7799 / 18210 · Workshop 61 — Melodic Minor as a Practical Color System: Altered Dominants, Lydian Dominant, Minor-Major Harmony, Locrian ♮2, and Choosing Tension by Destination← prev⊞ allnext →
61.58Level 16 — tritone substitution connection
G7alt and D♭7 Lydian dominant are closely related.
Why?
They contain many of the same pitches and share the critical tritone:
B-F
which enharmonically corresponds to:
C♭-F
inside D♭7.
So one dominant can morph into its tritone substitute.