Ab9 guitar chord
An open string left ringing against a fretted grip. Because it costs no finger, it sounds a note the closed shape has none left for -- a tension on top, or a pedal root underneath. Either a familiar grip with open strings added, or a shape so sparse the open strings carry the chord. These belong to their key rather than to a shape, so D, A, G and E have many and Eb a handful.
- Tap a note to hear it
- Arrows change position
- Fingers, notes or intervals
- Play the chord
About Ab9 — open string voicings
Ab9 is Ab, C, Eb, Gb and Bb — Ab7 with the ninth stacked on top.
It sounds bright and full, still clearly pulling. The ninth adds height without softening the tritone underneath it, which is why funk and soul comp on this rather than on a plain 7.
Dominant — the same pull as a 7, with more colour.
Ab9 notes and formula
| Ab | C | Eb | Gb | Bb |
|---|---|---|---|---|
| 1 | 3 | 5 | ♭7 | 9 |
Also written Abdom9 or Ab dominant 9. The same chord either way; which spelling you meet depends on who wrote the chart.
How to play Ab9
An open string left ringing against a fretted grip. It costs no finger, so it can sound a note the closed shape has none left for: a tension on top, or a pedal root underneath.
These belong to their key rather than to a shape: they cannot be moved up the neck. D, A, G and E have many; E♭ has a handful.
Ab9 has 2 of them, on strings 5-4-3-2-1 and strings 6-4-3-2-1, from the 3rd fret up to the 5th — every inversion the chord has: C in the bass and Bb in the bass. The one to learn first is the C shape at the 3rd fret, which is the easiest grip here.
Five notes and four fingers, so something has to go. Keep C and Gb (they fix the quality) and Bb (what the symbol is about). Let Eb and Ab go, in that order — a perfect fifth says nothing the root has not, and in a band the bass has the root.
Play Ab9 as a shell — root, third and seventh — and the spare string takes the #11 (D), the b13 (Fb) or the 13 (F).
All 8 common shapes as fret numbers, lowest string first. Hover or tap one to see it drawn.
- x11112, 1st fret, Bb, 9th in the bass, top note Gb, barred
- 411312, 1st fret, Ab, root position, top note Gb, barred
- 4343xx, 3rd fret, Ab, root position, top note Bb, all fretted
- 464346, 3rd fret, Ab, root position, top note Bb, barred
- 464546, 4th fret, Ab, root position, top note Bb, barred
- xx6576, 5th fret, Ab, root position, top note Bb, all fretted
- 8x6876, 6th fret, C, 1st inversion, top note Bb, all fretted
- x-11-10-11-11-11, 10th fret, Ab, root position, top note Eb, barred
How to use Ab9
Ab9 is the V of Db, and that is where it goes if it goes anywhere: the third and the flat seventh are a tritone apart, and both resolve by a semitone into Db.
In which keys. Every note of Ab9 belongs to C# major (the V, the dominant) and Bb minor (the ♭VII).
What to play over Ab9
Every note of Ab9 is in Ab mixolydian and Ab lydian dominant.
Chords near Ab9
Change one note of Ab9 and you have Abmaj9 (the flat seventh becomes the major seventh), Abm9 (the major third becomes the minor third), Abadd9 (drop the flat seventh), Ab69 (the flat seventh becomes the sixth), Ab7 (drop the ninth) or Ab9b5 (the fifth becomes the flat fifth).
Ab9 is a dominant chord — root, major third, fifth, minor seventh. Dominant seventh chords on every root.
The common shapes and the derived voicings come from different places, and both are explained in how this site is built.