C dominant 7th sharp 9 · Piano
C7♯9 Chord on Piano
The C7♯9 chord (C dominant 7th sharp 9) is built from the notes C, E, G, A# and D#. The keyboard diagram below shows exactly which keys to press.
Chord diagrams
Notes in this chord
- C
- E
- G
- A♯
- D♯
Degrees: 1 – 3 – 5 – ♭7 – ♯9
How to play
To play C7♯9 on piano, press C, E, G, A# and D# together. In root position the lowest note is C, and the finger numbers follow the keys left to right in the diagram.
Theory behind the chord
Often called the Hendrix chord, the 7♯9 stacks a sharpened ninth over a dominant seventh. Major and minor thirds sound at once, producing the gritty clash that defines psychedelic rock and funk. On C7♯9 this structure sits on the root C, so the degrees 1 – 3 – 5 – ♭7 – ♯9 map onto C, E, G, A# and D#.
Frequently asked questions
- Which notes are in the C7♯9 chord?
- C7♯9 contains the notes C, E, G, A# and D#. Relative to the root these are the degrees 1 – 3 – 5 – ♭7 – ♯9.
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