Did DAC's improved thrue time? Don't you think they will future improve more?
Certainly they have got simpler and cheaper. Very much so. Whether as a result of this their sound quality has effectively improved too is debatable.
Clever people like
@Miska have also written code to get still more linearity from digital.
My belief is that I am unable to hear distortion once the level is -60dB or better (and the loudspeaker people talk about much more than this being inaudible) I don't notice noise on recordings of music if it is lower than -80dB.
So for me, whilst I know that DAC's technical specs and measured performance has improved since the early days, I don't find the gain to be audible, and therefore pointless for music listening as opposed to equipment and recording marketing.
I do plan to compare my
Sony DAS-702ES with my RME ADI-2 Pro with matched levels one day but have not yet, I don't enjoy comparing kit when I could be listening to music. Last time I carefully compared DACs, around 10 years ago, they were insufficiently different to consistently know which was playing.
There is a far, far greater difference in SQ between recordings than there ever has been in digital equipment IME.
After all there are a huge number of people who listen to LPs and are happy with the SQ and it is about 11-bit equivalent and whilst there may be some output from some cartridges at frequencies >20kHz in all liklihood it will be spurious and/or effected by roll off or resonance than of resonable quality.
DACs were already better than any part of an LP replay system when they came out, so if LP is OK (it usually is for me) the DAC improvements have been of academic or production engineering (well worthwhile) benefit, not SQ.
IMHO