What is a high end stereo SUPPOSED to sound like?

Well a very slight amount of euphonic coloring would be best IMO. (unless you have unlimited funds to blow on equipment)
I have it in my VAC Standard preamp i use just as a glorified tube buffer to ameliorate the digital glare from my only slightly better than average digital front end.
If i had $50,000 to blow in a digital front end, I would not need the VAC.
So IMO a little euphonic coloration is better than a little 'honest but crap sounding stuff". (If that helps any.)
And yeas, equipment CAN be found which makes most recordings sound good, and still be close to the truth.
(IE not 'just' masked with colorations..)
Other may and will disagree. Such is life.

Foster_9,
Well said, that`s my standard also.
Regards,

Like the telltale rustle made by ghosts of c-notes past...

If it's true hi-fi, it 'should' sound like the original source. However no stereo system does this, esp if you are sitting in front of it. My system which is very much lo/mid-fi CAN sound like a live artist is performing if I am listening to it while in a room other than the room the sytem is located, and it's solo or small group music. No stsero system will make you think the Chicago symphony is in your house, but maybe Joan Baez. The term 'high end' is not revelant. My system is just as realistic as any on this site i.e. it seldom sounds like the real thing. But it does satisfy my need to listen to music, and I cannot imagine being without it.

CDC,

All systems, even the uber expensive ones, impart color of some type. Hi-end is all about determining what color you want and can live with long term. As to your 3 points:

1] A system will make a recording sound different than what it was monitored on...that may be better or worse to you
2] Yes, a system will consistently impart its unique color on whatever it plays
3]The best you can hope for is a system that colors your music the way your ears think it should be colored