I take your report of perceived sonic differences at face value, no acusation of placebo affect. It it comes back to
@RichB ’s point above — without assurance of a common master, all we know is that something is going on, and we don’t know what.
My suspicion is that they are doing something in their ADC that introduces these audible effects. And assuming that’s true, my preference would be to instead have the “clean” version that sounds as close to the original analog as possible, and to instead generate the same effects through user-controllable (and defeatable) DSP.
I dont always to my music bit perfect. Right now in my main stereo rig I’m running a digital crossover to my sub, and it sounds pretty good to my ears, so I’m definitely open to the idea that my musical experience can be enhanced through DSP. I just like to be the one in control, instead of letting some company decide for me what effects sound best. But as long as they are doing it, at least it sounds good