About the A sharp add nine chord
A sharp add nine is used in A sharp Major, where every note it holds is a scale tone. Think of it as an A♯ added ninth chord.
Its notes are A♯, C♯♯, E♯, and B♯. The intervals are a major third, a perfect fifth, and a major ninth.
Also called add2 and added second. B flat add nine spells the same notes enharmonically.
Inversions
A sharp add nine (root position)
Notes and intervals
| 1 | A#A♯ | Root |
|---|---|---|
| 2 | C##C♯♯ | Major 3rd |
| 3 | E#E♯ | Perfect 5th |
| 4 | B#B♯ | Major 9th |
Shapes
Chromatic
Circle of Fifths
Other A sharp chords
Simpler triads
Suspended
Sixths and sevenths
Extensions
Altered
Functional relationships
These chords are where this one most naturally comes from and resolves to inside a key.
Relative minor
The relative minor uses the same notes and key signature, so it works as a calmer, darker home base.
Parallel minor
The parallel minor keeps the same root note but lowers the third, giving the same key a darker, sadder sound.
Dominant
The dominant is a fifth above the root, and it builds tension that pulls strongly back to this chord.
Subdominant
The subdominant is a fourth above the root (a fifth below), and it usually leads on to the dominant or back home.
Tritone substitution
The tritone substitution stands in for this chord's dominant with a dominant seventh a half step above the root, which slides down by a half step to resolve here.