Abmaj9 is Ab, C, Eb, G and Bb. It keeps every note of and adds the .
Abmaj9 can fill the same major-tonic role as , with both the major 7th and 9th.
Abmaj9 and both contain the 9th; only Abmaj9 contains .
Hear the 9th by comparing with Abmaj9.
One repeated root rises two frets to the 9th. Every other note stays the same.
Also written AbM9, AbΔ9, Abma9 or Ab major 9.
Abmaj9 in 3rd inversion puts G in the bass instead of Ab, the 7th of the chord. The notes are the same; what changes is what the bass line does, which is most of why you would reach for it — it lets the lowest voice move by step where the root would have jumped.
2 of Abmaj9’s 11 shapes do this:3x131xxx5546
At the end of a jazz ii–V–I, Abmaj9 is the usual landing rather than a bare major seventh. The top voice that was the ii’s ninth and the V’s thirteenth steps down onto the ninth.
Listen for: The top voice holds through the ii and V, then falls a whole step to the ninth. On the maj7 it stays where it is, as the third.
A minor-key tune can cadence on Abmaj9 instead of the i, a softer landing a step below Bb. The ♭VII’s root doesn’t move: it becomes the ninth.
Listen for: The root of the ♭VII holds as the ninth while the other voices step. On the maj7 it has to fall a whole step to the root.
Heard in“Eight Miles High”“You Showed Me”
In which keys. Every note of Abmaj9 belongs to C minor, Eb major, F minor and Ab major.
Contains Abmaj9 and adds eleventh and thirteenth.
Contains Abmaj9 and adds sharp eleventh and thirteenth.
The common shapes and the derived voicings come from different places, and both are explained in how this site is built.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.