2786 / 18210 · Workshop 9 — “Take the A Train”: Dominant Color, ♯11, Secondary Dominants, and Writing Lines Through Static Harmony← prev⊞ allnext →
9.2What would D7 normally do?
D7 is normally:
V7/V
in C.
Meaning:
D7 → G7.
Because D is the dominant of G.
So theoretically:
D7 → G7 → C
is a secondary-dominant chain.
But in a jazz tune, D7 may be prolonged long enough that it becomes a whole temporary sound-world rather than merely a quick passing dominant.
That is the key lesson.