Guitar chords in the key of A# or Bb:
Chord Bbmaj7b5 (5th fret) notes: Bb, D, A, D, Fb and A. (Fb=E).
This chord is played by placing a barre on fret five with your index finger.
Bb(A#) major 7 b5 guitar chord's alternative names: Bbmaj7b5, Bbmaj7(b5).
1(A#/Bb), 3(D), b5(E/Fb), 7(A).