Swap one chord in a progression and hear the difference
G7 gives way to the dominant a tritone away: D flat 7, the bII7. The two share the tritone inside them, the third and the seventh trading roles, which is why D flat 7 resolves where G7 would.
Reharmonizing is swapping a chord for a more colorful one without changing where the music is going: the other chords of the progression stay where they are.
In the lessonTritone substitutionTap a chord to hear it and see it on the neck.
Dm7 G7 Cmaj7 becomes Dm7 D flat 7 Cmaj7: G7 gives way to D flat 7.
G7 and D flat 7 share 2 notes: B (Cb in Db7) and F.
Shares at least half the notes, and the voices that change move 2 semitones or less in total.
Shape 1 of 5, C shape: frets 2 to 4. The root is at fret 4 on string 5 and at fret 2 on string 2. Strings 6 and 1 do not sound.
Showing the degree of each note.