Bb9b5

Bb9b5 is Bb, D, Fb, Ab and C, a nine flat five. The shape this page opens on is written x10110, lowest string first.

Also written Bb9(b5), Bb9-5 or Bb9♭5. The same chord either way; which spelling you meet depends on who wrote the chart.

There are 7 common shapes for Bb9b5 on the guitar, and 27 derived voicings in 2 families.

The common shapes, written lowest string first: x10110, 6x0554, 656556, 6767x8, x78798, x-13-12-13-13-0, x-13-12-13-13-12.

Shell. Root, third and seventh: the guide tones fix the quality, so the fifth is dropped. That is what leaves a string free, so pick a tension to put on top. Bb9b5 has x1011x, 6565xx, xx8798, x-13-12-13-13-x, x1x130, x1015x, 6x675x, 6569xx.

Rootless. The root left to the bass player. Frees a finger for a tension. Bb9b5 has x3213x, xx0110, x5655x, x-x-10-9-9-10, x-x-12-13-13-12, x-15-14-13-15-x, x3x130, xx2534.

Tensions. A shell of Bb9b5, root, third and seventh, leaves a string free, and the tones that belong over it are the b13 (Gb) and the 13 (G).

The common shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.