It seems that the game changer for the SQ from the recent class D amps is the TI 3255 amp chip they use. What impressed me with the ZA3 is its transparency. It takes whatever is fed to it and reproduces it faithfully without any embellishments. Adding the DAC does about the same thing in what it passes through to the amp. As of now I don't use tone controls at all except for a software based EQ program for the computer. Even then, the only slider I have adjusted is a slight boost at 31hz to give the L100t3s a little more low end bass past their rated 35hz bottom. I feel like I am hearing music, for the most part, as the original sound engineer intended.I plan on trying one of those amps soon. Just to see what all the fuss is about with Class D. I've had a few Class D amps in the past but that was well over 10 years ago. I'm sure things have changed a bit since then.
The crazy thing is that these newer budget class D amps have only been out for less than two years. The 2-3 biggest players in this market are producing new improved products at a fast pace. Especially Fosi and AIYIMA but, IMO, Fosi is a little better than AIYIMA at the moment. In another 1-2 years I think they will be producing components that would have been unthinkable just a few years ago regarding price versus performance. Fosi just came out with a DAC for under $150 (includes discount) that has balanced outputs and HDMI ARC, coax, optical, bluetooth and USB inputs. Plus, it has a remote control, volume adjustment capability and a nice LED display. So far, it has mostly received very solid reviews. Also, many of these newer class D amps can be set to run in mono mode (the Fosi V3 Mono is fulltime mono) which makes it very easy to economically run a dual mono setup.
Awesome