← A♯ Altered on Trombone (tenor clef)
A♯ 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 1A♯·D·G♯
Degree 2 · Degree 2B·E·A♯
Degree 3 · III(4)C#(4)
Degree 4 · Degree 4D·G♯·C♯
Degree 5 · Degree 5E·A♯·D
Degree 6 · VI(4)F#(4)
Degree 7 · VII(4)G#(4)