A♭ Dominant 9th
Also Known As
Hear the A♭ Dominant 9th chord played for you.
A♭9
A♭ – C – E♭ – G♭ – B♭
Formula:R-M3-P5-m7-M9
Intervals:P1-M3-P5-m7-M9
Scale Degrees:1-3-5-b7-9
Introduction
The A♭ Dominant 9th chord is a five-note chord made up of A♭, C, E♭, G♭, and B♭. It is built from a root, major third, perfect fifth, minor seventh, and major ninth.
The Ab Dominant 9th piano chord (Ab9) consists of the notes Ab, C, Eb, Gb, Bb. Formula: R-M3-P5-m7-M9 | Scale degrees: 1-3-5-b7-9.
Notes
Key Signature
The key of Ab Dominant 9th has 4 flats.
B♭E♭A♭D♭
Order of flats
Flats are added in a fixed order — the reverse of the sharp order. Each new flat key adds the next flat on the list.
B♭E♭A♭D♭G♭C♭F♭
Mnemonic: Battle Ends And Down Goes Charles’ Father
Chords in the Key of A♭ Major
These are the diatonic triads built on each degree of the A♭ major scale:
C
D
E
F
G
A
B
C
D
E
F
G
A
B
I — A♭ Major (major)
Theory: Intervals
Formula: R-M3-P5-m7-M9
Intervals: P1-M3-P5-m7-M9
The A♭ Dominant 9th is built by stacking intervals from the root note. The formula R-M3-P5-m7-M9 describes the scale degrees used. The intervals P1-M3-P5-m7-M9 show the distance between each note in the chord.
A♭ Dominant 9th — Frequently Asked Questions
What notes are in the Ab Dominant 9th chord?
The Ab Dominant 9th chord (Ab9) contains 5 notes: Ab, C, Eb, Gb, Bb. Formula: R-M3-P5-m7-M9.
How is Ab9 used in music?
Ab9 is used in jazz, fusion, and contemporary music to add harmonic color. It appears as a dominant or tonic chord depending on context.
What is the scale degree formula for Ab9?
Ab9 uses scale degrees 1-3-5-b7-9, giving it its distinctive sound.
Practice Tips
- Start by placing your thumb on Ab and spacing remaining fingers across the chord.
- Practice Ab9 slowly with separate hands before combining.
- Listen carefully to the tension created by the altered tones in this chord.
- Try voicing Ab9 in different octaves to find the most comfortable position.
- Resolve Ab9 to a nearby chord to hear its function in context.
Related Tools
Chord FinderLook up any chord — see the notes, hear it, and play along.Chord DrillTimed drills to build speed and recognition across all chord types.Practice RoomPlug in a MIDI keyboard and get real-time feedback on every chord and scale.Circle of FifthsVisualize key relationships, relative minors, and key signatures.MIDI MonitorLive MIDI message stream with note names, velocity, and a scrolling staff.