G major · Tritone substitution
Tritone substitutions in G major








Every dominant in G major, and its substitute
- D7V7GsubV7G
A♭7 substitutes for D7, the dominant of G major. They share the same tritone, so the bass can fall a semitone instead of a fifth. Shared notes: F♯ and C in D7, G♭ and C in A♭7.
- E7V7/iiAmsubV7/iiAm
B♭7 substitutes for E7, the dominant of A minor. They share the same tritone, so the bass can fall a semitone instead of a fifth. Shared notes: G♯ and D in E7, A♭ and D in B♭7.
- V7/iiiBmC7subV7/iiiBm
C7 substitutes for F♯7, the dominant of B minor. They share the same tritone, so the bass can fall a semitone instead of a fifth. Shared notes: A♯ and E in F♯7, B♭ and E in C7.
- G7V7/IVCsubV7/IVC
C♯7 substitutes for G7, the dominant of C major. They share the same tritone, so the bass can fall a semitone instead of a fifth. Shared notes: B and F in G7, B and E♯ in C♯7.
- A7V7/VDsubV7/VD
E♭7 substitutes for A7, the dominant of D major. They share the same tritone, so the bass can fall a semitone instead of a fifth. Shared notes: C♯ and G in A7, D♭ and G in E♭7.
- B7V7/viEmF7subV7/viEm
F7 substitutes for B7, the dominant of E minor. They share the same tritone, so the bass can fall a semitone instead of a fifth. Shared notes: D♯ and A in B7, E♭ and A in F7.
Why the substitute works
What makes a dominant seventh want to resolve is the tritone between its third and its seventh. Move the root a tritone and that interval is still there, with its two notes swapped: the third becomes the seventh and the seventh becomes the third. So the substitute pulls to the same place, and the bass slides down a semitone to get there.
Play the two buttons in each row one after the other. Same arrival, different road.