It is a very good question mglik and one I have thought about a lot and first wrote about going back to the early 90’s. It is nowhere near easy with synth, but neither is it all that simple even with all minimalist recorded and classical acoustic instruments. Not even solo human voice. All these no matter how carefully recorded are altered and colored all kinds of ways by the recording venue itself. There really is no Rosetta Stone, no silver bullet, nothing we can grab hold of. Probably because there is nothing there to begin with, but that is another subject for another time.
Anyway, what I learned is yes you most certainly can judge and evaluate and build a high end system using highly processed non-acoustic music. It really is not any different than what it takes to do it with all acoustic minimally processed music. In both cases you simply have to slowly and gradually over time build up a knowledge base of how things sound through your system.
This is a seriously big challenge. Not least because it is completely at odds with the conventional wisdom and the prevailing advice parroted by so many of the importance of having a "reference" whatever. Reference recording. Reference speaker. Reference system. Whatever.
You want to to do it, seriously do it, let me give you the news: There is no reference! None! None at all! Nowhere! Best thing I can ever tell you, whatever you think is a reference, it is no more a reference than a meter, which is to say no reference at all.
All we can do is listen to a lot of different stuff, and the more the better, and try and look for patterns. We can’t say what is "bright" or "harsh" or "lush" or anything based on any one recording, other than relative to another, because we can never know for sure if it is indeed the recording. With records we cannot even know that much, because it may well indeed be the individual pressing copy and nothing to do with the recording! We must at all times keep an open mind.
We talk for simplicity sake as if this weren't so. But if you want to take it seriously that is the first thing to understand, most of what we talk about is for simplicity sake. Got to keep straight what is, and what we pretend is for the sake of simplifying things down to the little bits we try and pretend to understand.
You see what a phenomenally big challenge this is? And yet, when we do it right.... I spent the vast majority of my time listening to rock and hardly any classical or jazz. Never once in 30 years did anything, not one component or tweak, with the aim of making a sax or violin or string bass sound better. Not one time. All the great improvements I heard were with plain old U2 Tom Petty etc rock and roll. Yet lo and behold, now I put on Brubeck or Miles and oh my God does it sound right!
So it ain’t easy. But it can be done.