The related II · Secondary dominants · Music theory
Just as V⁷ is usually preceded by IIm⁷, a secondary dominant can be preceded by its own II: the minor chord with a minor 7th a perfect fourth below it. Am7…
The related II
Just as V⁷ is usually preceded by IIm⁷, a secondary dominant can be preceded by its own II: the minor chord with a minor 7th a perfect fourth below it. Am7 before D7 does toward G what Dm7 before G7 does toward C. The result is a II – V – I toward another degree, marked in analysis with a bracket.
If the destination is a minor chord, that II is half-diminished, as II is in minor: Bm7(♭5) – E7 – Am. Sometimes the related II is diatonic, as Am7 toward G, and sometimes not. And sometimes it appears alone, because the context is so clear that the dominant can wait.