A practical way to hear A11 is as held over the original root. The upper shape supplies the flat seventh, ninth, and : A, E, G, B and D.
Because that upper shape omits the dominant’s major third, the chord remains suspended. This bass-plus-shape sound is used mainly as V.
Also written A9sus4 or A dominant 11.
A11 in 2nd inversion puts E in the bass instead of A, the 5th 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 A11’s 15 shapes do this:x7778712-x-12-12-10-x
A11 has the notes of the ii over the V’s root, so it can take the ii’s bar: A11, then A9, then D. The eleventh gives way to the third, and the V resolves as usual.
Listen for: The eleventh falls a half step to the third, then rises a half step into the root of the I.
In which keys. Every note of A11 belongs to C major, D major, E minor, G major, A minor and B minor.
Contains A11 and adds major third and thirteenth.
Contains A11 and adds minor third and flat thirteenth.
Contains A11 and adds minor third 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.