Abaug9 guitar chord
The root left to the bass player. Frees a finger for a tension.
- Tap a note to hear it
- Arrows change position
- Fingers, notes or intervals
- Play the chord
About Abaug9 — rootless voicings
Abaug9 is Ab, C, E, Gb and Bb — Ab7 with the fifth raised and the natural ninth added on top.
It sounds bright, tense and slightly unreal. Raising the fifth leaves no semitone in the lower half of the chord, which is where the whole-tone flavour comes from.
Abaug9 notes and formula
| Ab | C | E | Gb | Bb |
|---|---|---|---|---|
| 1 | 3 | ♯5 | ♭7 | 9 |
Altered dominant — dominant pull with a whole-tone colour.
Also written Ab9#5, Ab+9 or Ab9(#5). The same chord either way; which spelling you meet depends on who wrote the chart.
How to play Abaug9
Leave the root to the bass player. In a band nobody misses it, and the ear supplies it from the guide tones anyway.
The finger it frees goes to a tension, which is why these sound richer than the shape they came from rather than thinner.
Abaug9 has 13 of them, on the top four strings, the middle four strings and strings 5-3-2-1, from open position up to the 13th — every inversion the chord has: C in the bass, E in the bass, Gb in the bass and Bb in the bass. The one to learn first is the E shape at the nut, which is the easiest grip here.
5 of them sit on the top four strings, so you can run the inversions up one set without changing strings — which is the whole reason to learn them as a family rather than as separate grips.
Start with xx4556 — no barre and low, at the 4th fret. 1 of the 8 shapes here sits in open position. 5 of the 8 need a barre. Together they cover the neck from the 1st fret to the 14th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| 212112 | 1st fret | Gb, 3rd inversion | Gb | barred |
| 434350 | open position | Ab, root position | E | 1 open string |
| 4x4556 | 4th fret | Ab, root position | Bb | all fretted |
| xx4556 | 4th fret | Gb, 3rd inversion | Bb | all fretted |
| 898998 | 8th fret | C, 1st inversion | C | barred |
| x-11-10-11-11-0 | 10th fret | Ab, root position | Bb | barred |
| x-11-10-11-11-12 | 10th fret | Ab, root position | E | barred |
| 14-13-14-13-13-14 | 13th fret | Gb, 3rd inversion | Gb | barred |
The same notes rebuilt from scratch give 5 shell and 2 open string voicings, each on its own page.
Tensions. A shell of Abaug9, root, third and seventh, leaves a string free, and the tones that belong over it are the #11 (D).
How to use Abaug9
Abaug9 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 Abaug9
Every note of Abaug9 is in Ab whole tone.
Chords near Abaug9
Change one note of Abaug9 and you have Abalt (the ninth becomes a flat ninth), Abaug7 (drop the ninth), Ab9 (the sharp fifth becomes a fifth) or Ab9b5 (the sharp fifth becomes a flat fifth).
Abaug9 is an altered chord — a dominant seventh with its fifth or ninth moved. Altered dominant chords on every root.
On Abaug9’s sound and use this page follows Mark Levine, The Jazz Theory Book (Sher Music, 1995). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.