My favorite system demo--either in CD or DVD-Audio format--is Pat Metheny Group's "Imaginary Day"--it took a Grammy back in the day for Best Jazz Performance, and was well engineered. The two formats have very different flavor . . . I love both for their respective strengths in showing off 2-channel and surround systems (although the CD sounds sweet in DSP surround modes as well!)
Now, my favorite aside, for outstanding
recordings look no further than the Stereophile CD's (
here ) . . . they are beyond clean, and their engineering is on a completely different level than mass-market CD fare. John Atkinson builds a soundstage that will just flat blow your mind; "Rendezvous" (their jazz cd) gives me chills . . . you can clearly identify the placement of each member of the quintet, making them almost visible.
Many of the Telarc Digital recordings are nice as well, though some are just a bit too heavy-handed on digital effects to my taste.