Add production quality and mastering to that mix too… I find once your sound system is up to a certain standard, production matters so much. Still amazes me when I play some pop music that SHOULD sound good and it’s slammed to the point of distortion. I generally won’t hear it on budget systems but I’ll sure as hell hear it with my good system. Then I’ll play something well produced and mastered and it will sound absolutely fantastic.
Realistically, if the device’s SNR is above 110db and distortion <0.01%…. Can you hear the difference? Is it then more about frequency response and how it interacts with your other equipment, room acoustics etc. ?
And then we’ve got our own psychological biases to try and combat. I’ve convinced myself something sounds better plenty of times before swapping back and forth around 10 times until I finally realise there really is no real perceptible difference.
I’m probably biased towards the analogue distortion introduced by analogue mixers simply because I’ve used them for so many years. For digital, the db4 I had for a while sounded pretty bloody good, so did the Rane MP2015 (very clean), I haven’t used any of the new Pioneer mixers. I mean really, the x1850 didn’t sound too bad, I was being incredibly fussy when I decided to change mixers.
Back to the original topic, also consider what sort of mixer you want. Most high end expensive mixers should sound good enough really. It’s also worth considering the layout of the mixer, metering, how you want to mix, fader curves, if it’s analogue do the filters pop?And on and on…