Competitive class D amp suggestions

@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.

I have the AGD Tempo di Gan.  It's excellent.  I too would be curious to hear it pitted against Atmasphere's amps under controlled conditions, but there really isn't anything I want to improve at the moment, so that's not a priority.  Either it, or the Audio Envy Mega PC that I put on it, took a little while to break in, but then everything snapped into place.

Besides the ones I already mentioned, Jeff Rowland is another egregious omission.

Wow!  Obvious omissions here are the Orchard amps and AGD.

Orchard, AGD, and Atmasphere is the point where really interesting class D begins.

@niodari It's all about the implementation.  Asking that last question is like asking how different bipolars, jfets and mosfets sound.

Don't overlook this, too; there have been very good reports on its sonics.

https://www.dedicatedaudio.com/products/bel-canto-design-ref501s-stereo-amplifier

I'm kind of surprised there hasn't been more discussion of the Nuprime Evolution STA.  Anyone heard it?

I gather Jason Lim shut down production of the Evolution monoblocks because the Evolution STA offered 90-95% of the performance at just over half the price, so it is now their flagship product.  I can't seem to find out whether the STA uses proprietary modules or ones purchased from an OEM.

Perhaps what we need is an amp with variable second and third harmonic controls, so that we can dial in the exact mix that we prefer.  

BlueSound PowerNode.

2nd and 3rd harmonics pretty much same level.

@niodari The first harmonic is the fundamental frequency of the note itself.  So that's the big spike to the far left.  Thus the other harmonics begin with the second.

The reason why the same note/frequency played on a violin and a clarinet sounds different is--simplistically--because different instruments produce different combinations of harmonics... rather like different models of amplifiers!

@niodari 

Here's the measurement of the Technics SU-G700M2, which may not be exactly a class D amp, or a GaNFet amp, but which is something close.

As you'll see, some of the higher order harmonics are higher than one often sees, and normally you only want to see the second and third harmonics around that level.  John Atkinson commented:

"The fifth harmonic in both channels, the seventh harmonic in the left channel (blue trace), and the ninth harmonic in the right channel (red trace) were almost as high in level as the second and third harmonics. Although these harmonics are low in level, lying between –80dB (0.01%) and –70dB (0.03%), they could be audible at high listening levels in the region where the ear is most sensitive."