A7♯9
A Dominant 7th Sharp 9 — major and minor thirds colliding in one chord — gritty, electric, built for emphatic moments.
The keys
A – C♯ – E – G – B♯
What's inside A7♯9
| Note | Interval from root | Degree |
|---|---|---|
| A | Root | 1 |
| C♯ | Major 3rd | 3 |
| E | Perfect 5th | 5 |
| G | Minor 7th | b7 |
| B♯ | Sharp 9th | #9 |
A working voicing
Split the chord between two hands the way working players do — a solid shell low down, the colour tones up top:
| Hand | Keys |
|---|---|
| Left (shell) | A2 – G3 |
| Right (colour) | D♭5 – C6 |
Where A7♯9 lives
Hard resolution
A7♯9 → Dm9
Altered dominants resolve with maximum drama — especially into minor.
Chromatic approach
Em7 → A7♯9 → D
The alteration sharpens the pull of the standard two-five.
Put A7♯9 under your fingers
Hear every voicing, see the keys light up, and drill it in the interactive Chord & Voicing Lab.
Open the Chord & Voicing Lab →