Señor Blues

I don't post copyrighted material, but this is a handwritten harmony part, and it's not for profit, instructional only. If one counts slowly, Señor Blues is indeed a 12 bar blues. If the triplet eighth notes are at 120bpm, the slow count would be 40bpm - much easier for the horns to conceptualize in slow 4/4 with a triplet feel! Reading the part is much easier in 12/8 compared to 6/8 because of fewer bar lines...

In the key of Eb minor, the minor i chord is voiced as an Ab13, from the bottom up Gb, Bb, C, F. That's on the piano. For guitar, those are the notes you want in your chord, call it an Ebm6/9 - the bass pattern emphasizes the root.

Measure 5 & 6 of this blues use a B13 chord (actually a Cb chord in the key signature) so on the piano one would simply move the 1st voicing up 3 half-steps. Maybe moving 3 frets up on the guitar would work. (Gbm6/9 over Cb in the bass?!) Measures 7-8 are back to the same pattern, same inversion as the first 4 bars.

The cadence in meas. 9-10 is simply Bb7 - Ab7 and back to Ebm(6/9) with no turn-around. The Bb7 and Ab7 sound fine with no third - and they also sound good as tri-tone voicings (3 and b7). More than a little finesse is required here.

Measures 11-12 are "on the one" - and there are sections of the tune arranged to stay on the minor i vamp. Pianist Horace Silver wrote it - upright bass players get cramps from the brutal 12/8 ostinato! There are a couple or three different recordings of this by Horace, one has a vocal by Bill Henderson. Taj Mahal did a good version, and vocalist Mark Murphy also did it (in C minor).