The song "Ruby, My Dear" is performed only by Monk, Coleman Hawkins, Wilbur Ware, and Art Blakey.

As a result, the stereo mix has a more distant sound and Wilbur Ware's bass is much less audible.

Among other things, every musician found himself surrounded by a doubled quantity of microphones.”[10]In the notes to the 1986 Riverside Monk box, Keepnews wrote: "This was one of our very first stereo recordings (although the separate machine failed us on Crepuscule); confusingly, the monaural version has sometimes been used in reissues, but I have managed to include here in stereo form everything that is available in that form.

The 1967 "stereo" pressing (RS 3004) distributed by ABC Records was an "electronically reprocessed" version of the mono mix.

A 1977 Japanese vinyl version appears to be the first true stereo release that also includes the mono recording of "Crepuscule with Nellie".