Notes used in A♭ Dominant 9 Chord:A♭ + C + E♭ + G♭ + B♭
Dominant 9 chords are played combining a root, major third, perfect fifth, minor (♭) seventh, and nineth notes of the root note's major scale.
Dominant 9 Chord Formula:1 + 3 + 5 + 7♭ + 9