Watch the Week 8: Chromatic II - V's online guitar lesson by Bob Wolfman from Essential Guide To Jazz Blues Comping
"Chromatic II-V's" & "Chromatic II-V's (III-7)" 12 Bar Blues -
We've got two variations on the theme "chromatic" II - V's in this week's lesson. The significant difference is the use of the III-7 chord.
Chromatic II-V's 12 Bar Blues (With No Substitutions) -
Measure 2 moves from E-7b5 (the II-7b5) down to Eb7 (the SUB V) of D. Measure 3 moves from D-7 (VI-7) down to Db7 (SUBV) of C-7(II-7) of the target chord Bbmaj7. The Bbmaj7 is preceded by B7, which is another SubV chord. Measures 7 and 8 have consecutive descending chromatic II - V's, moving to measure 9...G-7(II-7) moving to Db7 (SubV) down to C7(V7/I) moves to Gb7(SubV) of F7...the I chord. Remaining chords are the turnaround again.