Chord sequence

Abm7, Eb7, Dmaj7, Cb7, Bbmaj7, G7, Gbmaj7

A♭m7 E♭7 Dmaj7 C♭7 B♭maj7 G7 G♭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

Abm7
Eb7
Dmaj7
Cb7
Bbmaj7
G7
Gbmaj7

Analysis

Heard in Gb major

Each chord's roman numeral and role in Gb major
Chord	Numeral	Role
A♭m7	ii7	Subdominant
E♭7	subV7/♭VI	Tritone substitute for V7/bVI
Dmaj7	♭VImaj7	Borrowed from Gb minor
C♭7	subV7/III	Tritone substitute for V7/III
B♭maj7	?	Outside the key (IIImaj7)
G7	subV7	Tritone substitute for V7
G♭maj7	Imaj7	Tonic

Scales to play