Sixth add ninth combines a major sixth chord with an added ninth—a bright, modern major color that is wider than a triad but still avoids dominant tension from a seventh. Charts may show C6/9 or C6(add9). It is common in funk, soul, R&B, and fusion keyboard voicings where the band wants sparkle on a major or IV chord without turning it into a maj7 or a dominant.
How it’s built
Take a major triad, add the major sixth, then add the major ninth above the root. In C6/9: C–E–G–A–D. The sixth and ninth together create a wide, open sound; the chord differs from major add9 because it includes the sixth, and it differs from dominant sounds because it does not include a minor seventh.
Usage
In soul and funk, 6/9 voicings appear on I and IV as stable, “expensive” major pads. In jazz-funk and fusion, keyboard players use 6/9 as a clean color when the harmony is modal or static. In pop production, 6/9 stacks add shimmer to choruses without pulling like a V chord.
Examples
- Funk and soul keyboard voicings — I6/9 and IV6/9 colors in grooves
- Fusion and jazz-funk — major stacks with sixth and ninth extensions
- Contemporary pop and R&B arranging — wide major pads on tonic areas
Play
Keep the ninth and sixth audible in the upper structure; avoid doubling that obscures those color tones. This chord usually works best when the bass clearly states the root so the harmony reads as “major color,” not as a confusing inversion of another chord.
