Bbmaj7

Bbmaj7 is Bb, D, F and A, a major seventh. The shape this page opens on is written x13231, lowest string first.

Also written BbM7, BbΔ7, BbΔ, Bbma7 or Bb major 7. The same chord either way; which spelling you meet depends on who wrote the chart.

There are 8 common shapes for Bbmaj7 on the guitar, and 36 derived voicings in 4 families.

In which keys. Every note of Bbmaj7 belongs to D minor (the ♭VI), F major (the IV), G minor (the ♭III) and Bb major (the I).

The common shapes, written lowest string first: x13231, xxx335, xx3335, 687766, x-x-8-10-10-10, x-13-12-10-10-10, x-13-12-14-11-x, x-13-15-14-15-13.

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. Bbmaj7 has x102xx, 657xxx, x-13-12-14-x-x, x1x23x, 6x02xx, 6x77xx, x-13-x-14-15-x.

Drop 2. A close-position chord with the second voice from the top lowered an octave. Sits on four adjacent strings. Bbmaj7 has 1102xx, x1323x, xx3335, 5533xx, xx7766, 6877xx, x-x-8-10-10-10, x-12-12-10-11-x.

Drop 3. The third voice from the top lowered an octave. The dropped voice becomes the bass, which is why a string is skipped. Bbmaj7 has x1x231, x5x365, 5x333x, x-8-x-7-10-6, 6x776x, 10-x-8-10-10-x, x-12-x-10-11-10, 13-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. Bbmaj7 has 6x7760, 5x3330, 6570xx, x00060, 5x0060, x00066.

Tensions. A shell of Bbmaj7, root, third and seventh, leaves a string free, and the tones that belong over it are the 9 (C), the #11 (E) 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.