The A♭ Minor 9th chord is a five-note chord made up of A♭, C♭, E♭, G♭, and B♭. It is built from a root, minor third, perfect fifth, minor seventh, and major ninth.
Construction
A♭ Minor 9th = Root + Minor 3rd + Perfect 5th + Minor 7th + Major 2nd = A♭ · C♭ · E♭ · G♭ · B♭
| Note | Interval | Degree |
|---|---|---|
| A♭ | Root | 1 |
| C♭ | Minor 3rd | ♭3 |
| E♭ | Perfect 5th | 5 |
| G♭ | Minor 7th | ♭7 |
| B♭ | Major 2nd | 9 |
Key Signature
A chord has no key signature of its own, but the A♭ Minor 9th is the tonic (i) chord of Ab Minor, which shares the signature of its relative major, Cb Major — 7 flats (B♭, E♭, A♭, D♭, G♭, C♭, F♭).
B♭E♭A♭D♭G♭C♭F♭
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♭ Minor
These are the triads built on each degree of the A♭ minor scale:
A♭ Minor 9th — Frequently Asked Questions
What is the A♭ Minor 9th chord on piano?
The A♭ Minor 9th chord contains the notes A♭ – C♭ – E♭ – G♭ – B♭. On piano, play these notes together to sound the chord.
What notes are in the Ab Minor 9th chord?
The Ab Minor 9th chord (Abm9) contains five notes: Ab (root), Cb (minor third, enharmonically B), Eb (perfect fifth), Gb (minor seventh), and Bb (major ninth). It is Abm7 with an added ninth.
How does Abm9 differ from Ab9?
Abm9 has a minor third (Cb). Ab9 has a major third (C). Abm9 is dark; Ab9 is dominant.
How is Abm9 used in music?
Abm9 is the ii in Gb Major (Abm9–Db13–Gbmaj9). It appears in jazz, neo-soul, and R&B.
What songs use Minor 9th chords?
Minor 9th chords define neo-soul and lo-fi music.
How does Abm9 differ from Abm7?
Abm9 adds the ninth (Bb) for richer colour.
Do I need to play all five notes?
No — drop the fifth: Ab–Cb–Gb–Bb is practical.