Bb Dorian

The Bb Dorian mode (also written A#) — Bb C Db Eb F G Ab — shown across the guitar neck.

Also written A# Dorian. A# and Bb are the same pitch, though spelling it from A# would need double accidentals (A# B# C# D# E# F## G#), which is why Bb is the name in use.

Swipe the neck sideways to see the higher frets.

Bb Dorian is the natural minor with one note changed — the 6, G. That single note is what the mode sounds like; lean on it and the colour is obvious, avoid it and you are just playing minor.

The tool shows this from its parent key, Ab major, with Bb marked as where Dorian begins, the same seven notes centered on Ab.