High quality recordings any genre

Here is a trifecta. Copland's Fanfare for the Common  Man, Appalachian Spring Suite, and his 3rd Symphony. Apart from excellent performances, the acoustics are superb. Hell I'd buy this even if I didn't like Copland all that much. The Fanfare could be a lease breaker if your system is up to it. :-)

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Try audiophile websites like Elusive Disc or Acoustic Sounds; there are a number of these and they specialize in great sounding, well-mastered recordings.

+1, @larsman Add NativeDSD to your list if you’re into downloads.