Ab7b9 guitar chord
Playable, correctly spelled, and not how the chord is normally voiced. Right now this is the shapes that put a ninth, eleventh or thirteenth below the root.
- Tap a note to hear it
- Arrows change position
- Fingers, notes or intervals
- Play the chord
About Ab7b9 — uncommon voicings
Ab7b9 is Ab, C, Eb, Gb and A — Ab9 with the ninth lowered a semitone.
It sounds dark and urgent. The flat ninth comes from the harmonic minor, so this is the V of a minor key rather than a major one.
Altered dominant — it points at a minor chord.
Ab7b9 notes and formula
| Ab | C | Eb | Gb | A |
|---|---|---|---|---|
| 1 | 3 | 5 | ♭7 | ♭9 |
Also written Ab7(b9), Ab7-9 or Ab7♭9. The same chord either way; which spelling you meet depends on who wrote the chart.
How to play Ab7b9
Five notes and four fingers, so something has to go. Keep C and Gb (they fix the quality) and A (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 Ab7b9 as a shell — root, third and seventh — and the spare string takes the #11 (D), the b13 (Fb) or the 13 (F).
All 6 common shapes as fret numbers, lowest string first. Hover or tap one to see it drawn.
- x01112, open position, Bbb, 9th in the bass, top note Gb, barred
- 4342xx, 2nd fret, Ab, root position, top note A, all fretted
- xx4545, 4th fret, Gb, 3rd inversion, top note A, all fretted
- 464545, 4th fret, Ab, root position, top note A, barred
- xx6575, 5th fret, Ab, root position, top note A, all fretted
- x-11-10-11-10-11, 10th fret, Ab, root position, top note Eb, barred
How to use Ab7b9
Ab7b9 is a dominant with its tension raised, so it still points at Db — harder than a plain seventh does, because the altered tones sit a semitone from where they are going.
What to play over Ab7b9
Every note of Ab7b9 is in Ab half-whole diminished.
Each of those is a page: the scale across the neck, and the chords it harmonises into — which is where Ab7b9 sits in it. Every scale.
Chords near Ab7b9
Change one note of Ab7b9 and you have Ab7 (drop the flat ninth), Abalt (the fifth becomes the sharp fifth), Ab9 (the flat ninth becomes the ninth) or Ab7#9 (the flat ninth becomes the sharp ninth).
Ab7b9 is an altered chord — a dominant seventh with its fifth or ninth moved. Altered dominant 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.