Abdim7 guitar chord
An open string left ringing against a fretted grip. Because it costs no finger, it sounds a note the closed shape has none left for -- a tension on top, or a pedal root underneath. Either a familiar grip with open strings added, or a shape so sparse the open strings carry the chord. These belong to their key rather than to a shape, so D, A, G and E have many and Eb a handful.
- Tap a note to hear it
- Arrows change position
- Fingers, notes or intervals
- Play the chord
About Abdim7 — open string voicings
Abdim7 is Ab, Cb, D and F — Abdim with a diminished seventh stacked on top.
It sounds suspenseful and rootless. Three stacked minor thirds divide the octave evenly, so the same four notes spell four dim7 chords and the shape repeats every three frets.
Abdim7 notes and formula
| Ab | Cb | D | F |
|---|---|---|---|
| 1 | ♭3 | ♭5 | ♭♭7 |
Leading-tone or passing chord — it can resolve almost anywhere.
Also written Ab°7, Abo7 or Ab diminished 7. The same chord either way; which spelling you meet depends on who wrote the chart.
How to play Abdim7
An open string left ringing against a fretted grip. It costs no finger, so it can sound a note the closed shape has none left for: a tension on top, or a pedal root underneath.
These belong to their key rather than to a shape: they cannot be moved up the neck. D, A, G and E have many; E♭ has a handful.
Abdim7 has 6 of them, on strings 6-5-4-3-2-1, strings 6-4-3-2-1 and strings 5-4-3-2-1, from the 3rd fret up to the 6th — every inversion the chord has: Ab in the bass, Cb in the bass and Ebb in the bass. The one to learn first is the Ab shape at the 3rd fret, which is the easiest grip here.
3 of them sit on strings 6-4-3-2-1, so you can run the inversions up one set without changing strings — which is the whole reason to learn them as a family rather than as separate grips.
Start with xx0101 — no barre and 2 open strings. 1 of the 7 shapes here sits in open position. 2 of the 7 need a barre. Together they cover the neck from the 1st fret to the 13th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| xx0101 | open position | Ebb, 2nd inversion | F | 2 open strings |
| 4x3434 | 3rd fret | Ab, root position | Ab | barred |
| 456464 | 4th fret | Ab, root position | Ab | barred |
| xx6767 | 6th fret | Ab, root position | Cb | all fretted |
| x-x-9-10-9-10 | 9th fret | Cb, 1st inversion | D | all fretted |
| x-11-12-10-12-10 | 10th fret | Ab, root position | D | all fretted |
| x-x-12-13-12-13 | 12th fret | Ebb, 2nd inversion | F | all fretted |
The same notes rebuilt from scratch give 4 shell, 15 drop 2 and 10 drop 3 voicings, each on its own page.
Tensions. A shell of Abdim7, root, third and seventh, leaves a string free, and the tones that belong over it are the 9 (Bb), the 11 (Db), the b13 (Fb) and the maj7 (G).
How to use Abdim7
A diminished seventh divides the octave evenly, so Abdim7 has no single root and no single destination: it can lead to Db or to A, and it is the same four notes either way.
What to play over Abdim7
Every note of Abdim7 is in Ab diminished and Ab half-whole diminished.
Chords near Abdim7
Change one note of Abdim7 and you have Abdim (drop the sixth), Abm6 (the flat fifth becomes a fifth), Abm7b5 (the sixth becomes a flat seventh) or AbmMaj7b5 (the sixth becomes a major seventh).
Abdim7 is a diminished chord — root, minor third, flat fifth. Diminished and half-diminished chords on every root.
On Abdim7’s sound and use this page follows Stefan Kostka, Dorothy Payne & Byron Almén, Tonal Harmony (McGraw-Hill, 8th ed., 2018). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.