Chord sequence
Cmaj7 A7 Fm7 B♭7
In every key
Four-note rootless voicings in their two forms, with the 3rd or the 7th on the bottom, played over the root.
Heard in C major
Chords 3 to 4
Fm7 Bb7
Over Cmaj7 · Imaj7
The major scale and its modes are the most commonly used scales in western music.
Over A7 · V7/ii
Mode 6 of Blues
Over Fm7 · iv7
Mode 2 of Major
Over Bb7 · ♭VII7
Mode 4 of Melodic Minor