Abadd9 Ab major add nine chord
- Notes
- Ab C Eb Bb
- Formula
- 1 3 5 9
- Semitones
- 0 4 7 14 above the root
- Also written
- G#add9 (G# B# D# A#)
- Other symbols
- Ab(add9), Abadd2
Ab to C is a major third (4 semitones), C to Eb is a minor third (3 semitones), Eb to Bb is a perfect fifth (7 semitones). A major triad with the ninth, Bb, added and no seventh. The ninth is the second of the scale an octave up, so with Bb played right next to the root the same chord is often written Abadd2. It is not Absus2: the third C is still there.
Abadd9 on the piano
Root position from Ab4: Ab4, C5, Eb5, Bb5. Middle C is C4.
Abadd9 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 Ab as its lowest note.
4 3 x 3 4 x (low E to high e)
Sounds Ab2 C3 Bb3 Eb4
x 11 10 x 11 11 (low E to high e)
Sounds Ab3 C4 Bb4 Eb5
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 major add nine chords on other roots.
Inversions of Abadd9
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 | Ab C Eb Bb | Abadd9 | |
| 1st inversion | C Eb Bb Ab | Abadd9/C | |
| 2nd inversion | Eb Bb Ab C | Abadd9/Eb | |
| 3rd inversion | Bb Ab C Eb | Ab/Bb (also read as Abadd9/Bb) |
Where Abadd9 fits
Abadd9 is I in Ab major, IV in Eb major, V in Db major. The added Bb belongs to all three of those keys, so Abadd9 can stand in for Ab wherever it appears; it keeps the major sound but softens it. It is not a substitute for Ab9, which also has the seventh Gb.