Chord sequence

C#m7, C7, Bm7, Bb7

C♯m7 C7 Bm7 B♭7

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

C#m7
C7
Bm7
Bb7

Analysis

Heard in A major

Each chord's roman numeral and role in A major
Chord	Numeral	Role
C♯m7	iii7	Diatonic
C7	subV7/ii	Tritone substitute for V7/ii
Bm7	ii7	Subdominant
B♭7	?	Outside the key (bII7)

Progressions in these changes

All the chords

Chromatic iii-bIII-ii-bII Progression in A

The iii-VI-ii-V turnaround with both dominants replaced by tritone substitutes, so the roots descend by half steps from iii to I.

Scales to play