Package leaflet · Information for the musician · Chord
A Dominant Ninth Chord (A9)
Funky, rich and smooth. A dominant seventh with an added major ninth, less bluesy and more colourful than the plain seventh.
- A9
- 5 notes
- x02423
1Composition: what it contains
A – C♯ – E – G – B
- Symbol
- A9
- Also written
- A9, A7(9), Adom9
- Formula
- 1 3 5 ♭7 9
| Degree | Note | Interval | Semitones |
|---|---|---|---|
| 1 | A | unison | 0 |
| 3 | C♯ | major third | 4 |
| 5 | E | perfect fifth | 7 |
| ♭7 | G | minor seventh | 10 |
| 9 | B | major ninth | 14 |
2Appearance: diagrams and sound
On the guitar
x02423open position
522223fret 2
575657fret 5
x-12-9-12-10-9fret 9
x-12-11-12-12-xfret 11On the ukulele
4130open position
4754fret 4
12-11-9-12fret 9On the piano
On the staff
On bass and as an arpeggio
3Indications: what it is used for
Used on dominant chords in funk, soul, R&B, jazz, gospel and blues. It is the V9 in a ii–V–I, a staple of funk rhythm guitar on one-chord vamps, and the I9 and IV9 chords in jazz blues. It substitutes for any dominant seventh when the melody does not contain the flat ninth. Mixolydian is the typical scale over it. In big-band arrangements it is a common voicing for dominant chords.
4Dosage: how to practise it
On guitar, learn the four-string shape rooted on the fifth string (which omits the fifth) and practise sixteenth-note funk strumming at 90–110 BPM with chord slides from a half step below. On piano, play rootless voicings (3-5-♭7-9 and ♭7-9-3-5) in the left hand. Practise ii9–V9–Imaj9 progressions. Arpeggiate 1-3-5-♭7-9 on bass. Ten minutes daily. Practise a one-chord funk vamp for three minutes, then a twelve-bar blues with all ninth chords, sliding each shape from a fret below.
5Warnings and common mistakes
Do not confuse 9 with add9 (no seventh) or maj9 (major seventh). The symbol '9' alone implies the flat seventh. On guitar, the fifth is usually omitted in ninth voicings; the third and seventh must stay. Avoid playing the ninth in a low register or adjacent to the root at the bottom. If the melody holds the flat ninth (for example in minor keys), use 7♭9 instead.
6Interactions with chords, scales and keys
Inversions
- Inversion 1 · A9/C♯ · C♯ – E – G – B – A
- Inversion 2 · A9/E · E – G – B – A – C♯
- Inversion 3 · A9/G · G – B – A – C♯ – E
- Inversion 4 · A9/B · B – A – C♯ – E – G
Scales to play over A9
7Other presentations available
The same chord from every note
C9 C♯9 D9 E♭9 E9 F9 F♯9 G9 A♭9 B♭9 B9
Other chords on A
A Am Adim Aaug Asus2 Asus4 A5 A6 Am6 A7 Amaj7 Am7 Am7♭5 Adim7 Am(maj7) A7sus4 Aadd9 Am(add9) A6/9 Amaj9 Am9 A11 Am11 A13 A7♭9 A7♯9 A7♯5 A7♭5
Read this leaflet carefully before playing. Keep it near your instrument. Free to use, print and share for personal and educational use.