Gb9

General info

Full name

Gb 9th

Symbol

Gb9

Root

Gb

Quality

9th

Chord notes

Functions & resolutions

Typical function in key

IVSubdominant (IV)C# major

Stability / tension

High tension — requires resolution

Most common resolutions

BB MajorAbmAb Minor

Unstable degrees

3Bb

4B

resolves up to the resolution tonic

6Eb

b7E

resolves down to the tonic 3rd

Main resolution

Gb9source

BB Major

Dominant 7th Gb7 naturally resolves up a 4th to B. It is the tritone between the chord's 3rd and 7th that creates this pull.

Other resolutions

Gb9source

Deceptive resolution

G#mG# Minor

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

Gb9source

Modal resolution

EE Major

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

Gb9source

Jazz reharmonization

C7C Dominant 7

Tritone substitution: Gb7 can be replaced by C7 (a tritone away). Both chords share the same tritone between the 3rd and 7th, resolving to the same tonic.

Gb9source

Functional resolution

Gbsus4Gb 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

C7C Dominant 7

Features

Character

Dominant, with a minor 7th and major 9th

Characteristic interval

9th

Description

The major 3rd and minor 7th form a dominant core, while the major 9th adds a diatonic extension. The dominant tritone preserves directed tension toward resolution.

Application

• V9–I in jazz
• Funk and soul
• Blues harmony

Voicing & structure

Harmony

Compatible scales

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