As the VD major
- ii7Em7
- V7♯9A7♯9
- Imaj7Dmaj7
A7♯9 is the chord that wants to resolve, so ending the loop on it hands straight back to the top.
A7♯9 Chord: Guitar, Piano and Notes
The A7♯9 chord is a altered dominant seventh chord built on the root note A. Its notes are A, C♯, E, G and B♯.
Transpose
Quality
Short answer
Dominant seventh sharp nine chords sound gritty and bluesy at once, the clash of a major third against a sharp ninth that reads to the ear like a minor third. Funk, rock and soul horn sections lean hard on this one chord.
- Notes
- A · C♯ · E · G · B♯
- Formula
- 1 · 3 · 5 · ♭7 · ♯9
- Semitones
- 0 · 4 · 7 · 10 · 15
- Note
- A
- Quality
- Dominant 7♯9
- Symbol
- A7♯9
A7♯9 on piano
5 notesView:
Switch to the interactive diagram to hear the chord, change voicing and swap finger numbers for note names.
To play A7♯9 on piano, place your right hand with your thumb on A, index finger on B♯, middle finger on C♯, ring finger on E and little finger on G. Press the keys together and listen for an even sound. On the keyboard C♯ is a black key and A, E, G and B♯ are white. B♯ is the key you'd normally call C. Practice moving in and out of the chord slowly, then bring in a metronome.
- A1
- B♯♯9
- C♯3
- E5
- G♭7
A7♯9 on guitar
View:
Switch to the interactive diagram to hear the chord, change voicing and swap finger numbers for note names.
On guitar, A7♯9 is commonly played with the voicing shown above. The fretted notes sit between frets 2 and 5. Strings 3 and 1 ring open.
A · C♯ · E · G · B♯
Play A7♯9 on the online piano
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A7♯9 chord notes
| Degree | Interval | Semitones | Note | Hear |
|---|---|---|---|---|
| 1 | Root | 0 | A | |
| 3 | Major third | 4 | C♯(C#) | |
| 5 | Perfect fifth | 7 | E | |
| ♭7 | Minor seventh | 10 | G | |
| ♯9 | Augmented ninth | 15 | B♯(B#) |
How to use the A7♯9 chord
The A7♯9 chord is built from a root, a major third, a perfect fifth, a minor seventh and an augmented ninth. Start at the root A and stack the intervals to get the whole chord: A, C♯, E, G and B♯. The same formula gives you the chord in any other key.
Dominant seventh sharp nine chords drive funk, blues-rock and fusion as the tonic of a dominant-based vamp, not only as a V chord. Whole grooves in soul and rock guitar are built around this one chord.
How A7♯9 differs from similar chords
A7♯9 holds both a major third and a raised ninth that sounds like a minor third, so it is major and minor at once. That clash separates it from A7♭9, where the ninth is lowered, and from A9, where it is natural. Guitarists often call it the Hendrix chord.
Where A7♯9 is used
A dominant chord wants to resolve. Its home is the V of a major key - and the I of a blues, where the pull never lets up.
Questions people ask
- What notes are in the A7♯9 chord?
- The A7♯9 chord contains A, C♯, E, G and B♯ (A, C#, E, G and B# in plain text).
- Is the A7♯9 chord major or minor?
- A7♯9 is a altered dominant seventh chord. Dominant seventh sharp nine chords sound gritty and bluesy at once, the clash of a major third against a sharp ninth that reads to the ear like a minor third. Funk, rock and soul horn sections lean hard on this one chord.
- How do you play A7♯9 on piano?
- Place your fingers on A, C♯, E, G and B♯ and play them together. The root usually goes to the little finger of the left hand, the upper notes to the right. On the keyboard C♯ is a black key and A, E, G and B♯ are white. B♯ is the key you'd normally call C.
- How do you play A7♯9 on guitar?
- Use the fingering in the diagram above. The fretted notes sit between frets 2 and 5. Strings 3 and 1 ring open.
- What chords work well with A7♯9?
- A7♯9 pairs naturally with the chords in the related section: a perfect fifth up or down, the relative major or minor, and anything sharing two notes with it.