Chord sequence

Cm7b5, B7#11, Bbm7, A7, Abmaj7

Cm7♭5 B7♯11 B♭m7 A7 A♭maj7

Tempo 120 BPM

Rootless Shells Guide tones Rooted shells Rooted Drop 2

Four-note rootless voicings in their two forms, with the 3rd or the 7th on the bottom, played over the root.

Customize each chord

Cm7b5
B7#11
Bbm7
A7
Abmaj7

Analysis

Heard in Ab major

Each chord's roman numeral and role in Ab major
Chord	Numeral	Role
Cm7♭5	?	Outside the key (iiiø7)
B7♯11	subV7♯11/ii	Tritone substitute for V7/ii
B♭m7	ii7	Subdominant
A7	subV7	Tritone substitute for V7
A♭maj7	Imaj7	Tonic

Progressions in these changes

Chords 3 to 5

Tritone Sub ii-V-I Progression in Ab

Bbm7 A7 Abmaj7

Scales to play