F Lydian — 7th chords
Four-note stacks of thirds on each degree — root, 3rd, 5th, 7th. The added 7th gives jazz, gospel, and modern classical voicings their distinctive colour.
All 7 seventh chords in sequence
Degree 1 · Imaj7Fmaj7
Degree 2 · II7G7
Degree 3 · iii7Am7
Degree 4 · iv°7Bm7b5
Degree 5 · Vmaj7Cmaj7
Degree 6 · vi7Dm7
Degree 7 · vii7Em7