A♭ 7th flat 5 chord on bass (A♭7♭5)

Also called or written A♭7♭5, A♭, A♭ Dominant 7th Flat 5 or A♭ 7th ♭5

A♭ 7th flat 5 contains A♭, C, E♭♭ and G♭. The 4th-fret shape is low on the neck, where the frets are wider and the stretch is more demanding.

4frA♭E♭♭G♭CEADG
Positions on the neck1 of 3
Practice A♭ 7th flat 5 chord

How it is built

A♭RootCMajor thirdE♭♭Diminished fifthG♭Minor seventh

Formula 1, 3, ♭5, ♭7

Inversions

How do you play an A♭ 7th flat 5 chord on bass?

A♭ 7th flat 5 is played at the 4th fret as 4 5 4 5: index finger on the E string at fret 4, ring finger on the A string at fret 5, middle finger on the D string at fret 4 and pinky finger on the G string at fret 5.

Full note and interval breakdown
StringFretFingerNote
4 (E)41A♭ (1)
3 (A)53E♭♭ (♭5)
2 (D)42G♭ (♭7)
1 (G)54C (3)

AdvancedThe 4th-fret shape requires the pinky to reach fret 5 on the 1st string while the index holds fret 4 on the 4th string, stretching the left hand.

A♭7♭5/E♭♭ inversion

A♭ 7th flat 5 is played at the 10th fret as 10 11 10 11: index finger on the E string at fret 10, ring finger on the A string at fret 11, middle finger on the D string at fret 10 and pinky finger on the G string at fret 11.

Full note and interval breakdown
StringFretFingerNote
4 (E)101E♭♭ (♭5)
3 (A)113A♭ (1)
2 (D)102C (3)
1 (G)114G♭ (♭7)

A♭7♭5/G♭ inversion

A♭ 7th flat 5 is played in open position as 2 3 0 1: middle finger on the E string at fret 2, ring finger on the A string at fret 3 and index finger on the G string at fret 1. The D string rings open.

Full note and interval breakdown
StringFretFingerNote
4 (E)22G♭ (♭7)
3 (A)33C (3)
2 (D)openE♭♭ (♭5)
1 (G)11A♭ (1)

Why it sounds like that

A♭ 7th flat 5 is built from the formula 1, 3, ♭5, ♭7. The diminished 5th between A♭ and E♭♭ defines its unstable quality. Compare it with A♭ 7th, which has a perfect 5th.

What goes wrong with A♭ 7th flat 5?

  • Letting the pinky collapse on the 1st string, which mutes the G♭ at fret 5.
  • Pressing the ring finger too flat on the 3rd string, so it deadens the 2nd string next to it.
  • Striking the open 5th string, which is not part of the chord and adds an unwanted A♭.

When to use it

Use the supplied linked chords to hear its tension without adding unsupported harmony. It can substitute for A♭ 7th when the ♭5 is needed. Its tense sound fits bebop and fusion lines.

Changing to and from A♭ 7th flat 5

  • Move to F♯ 7th flat 5 by sliding the shape down two frets to the 2nd fret.
  • Move to A 7th flat 5 by sliding the shape up one fret to the 5th fret.

Which voicing to use

The 4th-fret shape keeps A♭ in the bass for a root-position sound. The A♭7♭5/D inversion at fret 10 puts the ♭5 in the bass, and the A♭7♭5/F♯ inversion at fret 2 puts the ♭7 in the bass, creating a darker, less stable feel.

Other A♭ chords

Common questions

How is A♭ 7th flat 5 written?

A♭ 7th flat 5 is written A♭7♭5 or Ab7♭5. The symbol A♭ is also used, and the chord is sometimes called Dominant 7th Flat 5. It is also spelled G♯ in enharmonic notation for the same sounding root.

What is the difference between A♭7♭5 and A♭7?

A♭7♭5 has a diminished 5th (E♭♭) instead of the perfect 5th (E♭) in A♭7. That one note changes the chord from bluesy to tense and unresolved.

Can A♭7♭5 be used in place of A♭7?

A♭7♭5 can replace A♭7 when the melody or solo uses the ♭5. In a standard blues, the ♭5 may clash with the expected perfect 5th, so use it selectively.