I find listening to a well done, well reproduced recording to be a real "upper" (meaning very stimulating), and in fact I avoid listening if I want to get to sleep within the following couple of hours. I don't generally listen to my system as background music; I want to be able to concentrate on it just as I would in a concert hall.
Which means first and foremost that the system has to be able to reproduce music, in this case mostly classical music, at realistic concert hall volumes cleanly, including in the bass region. And that means bass peaks in the range of 100 to 105 db, which can easily be reached on well recorded examples of a lot of symphonic music.
At the same time, I want harmonic and timbral accuracy in the mid-range. If there is a basic rightness in the midrange for the predominant instruments on any given recording, I find that my attention is drawn to them by their realism, and faults elsewhere in the spectrum, or even in the mid-range on other instruments that play subordinate roles, are less objectionable to me because my attention is grabbed by what is right about the recording (if it is REALLY right), not what is wrong. That is particularly so if any shortcomings elsewhere are subtractive in nature, rather than being additive colorations.
Next in line in my order of priorities are clean transient response, followed by imaging (it should be both large and well-focused).
I tend to think of pretty much all of these things as correlating with accuracy, resolution, and neutrality, but I don't pay a lot of attention to terminology and semantics. My feeling is that if something sounds really right, it is easy to recognize, and I don't pay a lot of attention to analyzing or characterizing why. It is when it doesn't sound right, and when what is wrong about the recording or its reproduction is bad enough to overshadow what is right, that the difficulties in analyzing and characterizing the problem arise.
Frankly, since the time I reached the point at which my system attained some semblance of high-end accuracy (which was in the 1980's), the biggest variable in all of this (at least with the classical music which comprises most of my listening) I have found to be the recordings themselves.
Consequently a disproportionately high percentage of my collection and my listening is to recordings that are either on audiophile-oriented labels or labels that are otherwise high quality. Examples being Chesky, Wilson, Sheffield, Telarc, reissues of early RCA and Mercury, Harmonia Mundi (both France and Germany), Astree, Valois, Accent, MoFi, Lyrinx/Syrinx, Reference Recordings, etc. Some of these labels I believe are no longer around, btw. Typical heavily multi-miked, heavily processed recordings from the major labels are usually a big letdown to me, no matter how good the performance may be.
That said, I also can very much enjoy some mono recordings from as far back as the 1940's and 1950's, such as a lot of Toscanini's, and recordings by vocalists such as Kathleen Ferrier and Renata Tebaldi.
Newbee -- Excellent thread idea!
A very happy Thanksgiving to all.