Abm7b5

General info

Full name

Ab Half-dim 7

Symbol

Abm7b5

Root

Ab

Quality

Half-dim 7

Chord notes

Functions & resolutions

Typical function in key

vii°Leading tone (vii°)A major

Stability / tension

High tension — pulls toward the dominant

Most common resolutions

Db7Db Dominant 7GbmGb Minor

Unstable degrees

2Bb

b3B

resolves down to the 2nd

4Db

b5D

resolves inward to the 4th

4Db

b7Gb

resolves down to the resolution tonic

Main resolution

Abm7b5source

Db7Db Dominant 7

Half-diminished Abm7b5 typically acts as ii in minor, resolving to the dominant (Db7), which then leads to the tonic.

Other resolutions

Abm7b5source

Deceptive resolution

GbmGb Minor

The half-diminished chord can bypass the dominant and resolve directly to the minor tonic — a plagal turn in minor.

Abm7b5source

No resolution needed

In the Locrian mode, a half-diminished chord can function as the tonic, requiring no resolution.

Abm7b5source

Jazz reharmonization

Bm6B Minor 6

In jazz, ø7 is common in ii-V-i progressions but can be substituted with iv6, sharing the same notes.

Abm7b5source

Functional resolution

EE Major

Besides moving to the dominant, the half-diminished chord can resolve to bVI — creating a Phrygian color.

Features

Character

Half-diminished, unstable

Characteristic interval

Diminished 5th (b5)

Description

The diminished fifth creates instability, the minor seventh softens it. Less tense than fully diminished.

Application

• iiø7 in natural minor
• Jazz ii–V in minor
• Unstable predominant sonorities

Voicing & structure

Harmony

Harmonic context

viim7b5A majorDominantiim7b5F# minorPredominantvim7b5B DorianToniciiim7b5E MixolydianTonic

Compatible scales

All chord tones are contained in these scales — use them for improvisation.