have Bel Canto REF1000 MkIIs and while I think they are a very good Class D amp, I prefer the Atma-Sphere. In my opinion they have all the attributes of a tube amp with the transparency and speed of an OTL, as well as no heat to deal with and they are much more power consumption friendly. In comparison to the LSA, the LSA came off grainy in the upper frequencies, it was clearly heard after listening to the Atma-Sphere amps.

@niodari first I will say at it's price point, especially if it was purchased with the introductory discount, the LSA amp is a good value. There is a lot to like about it. However, the upper frequencies did exhibit some distortion, it's overall balance is inconsistent as a result. For example, trumpet would start to sound a bit harsh and grainy, almost aggressive and lacking smoothness in comparison to the Atma-Sphere amps. You can hear this on drum cymbals as well, especially in more complex passages. The violin loses some of it's natural tone. The Atma-Sphere, like a well designed OTL, which Ralph manufactures as well, doesn't exhibit this level of distortion. It is a very smooth and balanced presentation. If you go back and re-read his post above he provides the answer to this very clearly.

@niodari, other than the Class D amps I previously mentioned, as well as the Merrill amps, I have no other listening experiences I can share. I will say this, it is worth paying attention to some of the unique design aspects of the Atma-Sphere amps when compared to other GaN amps. As Ralph spoke to in his post they eliminate what is wrong with solid state amps in general (and too an extent tube amps as well), not just GaN amps. As a tube amp designer it was a revelation to him, and he has been doing this for nearly half a century.

Nelson Pass is correct about the 2nd harmonic, great for simple music, but not for complex music. Here is a quote from the late Roger Modjeski on the topic as well:

"Once again, I remind people that 2^nd harmonic is not benign on complex music, i.e. anything more than a solo. What people are missing is that large 2^nd harmonic distortion also means there is large IMD and here I'm talking of the good old SMPTE test, 60Hz and 6kHz mixed at 4:1. The nice treble note riding on the 60Hz bass gets crushed in the valley of the 2^nd harmonic wave. Doesn't anyone think about this? It's so obvious and easy to hear."

I have read a number of times where Ralph talks about 2nd and 3rd harmonics being pleasing to the ear, and where higher ordered harmonics are not. I have his Class D amplifiers and also his M60 monoblocks, as well as a Music Reference OTL and David Berning Quadrature ZOTL amps. The Atma-Sphere Class D is right there with all of them. In fact I have said to Ralph and a number of people who I have had listen to the Class D amps that they in some ways make the OTLs sound obsolete. There is some really cool things that Ralph is doing in his circuit that other Class D manufacturers are not, and it's evident in the sound.

Don't be concerned if Ralph does not pop in here. He is off on a month long bicycle trip riding along the Continental Divide. So his access to the Internet as well as time to respond on this thread may be limited.

@ghdprentice, maybe I should have stated my point a different way. I know too many people who when doing comparisons think along the lines of, "Well it cost $100,000 so it must be better...". To your point, I do go for value, but I go for the highest quality of sound I can attain as well. In addition to moderately priced components I have some very expensive components in my system. All components in my system were chosen for their value, regardless of their price, and because they contribute to the overall enjoyment of my system.