Bbm7b5, Eb7alt, Cbm7, E7, Gbmaj7 in Gb

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

Analysis

Heard in Gb major

Each chord's roman numeral and role in Gb major
Chord	Numeral	Role
B♭m7♭5	iiiø7	ii of the ii-V to Eb7alt
E♭7alt	V7alt/ii	Secondary dominant, unresolved
C♭m7	iv7	Borrowed from Gb minor
E7	♭VII7	Borrowed from Gb minor
G♭maj7	Imaj7	Tonic