Bbmaj7b5

Bbmaj7b5 is Bb, D, Fb and A, a major seven flat five. The shape this page opens on is written x1223x, lowest string first.

Note by note. Bb is the root, D is the major third, Fb is the flat fifth and A is the major seventh.

Also written BbM7b5, BbΔ7b5 or Bbmaj7(b5). The same chord either way; which spelling you meet depends on who wrote the chart.

There are 7 common shapes for Bbmaj7b5 on the guitar, and 36 derived voicings in 4 families.

One note away. Change a single note of Bbmaj7b5 and you have Bbmaj7 (with one note moved), Bbmaj7#5 (with one note moved), BbmMaj7b5 (with one note moved) or Bb7b5 (with one note moved).

In which keys. Every note of Bbmaj7b5 belongs to D minor (the ♭VI) and F major (the IV).

The common shapes, written lowest string first: x1223x, 657755, 6777x0, 6777x6, x-x-8-9-10-10, x-13-12-14-15-12, x-13-14-14-15-x.

Under the hand. None of the shapes for Bbmaj7b5 uses an open string, so every one of them is movable; the lowest sits at the 1st fret. 3 of the 7 need a barre. Together they cover the neck from the 1st fret to the 15th.

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. Bbmaj7b5 has x1x230, x1025x, 6x025x, 6x775x, 6579xx, x-13-x-14-15-12, x-x-8-7-10-12.

Drop 2. A close-position chord with the second voice from the top lowered an octave. Sits on four adjacent strings. Bbmaj7b5 has 0102xx, x1223x, xx7756, 6777xx, x-x-8-9-10-10, 12-13-12-14-x-x, x-13-14-14-15-x, xx2335.

Drop 3. The third voice from the top lowered an octave. The dropped voice becomes the bass, which is why a string is skipped. Bbmaj7b5 has x1x230, 5x233x, x5x355, 6x775x, x-7-x-7-10-6, 10-x-8-9-10-x, x-12-x-9-11-10, 12-x-12-14-11-x.

Open string. An open string left ringing against a fretted grip. Because it costs no finger, it sounds a note the closed shape has none left for -- a tension on top, or a pedal root underneath. Either a familiar grip with open strings added, or a shape so sparse the open strings carry the chord. These belong to their key rather than to a shape, so D, A, G and E have many and Eb a handful. Bbmaj7b5 has x00056, 000036, 00005x, xx0055, x0203x, 0570xx.

Tensions. A shell of Bbmaj7b5, root, third and seventh, leaves a string free, and the tones that belong over it are the 9 (C) and the 13 (G).

What kind of chord this is. Bbmaj7b5 is a major chord — root, major third, fifth. major chords on every root, and what they are for.

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