Tools / Chords / A♭ 9th

A♭ 9th chord on guitar (A♭9)

Also written A♭9 or A♭

A♭ 9th is built from A♭, C, E♭, G♭, and B♭. This advanced barre chord demands clean fretting across five strings while muting the high E.

3rd fret4-3-4-3-4-×

Positions on the neck1 of 5

How it’s built

A♭1Root

C3Major 3rd

E♭5Perfect 5th

G♭♭7Minor 7th

B♭99th

Formula 1, 3, 5, ♭7, 9

Positions on the neck1 of 5

Inversions

The same three notes, with a different one in the bass.

Root positionA♭–C–E♭–G♭–B♭A♭9Bass A♭

First inversionC–E♭–G♭–B♭–A♭A♭9/CBass C

Second inversionE♭–G♭–B♭–A♭–CA♭9/E♭Bass E♭

Third inversionG♭–B♭–A♭–C–E♭A♭9/G♭Bass G♭

Fourth inversionB♭–A♭–C–E♭–G♭A♭9/B♭Bass B♭

Why it sounds like that

A♭ 9th stacks a major 3rd, perfect 5th, minor 7th, and major 2nd above the root. The minor 7th gives it dominant pull, while the major 2nd adds color. Compare it to the plain A♭ 7th, which omits the 9th.

What goes wrong with A♭ 9th?

Letting the 1st string sound open instead of muting it with the side of the index finger.
Buzzing on the 3rd string because the index barre isn't pressing hard enough.
Allowing the pinky to flatten and deaden the 1st string when fretting the 2nd string.

Changing to and from A♭ 9th

Slide the shape down one fret to the 2nd fret to play G 9th, keeping the same finger pattern.
Move to A 9th by sliding the entire shape up one fret to the 4th fret.

Which voicing to use

The 3rd fret voicing keeps A♭ in the bass for a root-position sound. The A♭9/C inversions put C in the bass, creating a lighter, less grounded feel. Choose the 4th fret voicing for a fuller register.

How do you play an A♭ 9th chord on guitar?

3rd fret

Barre● On the diagram

A♭ 9th is played at the 3rd fret as 4 3 4 3 4 ×: barre your index finger across fret 3, middle finger on the low E string at fret 4, ring finger on the D string at fret 4 and pinky finger on the B string at fret 4. The high e string stays muted.

Tip — The index barre must hold the 5th and 3rd strings at the 3rd fret while the pinky stretches to the 2nd string, 4th fret.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	4	2	A♭ (1)
5 (A)	3	1 (barre)	C (3)
4 (D)	4	3	G♭ (♭7)
3 (G)	3	1 (barre)	B♭ (9)
2 (B)	4	4	E♭ (5)
1 (e)	muted	—	—

4th fret

Barre

A♭ 9th is played at the 4th fret as 4 6 4 5 4 6: barre your index finger across fret 4, ring finger on the A string at fret 6, middle finger on the G string at fret 5 and pinky finger on the high e string at fret 6.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	4	1 (barre)	A♭ (1)
5 (A)	6	3	E♭ (5)
4 (D)	4	1 (barre)	G♭ (♭7)
3 (G)	5	2	C (3)
2 (B)	4	1 (barre)	E♭ (5)
1 (e)	6	4	B♭ (9)

A♭9/C inversion · fret 3

Barre

A♭ 9th is played at the 3rd fret as × 3 4 3 4 4: barre your index finger across fret 3, middle finger on the D string at fret 4, ring finger on the B string at fret 4 and pinky finger on the high e string at fret 4. The low E string stays muted.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	muted	—	—
5 (A)	3	1 (barre)	C (3)
4 (D)	4	2	G♭ (♭7)
3 (G)	3	1 (barre)	B♭ (9)
2 (B)	4	3	E♭ (5)
1 (e)	4	4	A♭ (1)

A♭9/C inversion · fret 6

Barre

A♭ 9th is played at the 6th fret as 8 6 6 8 7 6: barre your index finger across fret 6, ring finger on the low E string at fret 8, pinky finger on the G string at fret 8 and middle finger on the B string at fret 7.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	8	3	C (3)
5 (A)	6	1 (barre)	E♭ (5)
4 (D)	6	1 (barre)	A♭ (1)
3 (G)	8	4	E♭ (5)
2 (B)	7	2	G♭ (♭7)
1 (e)	6	1 (barre)	B♭ (9)

A♭9/C inversion · fret 8

Barre

A♭ 9th is played at the 8th fret as 8 9 8 8 9 8: barre your index finger across fret 8, ring finger on the A string at fret 9 and pinky finger on the B string at fret 9.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	8	1 (barre)	C (3)
5 (A)	9	3	G♭ (♭7)
4 (D)	8	1 (barre)	B♭ (9)
3 (G)	8	1 (barre)	E♭ (5)
2 (B)	9	4	A♭ (1)
1 (e)	8	1 (barre)	C (3)

Common questions

How is A♭ 9th written?

A♭ 9th is written as A♭9 or A♭. On a keyboard, type Ab9. It is also spelled G♯ in enharmonic notation for the same sounding root.

What is the difference between A♭ 9th and A♭ 7th?

A♭ 9th adds the 9th (B♭) to the A♭ 7th chord. The 9th creates a richer, more colorful dominant sound.

Why is the high E string muted in the 3rd fret voicing?

The open high E is not a chord tone in A♭ 9th. Muting it keeps the chord clean and prevents an unwanted note.

Can A♭ 9th be played without a barre?

The 3rd fret voicing requires a barre across five strings. Other inversions also use barres, so this chord is best for players comfortable with barre technique.

String

Fret

Finger

Note

6 (E)

A♭ (1)

5 (A)

1 (barre)

C (3)

4 (D)

G♭ (♭7)

3 (G)

1 (barre)

B♭ (9)

2 (B)

E♭ (5)

1 (e)

muted

—

String

Fret

Finger

Note

6 (E)

1 (barre)

A♭ (1)

5 (A)

E♭ (5)

4 (D)

1 (barre)

G♭ (♭7)

3 (G)

C (3)

2 (B)

1 (barre)

E♭ (5)

1 (e)

B♭ (9)

String

Fret

Finger

Note

6 (E)

muted

—

5 (A)

1 (barre)

C (3)

4 (D)

G♭ (♭7)

3 (G)

1 (barre)

B♭ (9)

2 (B)

E♭ (5)

1 (e)

A♭ (1)

String

Fret

Finger

Note

6 (E)

C (3)

5 (A)

1 (barre)

E♭ (5)

4 (D)

1 (barre)

A♭ (1)

3 (G)

E♭ (5)

2 (B)

G♭ (♭7)

1 (e)

1 (barre)

B♭ (9)

String

Fret

Finger

Note

6 (E)

1 (barre)

C (3)

5 (A)

G♭ (♭7)

4 (D)

1 (barre)

B♭ (9)

3 (G)

1 (barre)

E♭ (5)

2 (B)

A♭ (1)

1 (e)

1 (barre)

C (3)