By audiophile standards, the CD sound quality of the1976 Karajan series verges on good. I have both the original Deutsche Grammaphon CD release and the remastered SACD release and can definitely recommend the latter, though if you want the ultimate sound quality you'll need to pick up a more recent 'Pure DSD' recording such as that conducted by Runnicles on Telarc. The Karajan performance is so good that combined with decent (but not great) sound you shouldn't have any problem staying engaged, but the Telarc DSD version is decidely superior in every way when it comes to sonics. SACD has been a godsend for classical music lovers. Even my unmodded Sony DVP-s9000es DVD/CD/SACD player (avg. used price ~$425-550) trounces my almost four grand redbook Linn Ikemi cdp when playing back the SACD layers of *certain* classical recordings vs. the redbook layer on the Ikemi. For redbook only, you're best bet for sound quality in classical is going to be anything on the Reference Recordings label (most or all of which also support HDCD).