B♭(♯4) 7-string guitar chord

How to play B♭(♯4) on 7-string guitar

The most common way, the first shape above: your index finger on the A string at the 1st fret, your middle finger on the D string at the 2nd fret, your ring finger on the G string at the 3rd fret and your little finger on the high B string at the 3rd fret. Let the high E string ring open. Don’t play the low B and low E strings.

From the low B string x x 1 2 3 3 0 (x: not played, 0: open)

What notes are in B♭(♯4)?

B♭(♯4), B♭ major with sharp four, no fifth, is B♭, D and E: the root (B♭), the major third (D) and the augmented fourth (E). Its formula is 1 3 ♯4.