I've not particularly vigorously compared various optical disc players over the years (having gotten my first one in the mid 80s) as I've not felt there was any difference to flesh out. I might still have an old cd changer from the 90s, and a few dvd players, but mostly I use newer bluray players. I've used their onboard dacs as well as dacs external to the players and just scratch my head with all these who hear differences in the dac particularly. Perhaps people thought they needed to fuss with a dac as much as a vinyl playback system or something? I heard definite improvements in a variety of ways over vinyl altogether, tho.