lol, got one of those boards to try back when I was playing around with ES9038Q2M. Didn't like the sound, have heard better from that chip.
Yep, as well as what is likely some kind of feed-forward distortion cancellation to account for common layout errors and known internal nonlinearities.
JohnW said he thought ESS harmonic distortion compensation sounded best when disabled. Other people seem to like it though. IME ESS dacs sound best when operated in fully synchronous mode. ASRC PPLL (polyphase locked loop) jitter maybe could have something to do with it. As with PLLs it seems to help to have clean power rails.
just a test of MP3 decoder, (floating point ) , i wold say: sound is good - no clear difference to uncompressed PCM ; at least at 320 kb MP3 ;
1.1 kHz sin test :
1.1 kHz sin test :