IMO, the subject of recording speed is as thought-provoking as it is unknowable, and at any rate is of secondary importance to "correct" playback speed. In classical music, it's usually rather straightforward: play the recording at a speed that puts it in the original key, as written. (A caution: vocal music, especially opera arias and Lieder, may sometimes be performed at a transposed pitch, for artistic reasons and/or to suit the voice. This practice introduces a variable that lends interest and ambiguity to the discussion, if not the performance: live with it, and enjoy!). As for jazz, strong consideration, indeed preference, should be given to a playback speed that puts the pitch level in a flat key, commonly F, Bb, or Eb major and their relative minors d, g, and c respectively; also C maj./a min. Ditto for popular music, although written-out arrangements may venture into sharp keys such as G maj. (e min.) and D maj. (b min.). These are general guidelines that will be valid in most, but perhaps not all, instances. Since playback speed also affects tempo, the final result should be reasonable with respect to both pitch and tempo. Anything that sounds like chipmunks on uppers is to be avoided (unless, of course, it *is* chipmunks on uppers).
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