Banjo B♭7 chord (Double C)B♭ seventh on the 5-string banjo: 2 1 2 3, and 5 more shapes

Frets, string 4 to string 1: 2 1 2 3 (first position) · no root

1. String 4 (C): 2nd fret, middle finger, D
2. String 3 (G): 1st fret, index finger, A♭
3. String 2 (C): 2nd fret, ring finger, D
4. String 1 (D): 3rd fret, little finger, F
5. String 5, the short g: open, G, not in the chord

Sounds: D A♭ D F  ·  B♭7 is B♭, D, F, A♭ (1 · 3 · 5 · ♭7)

The 5th string: the short g rubs against the A♭ in this shape, a semitone away: some players let it ring, some skip it.

Double C tuning: gCGCD, the short 5th string first, then strings 4 to 1.