I made this comparison between the two Eversolo DMP A-6 units before Christmas but it was so dull, and not wishing to soil my reputation as a witty raconteur:-
But while I wait for my expensive new cables to undergo their 600 hour burn-in.
Level matching was easy peasy because they both have the same output voltages, I had to be more careful with the DMP A-8 comparison as that has slightly lower output on both RCA and XLR.
I played the same tracks through both, I use Roon ( excellent btw) which allows you not only to cue the tracks but also to switch instantly between Eversolo A-6s.
To be frank I didn't expect to hear a difference in terms of sound quality, the standard A-6 already measures so well ( see the Audio Science Review) and the only differences apart from the gold badgework, amber illumination around the volume control a different op-amp and 'femto' clocks oh and £400!
This doesn't diminish them they are both excellent products, well made and packed with useful features, but one simply cannot get 'better' than audibly transparent.
The more interesting question is just how much. distortion do you have to add before one can reliably hear a difference.