|Excerpted from Speaking of Jazz: Essays and Attitudes:
I sometimes create modern out chord successions over which I play my normal bluesy stuff, so it puts my blues licks in a different context, rather than learning to create lines from the chords. The compositional process for this piece began with a haunting subconscious near-obsession with the opening four-note motive, Bb, Db, Eb, F and its attendant rhythm, which gradually developed itself into a blues melody as I was going about my business going about my business over a period of several months. When it felt complete, I wrote it down, and then sat down at the piano and wrote its non-functional chord succession and the ostinato bass line.
This is an eight-bar blues in the form of a Passacaglia, a piece which has a strong recurring, descending bass ostinato. The melody is based on the following Pentachord (five-note) Melody Pitch Collection on (not in, since this piece is not tonal) the following blues pc: Bb: Bb, Db, Eb, E, F, Bb—(Minor blues scales with no seventh, Ab). The stepwise descending (and then ascending) non-functional chord succession (also on Bb) is as follows (at two beats per chord):
//: Bbm, Ab7sus4 / GbMA7, E7-5 / Eb7sus4, Dbm9 / C7-5, B+MA7 / Bbm, C7-5+9 / Db+MA7, Eb7sus4 / E+MA7, F7sus4 /
G7-5+9, A7-5 -9 :// (Bbsus/B)
Note that the final chord in the coda is a Bbsus/B. This tetrachord (four-note pc), which contains no seventh, acts as a voicing of a BMA7-5, only the root in the bass is separated from the rest of the otherwise close-position voicing. The root progression is also a strong line, which becomes more obvious as you sing it two or four times as fast.
With regard to the editorial process, this composition, in its first life, was extremely long, and contained several themes, changes of rhythmic feel, meter and key: Nobody could play it, so I threw it all out and asked myself what it was that inspired me to write it in the first place. Since I then decided it was the first eight measures, I kept that—and it was enough. Now it is performed often. I've also found that it can be played in any rhythmic style: slow swing, samba, funk, Latin—even reggae! I play blues licks over this without any regard to making changes. Indeed, I often build entire improvisations on the Blues Melody PC alone.
Here it is below: