A dominant 7th sharp 9 · Piano
A7♯9 Chord on Piano
The A7♯9 chord (A dominant 7th sharp 9) is built from the notes A, C#, E, G and C. The keyboard diagram below shows exactly which keys to press.
Chord diagrams
Notes in this chord
- A
- C♯
- E
- G
- C
Degrees: 1 – 3 – 5 – ♭7 – ♯9
How to play
To play A7♯9 on piano, press A, C#, E, G and C together. In root position the lowest note is A, 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 A7♯9 this structure sits on the root A, so the degrees 1 – 3 – 5 – ♭7 – ♯9 map onto A, C#, E, G and C.
Frequently asked questions
- Which notes are in the A7♯9 chord?
- A7♯9 contains the notes A, C#, E, G and C. Relative to the root these are the degrees 1 – 3 – 5 – ♭7 – ♯9.
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