A#/B♭ 13th chords Author: Juan Martinez Categories: A♯ Chords Tags: 13th chords Bb13 chord on a piano Formula: 1-3-5-♭7-9-13 Notes: B♭-D-F-A♭-C-G chord suffix: B♭13 Use these charts to create your own B♭13 chord or play a B♭13 melody. Bb13 chord on a pianoBb 13th chord on a guitar