Track 6 from George Russell's 1961 album "Ezz-thetics": A Thelonious Monk composition "'Round Midnight".
The producer for the "Ezz-thetics" sessions was Orrin Keepnews and the band was:
George Russell - piano, arranger
Don Ellis - trumpet
Dave Baker - trombone
Eric Dolphy - alto sax and bass clarinet (tracks 2,4, and 6 only)
Steve Swallow - bass
Joe Hunt drums