F Altered — Quartal voicings
Three-note stacks of fourths, one per scale degree — the open, ambiguous voicing-flavour McCoy Tyner and Bill Evans built modal-era jazz around (the 'So What' chord).
All 7 quartal voicings in sequence
Degree 1 · Degree 1F·B𝄫·E♭
Degree 2 · Degree 2G♭·C♭·F
Degree 3 · III(4)Ab(4)
Degree 4 · Degree 4B𝄫·E♭·A♭
Degree 5 · Degree 5C♭·F·B𝄫
Degree 6 · VI(4)Db(4)
Degree 7 · VII(4)Eb(4)