How can a system be judged with highly processed, non acoustic music?


I basically know what an instrument or human voice sounds like. I understand that almost all recordings, analog or digital, go through some level of processing. I also know that there are many, many recordings which strive to present a natural, real sound. To me, I can best judge a system playing lightly or non processed acoustic music.
This is also my preference for listening in general. And for me, it is vinyl.
mglik
For me yes....

Metallica is like a very good detailed " white and black" drawing...At best....

A lute piece very well recorded is like a color oil paintings...Or a rendition of Chopin or Listz at the piano....

The sonic "cues" are way more subtle and evoke way more subtle mix of emotions...For me....

i like the group "Nightwatch" for example but i listen to only the albums with their first female singer.... The voice add to the group something more poetic and more natural....a unique set of colors.... She was a classical singer educated....


 Amplified or electronically amplified  instruments for me sound more "white /black" pixellation...And natural acoustical sound more like oil paintings...




never enough Frogman ;-) all good.

best to you in the quest, check out 2L recordings download bench, some lovely work on display there….
I tend to not like 'acoustic music', so I can very easily judge a system based on what I DO like. In any case, at best, you are hearing what the producer wants you to hear. 
frogman -- Hey, thanks for the comparison vid. Routed it through the old hi-fi. As for making a choice among the three makes, all three axes offer up equivalent versions of the truth. The Bosendorfer gives me a just a little bit more power. The Fazioli a bit more sparkle & presence. The Steinway a bit more old-fashioned seriousness & comfort, i.e., the sense that this is what the classic/romantic composers probably actually heard when they composed.

I gotta say, though, that the YouTube was the proverbial beotch to get through. Each time I'd put it on, several minutes through it'd be hijacked by a different, abjectly inferior Piano YouTube that could not be gotten rid of. Eventually I was able to hear all three pianos go through their paces, but what a headache! It made me nostalgic for the time when, in L.A., I'd just get in the car and brave the traffic to different piano emporia.
I agree with your characterizations and might describe what I hear a little differently. Not sure it’s an issue of truth, but more of tradition vs more modern. A similar trend toward a certain kind of sound can be found with many manufacturers of acoustic instruments other than piano. In addition to what you describe, I would add that the Fazioli, a modern company, also has a hollowness and shouty quality that I don’t like, the Steinway (my favorite) has warmth and the best balanced sound, and the Bosendorfer is somewhere in the middle with more power than the Steinway. All great in their own way and, of course, there is the issue of feel and action which are important only to the player.
frogman -- I'll bet my memory is playing tricks on me, but I'm pretty sure that when I went to L.A.'s piano shops and played those three brands brands, it was only the Fazioli that gave me the shakes. It was only the Fazioli that compelled me to return to the dealer and drive them nuts with my horrible playing, once again.

I might want to say, too, that for a while I lived within walking distance of a very good piano store. And that I continue to love the early 20th Century, 52" Mason & Hamlin upright. I was compelled to buy it when the wife lost patience with the living room hogging Petrof Grand I'd been banging on previously.
It cannot be judged for accuracy.  Maybe timing, but not much else.  Amplified instruments do not provide an accurate point of reference sine the instruments; tone will be enslaved by the musical instruments amplifiers' distortions.  Even vocals can suffer from control-board-itis and compression.
Acoustic guitars also change over time and some are better than others, in fact much better even among the same models of the same brands. A late 30s Martin D-18? Astonishing or unplayable depending on the guitar's life over time...Richard Hoover of Santa Cruz says you gotta play the things to make 'em great.