Competitive class D amp suggestions

Ralph, thank you for the explanation. One thing I’m still not clear about is why people describe class a and high bias a/b as being warm sounding especially if their overall distortion is on the higher side?

Nord Acoustics NC500 MKII Dual Mono

Amazing Amp, my new favorite. I like it better than my PS Audio M700s and/or BHK 300.

One thing I’m still not clear about is why people describe class a and high bias a/b as being warm sounding especially if their overall distortion is on the higher side?

The distortion can be quite low! The tricky bit is knowing what is meant by 'warm'; to some this is a bit of extra mid bass energy. I see it as 2nd harmonic and of course it can be both. I think you'll find though if you delve deeper that those comments do not apply to all. Nelson Pass is aware of how distortion affects tonality so he is careful in his designs to make sure he's got a bit of 2nd going on to help out in that regard.

I have a small update on the LSA GaN 360 Voyager amp. it should have now a bit over 100 hours of burn-in (I used it more than usually in my second system basically leaving it on most of time). I did not note any essential improvements after 80 hours or so. Perhaps, it may still get a bit better. 

I can say now how the Voyager compares with the Cherry Megaschino  in my second system. The sound of Cherry is cleaner, more open, less "forced" and more alive and natural (even with half-working right channel, I  adjust the channels taking an extreme balance position). 

To me,  Cherry  does not sound like a traditional class D amp, while Voyager sounds like a good class D amp, perhaps the best one I have heard  so far except Cherry. No doubt that it is a very good value performance/price. 

I suggest that Atmosphere and AGD  amps may sound somewhat similar to Cherry, but cannot be sure of course. For me, Cherry just sounds like a good class A tube amp, point. So pity that Tommy passed away!

Soon I will move the Voyager to my main system. I will let you know about my impressions in a few days or so. 

@twoleftears and ​​​​@atmasphere , thanks for additional explications! I did not reilase, from the beginning, that different pics were different harmonics, a very useful image. But now I do not understand what the blue curve stands for. 

@niodari Red and blue track the two stereo channels.  In a well engineered component, they should pretty much overlay; more than a little divergence is indicative of a problem with components, construction, design, etc.