Dominant family
A dominant ninth chord
A9A dominant ninth
Piano root position
- Root
- 3
- 5
- ♭7
- 9
Guitar standard tuning
Barre · fret 5
Lay your index flat across strings 6 to 2 at fret 5.
Finger: 1 index, 2 middle, 3 ring, 4 little
Notation treble clef
Intervals
12 semitones- A1
- ♭2
- B9
- ♭3
- C♯3
- 4
- ♭5
- E5
- ♯5
- 6
- G♭7
- 7
- A Root
- C♯ Major 3rd
- E Perfect 5th
- G Minor 7th
- B Major 9th
About this chord
What is an A dominant ninth chord?
A9 is built from 5 notes: A (the root), C♯ (the 3), E (the 5), G (the ♭7), B (the 9). The dominant seventh with a ninth: funky and full.
- Notes
- A · C♯ · E · G · B
- Formula
- 1 · 3 · 5 · ♭7 · 9
- Also written
- Adom9
- Found in
- Outside the major and minor keys
Neighbours
Chords close to A9
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All 348 chords
Every chord type on every root, each with its own page.
C
D♭
D
E♭
E
F
G♭
G
A♭
A
B♭