Ab9 Chord
Ab9 is a dominant seventh plus B flat, the ninth. Its full spelling has five different notes, so a practical guitar or ukulele grip may leave out a less essential chord tone.
- Notes: A flat-C-E flat-G flat-B flat
- Symbol: Ab9
- V9 in Db major
- Seventh and ninth
Ab9
How to play an Ab9 chord
Notes: Ab - C - Eb - Gb - BbAb9
Root position
Ab - C - Eb - Gb - Bb1st inversion
C - Eb - Gb - Bb - Ab2nd inversion
Eb - Gb - Bb - Ab - C3rd inversion
Gb - Bb - Ab - C - Eb
Where does Ab9 belong?
In Db major, Ab9 extends the V7 chord before it resolves to the tonic.
Play the role cards to hear how its surrounding chords change the job it does; Diatonic Chords explains the basic numbered roles.
- Dominant with a ninthV9
A V7 with the ninth on top: the same pull to Db, a fuller sound.
DbGbAb9V9Db - Funk and blues homeI9
In funk and blues this is a home chord that never has to resolve.
Ab9I9Db9Ab9Eb9
Progressions to try
- DbGbAb9Db
Ab9 is V9 in Db major; its seventh keeps the dominant pull while the ninth adds another voice.
- Ab9Db9Ab9Eb9
Treat the repeated Ab9 as a blues home chord, then hear the other ninth chords answer it.
Which shape should you use?
On guitar, start with 464546, a barre at the 4th fret.
On ukulele, the open shape 1021 is the easiest place to start. 3643 gives a higher version.
On piano, spread the five-note spelling across both hands: A flat-C-E flat-G flat-B flat. Move A flat up an octave to reach the first inversion, C-E flat-G flat-B flat-A flat; the notes remain the same while the lowest voice changes.
What are the inversions?
The first four notes, A flat-C-E flat-G flat, form the dominant seventh. B flat adds the ninth.
- Root position: A flat-C-E flat-G flat-B flat, with A flat lowest.
- First inversion: C-E flat-G flat-B flat-A flat, written Ab9/C if C is lowest in the whole arrangement.
- Second inversion: E flat-G flat-B flat-A flat-C, written Ab9/Eb if E flat is lowest in the whole arrangement.
- Third inversion: G flat-B flat-A flat-C-E flat, written Ab9/Gb if G flat is lowest in the whole arrangement.
- Fourth inversion: B flat-A flat-C-E flat-G flat, written Ab9/Bb if B flat is lowest in the whole arrangement.
A slash chord names the note in the bass, not merely the lowest note under one hand. Chord Inversions shows how to read that distinction.
How does Ab9 differ from Ab7?
Remove the ninth, B flat, and the remaining notes form Ab7. The seventh stays, so both chords can still pull toward the same tonic. Try that one-note change on piano, then use the comparer to hear it in the full chord. See Ab7 for the other chord's full spelling and roles.
Ab9
Ab - C - Eb - Gb - BbAb7
Ab - C - Eb - Gb