Chord sequence
Gm7 Em7♭5 Am7♭5 A♭7♯11
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 G minor
Over Gm7 · i7
Mode 2 of Major
Over Em7b5 · viø7
Mode 7 of Major
Over Am7b5 · iiø7
Over Ab7#11 · subV7♯11
Mode 4 of Melodic Minor