Am9 A minor ninth chord
- Notes
- A C E G B
- Formula
- 1 b3 5 b7 9
- Semitones
- 0 3 7 10 14 above the root
- Other symbols
- Amin9, A−9
A to C is a minor third (3 semitones), C to E is a major third (4 semitones), E to G is a minor third (3 semitones), G to B is a major third (4 semitones). A minor seventh (Am7) with a major ninth on top: B, 14 semitones above A. The fifth, E, is the note players drop first.
Am9 on the piano
Root position from A4: A4, C5, E5, G5, B5. Middle C is C4.
Am9 on the guitar
Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has A as its lowest note.
5 7 5 5 5 7 (low E to high e)
Sounds A2 E3 G3 C4 E4 B4
x 12 10 12 12 12 (low E to high e)
Sounds A3 C4 G4 B4 E5
The E-shape and A-shape grips are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play minor ninth chords on other roots.
Inversions of Am9
An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.
| Position | Notes, bass first | Named | Listen |
|---|---|---|---|
| Root position | A C E G B | Am9 | |
| 1st inversion | C E G B A | Am9/C | |
| 2nd inversion | E G B A C | Am9/E | |
| 3rd inversion | G B A C E | Am9/G | |
| 4th inversion | B A C E G | Am7/B (also read as Am9/B) |
Where Am9 fits
Am9 is ii9 in G major, vi9 in C major, i9 in A minor. Its upper four notes C E G B are Cmaj7, the usual rootless voicing of Am9 over a A bass.