This set was recorded at the Ann Arbor Blues and Jazz Festival. The concert was recorded by Atlantic Records, but it remains commercially unissued. A tape supplied by the Detroit Jazz Heritage Society was broadcast on WCBN-FM, the University of Michigan student radio station. The concert was also broadcast in the late 1970s by WNRZ-FM, Ann Arbor.

Both broadcast tapes are incomplete, and there are significant differences in times. One copy of the WNRZ tape is more than 10% slow! The WCBN version begins with an introduction by the disk jockey (who wrongly identifies the saxophonist as Dave Liebman), cuts off "Honky Tonk" near the end, inserts a commercial break toward the end of "Black Satin," and contains only a fragment (0:45) of "Right Off." The WNRZ version begins a couple minutes into "Chieftain" but includes the remainder of the concert intact. As mentioned above, the master tape of this version is quite slow; times listed here are from a speed-corrected version of that tape.

"Chieftain" was first recorded in the studio on August 23 . It is commonly performed in a medley with "Rated X" during this period. The transition occurs when Henderson begins the distinctive (and insistent) el-b vamp. I am grateful to Jim Szabo for discussion on these tunes.

The Davis Nonet was busy during this period: Paul's Mall, Boston (September 14-17); Spectrum, Philadelphia (September 23); Lincoln Center, New York (September 29); Stanford University Amphitheater, Palo Alto (October 1); Civic Theatre, San Diego (October 8).