Db9b5

General info

Full name

Db 9b5

Symbol

Db9b5

Root

Db

Quality

9b5

Chord notes

Functions & resolutions

Typical function in key

IVSubdominant (IV)Ab major

Stability / tension

High tension — requires resolution

Most common resolutions

GbGb MajorEbmEb Minor

Unstable degrees

3F

4Gb

resolves up to the resolution tonic

4Gb

b5G

resolves inward to the resolution tonic

6Bb

b7B

resolves down to the tonic 3rd

Main resolution

Db9b5source

GbGb Major

Dominant 7th Db7 naturally resolves up a 4th to Gb. It is the tritone between the chord's 3rd and 7th that creates this pull.

Other resolutions

Db9b5source

Deceptive resolution

EbmEb Minor

Instead of the tonic, the dominant resolves to the vi degree. Creates surprise and is often used to extend a musical phrase.

Db9b5source

Modal resolution

BB Major

In rock and blues, the dominant often moves to bVII or IV instead of the tonic, creating a modal flavor.

Db9b5source

Jazz reharmonization

G7G Dominant 7

Tritone substitution: Db7 can be replaced by G7 (a tritone away). Both chords share the same tritone between the 3rd and 7th, resolving to the same tonic.

Db9b5source

Functional resolution

Dbsus4Db Sus4

The dominant can resolve beyond the tonic: moving to IV (subdominant) or to a suspension (sus4) are common alternatives in pop and folk music.

Substitutions

Tritone substitution

G7G Dominant 7

Features

Character

Dominant, with 9th and diminished 5th

Characteristic interval

Diminished 5th (b5), 9th

Description

The minor 7th establishes the dominant structure, the 9th extends it, and the diminished 5th adds a second tritone against the root. The chord is more dissonant than a regular 9.

Application

• Tritone sub with ninth
• Jazz and fusion
• Improvising over Lydian dominant

Voicing & structure

Harmony

Compatible scales

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