Music to test with:

People buy HIEND equipment to listen to the music they like. Classical music is no more intrinsicly better than rock than Bach is better than Mozart. Why would someone who loves Frank Zappa or Neil Young (neither of which I like) buy a Berloiz album to test their gear?

Actually, there is an excellent reason for using music created with natural acoustic instruments rather than synthesizers or other esoteric electronica. We know (at least musically educated people know) what an oboe, piano, violin, upright bass, or snare drum is suppose to sound like. Nobody really knows what an electric guitar washed through five or six little black boxes is supposed to sound like.

If your concern is only to find a sound that you like, then you can of course use any source you want. If you desire an accurate reproduction system, you'd better start with a known source.

will

Thank you Bishopwill!

Having been to many concerts in different theaters or concert halls from the US to western Europe I have to say that each hall has sounded different. Each time the viola has sounded like a viola but it never sounded the same as in the last hall. Does that mean they used a different viola or was it run through a series of black boxes that caused the sound to change? To say that unamplified flutes are they only music by which to judge the quality of a piece of equipment is ludacrous. What do you know about the acoustics of the setting? Something you might think is the problem of the equipment might just as easily be an acoustic characteristic of the concert hall.
I again ask the question; what is the point of using music with which you are not familiar to test something.
I'm not suggesting ssing2 is wrong, for him/her that might be the perfect piece of music. I'm sure you are not suggesting that fans of heavy metal or techno pop have no place in hi-end audio.
I am looking for suggestions to add to my collection to help in the auditioning process. I did not think I would have to defend my preferences of a broad spectum of music.

In addition to the common James Taylor-type recordings, these are some of my other favorite "demo" discs:

City of Angels - Soundrack
I am Sam - Soundtrack
Ben Folds - Rockin' the Suburbs
Thomas Dolby - Alien ate my Buick
Dire Straits - Brothers in Arms XRCD2
Grateful Dead - Dicks Picks 17
Ray Brown - Soular Energy
Dave's True Story - Sex without Bodies
Apollo 13 Soundtrack (track 20)
The Firm Soundtrack

(I know, a lot of soundtracks, but I like that they have various artists on a single disc and usually offer a consistant recording quality across the disc.)