Secondary Dominants and Borrowed Chords: Adding Colour Beyond the Key

Sat, 04 Apr 2026 09:00:00 +0000

You are playing a song in C major and every chord comes from the diatonic set — C, Dm, Em, F, G, Am, Bdim. It sounds good, but it also sounds predictable. Then a songwriter drops in an A7 chord. It is not in the key. It contains a C♯, a note that does not belong to C major at all. Yet it sounds completely natural — even exciting — because it pulls your ear powerfully toward the Dm that follows. That A7 is a secondary dominant, and it is one of the most common and effective ways to add harmonic colour without leaving the key entirely.

Borrowed Chords on Interactive Chord Finder

Secondary Dominants and Borrowed Chords: Adding Colour Beyond the Key