Banjo A♭m chord (Open D)A♭ minor on the 5-string banjo: 1 2 2 1, and 3 more shapes

Frets, string 4 to string 1: 1 2 2 1 (first position)

1. String 4 (D): 1st fret, index finger (barre), E♭
2. String 3 (F♯): 2nd fret, middle finger, A♭
3. String 2 (A): 2nd fret, ring finger, C♭
4. String 1 (D): 1st fret, index finger (barre), E♭
5. String 5, the short f♯: open, F♯, not in the chord

Sounds: E♭ A♭ C♭ E♭  ·  A♭m is A♭, C♭, E♭ (1 · ♭3 · 5)

Found in: B major (vi), B mixolydian (vi), E major (iii), F♯ major (ii), F♯ mixolydian (ii), D♭ mixolydian (v)

The 5th string: the short f♯ adds the ♭7 over A♭m, a colour rather than a clash.

With a capo: on the 1st fret it’s 0 1 1 0 (frets counted from the capo), an open Gm shape. Spike the 5th string at the 6th fret to keep it in tune with the capo.

Open D tuning: f♯DF♯AD, the short 5th string first, then strings 4 to 1.