About Abm — triad voicings
Abm is Ab, Cb and Eb — Ab with the third lowered a semitone.
It sounds darker than a major triad, and just as settled. The i of a minor key, and the vi, ii or iii of a major one.
Abm notes and formula
| Ab | Cb | Eb |
|---|---|---|
| 1 | ♭3 | 5 |
Tonic — minor chords rest as readily as major ones.
Also written Abmin, Ab- or Ab minor. The same chord either way; which spelling you meet depends on who wrote the chart.
How to play Abm
Three notes on one string set. No seventh, so nothing is claimed about the chord beyond its quality.
Thin on their own, excellent over a bass line or against someone else’s harmony.
Abm has 45 of them, on the low-middle three, the high-middle three, the middle four strings, the top three strings, the top four strings, the bottom four strings, the bottom three strings, strings 6-4-3-2 and strings 5-3-2-1, from open position up to the 13th — every inversion the chord has: Ab in the bass, Cb in the bass and Eb in the bass. The one to learn first is the Cb shape at the nut, which is the easiest grip here.
6 of them sit on the middle four strings, 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 4211x4 — no barre and down at the nut. None of the shapes for Abm uses an open string, so every one of them is movable; the lowest sits at the 1st fret. 2 of the 8 need a barre. Together they cover the neck from the 1st fret to the 14th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| 4211x4 | 1st fret | Ab, root position | Ab | all fretted |
| 466444 | 4th fret | Ab, root position | Ab | barred |
| xx6444 | 4th fret | Ab, root position | Ab | barred |
| xx6897 | 6th fret | Ab, root position | Cb | all fretted |
| xx9897 | 7th fret | Cb, 1st inversion | Cb | all fretted |
| x-11-9-8-9-x | 8th fret | Ab, root position | Ab | all fretted |
| x-11-13-13-12-11 | 11th fret | Ab, root position | Eb | all fretted |
| x-14-13-13-12-x | 12th fret | Cb, 1st inversion | Cb | all fretted |
How to use Abm
How you get to it. The turn that lands on Abm is Bbm7♭5 to Eb7♭9: the ii and the V of Ab minor, which is where a minor tonic is usually arrived at rather than simply begun on.
In which keys. Every note of Abm belongs to C# minor (the v), Eb minor (the iv), E major (the iii), F# major (the ii), Ab minor (the i) and B major (the vi).
What to play over Abm
Every note of Abm is in Ab minor pentatonic, Ab blues, Ab dorian, Ab natural minor and Ab phrygian.
Chords near Abm
Change one note of Abm and you have Ab (the minor third becomes a major third), Abdim (the fifth becomes a flat fifth), Absus2 (the minor third becomes a ninth), Absus4 (the minor third becomes a fourth), Abm6 (add the sixth) or Abm7 (add the flat seventh).
Abm is a minor chord — root, minor third, fifth. Minor chords on every root.
On Abm’s sound and use this page follows Edward Aldwell & Carl Schachter, Harmony and Voice Leading (Schirmer / Cengage, 4th ed., 2011). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.