As the VD major
- ii7Em7
- V9A9
- Imaj7Dmaj7
A9 is the chord that wants to resolve, so ending the loop on it hands straight back to the top.
A9 Chord: Guitar, Piano and Notes
The A9 chord is a dominant ninth chord built on the root note A. Its notes are A, C♯, E, G and B.
Transpose
Quality
Short answer
Dominant ninth chords are a dominant seventh with extra shine. The ninth on top softens the bite of the tritone below it, which is why funk, soul and blues rhythm guitar lives on this chord.
- Notes
- A · C♯ · E · G · B
- Formula
- 1 · 3 · 5 · ♭7 · 9
- Semitones
- 0 · 4 · 7 · 10 · 14
- Note
- A
- Quality
- Dominant 9
- Symbol
- A9
A9 on piano
5 notesView:
Switch to the interactive diagram to hear the chord, change voicing and swap finger numbers for note names.
To play A9 on piano, place your right hand with your thumb on A, index finger on C♯, middle finger on E, ring finger on G and little finger on B. 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. Practice moving in and out of the chord slowly, then bring in a metronome.
- A1
- C♯3
- E5
- G♭7
- B9
A9 on guitar
View:
Switch to the interactive diagram to hear the chord, change voicing and swap finger numbers for note names.
On guitar, A9 is commonly played with the voicing shown above. The fretted notes sit between frets 2 and 5. Strings 3, 2 and 1 ring open.
A · C♯ · E · G · B
Try A9 on the virtual piano
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A9 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 | Major ninth | 14 | B |
How to use the A9 chord
The A9 chord is built from a root, a major third, a perfect fifth, a minor seventh and a major 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 ninth chords take the place of a plain dominant seventh in blues, funk, soul and jazz. As the V9 they resolve just like a V7 does, only with more colour on the way.
How A9 differs from similar chords
A9 is A7 with a major ninth on top, so it keeps the dominant pull of the tritone. It differs from Amaj9 in the seventh, minor rather than major, and from Aadd9, which has no seventh at all. In A7♭9 and A7♯9 the same ninth is moved a half step down or up.
Where A9 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 A9 chord?
- The A9 chord contains A, C♯, E, G and B (A, C#, E, G and B in plain text).
- Is the A9 chord major or minor?
- A9 is a dominant ninth chord. Dominant ninth chords are a dominant seventh with extra shine. The ninth on top softens the bite of the tritone below it, which is why funk, soul and blues rhythm guitar lives on this chord.
- How do you play A9 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.
- How do you play A9 on guitar?
- Use the fingering in the diagram above. The fretted notes sit between frets 2 and 5. Strings 3, 2 and 1 ring open.
- What chords work well with A9?
- A9 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.