Abmmaj7b5

AbmMaj7b5 is Ab, Cb, D and G, a minor major seven flat five. The shape this page opens on is written 45x433, lowest string first.

Note by note. Ab is the root, Cb is the minor third, D is the flat fifth and G is the major seventh.

Also written AbmM7b5 or Abm(maj7)b5. The same chord either way; which spelling you meet depends on who wrote the chart.

There are 5 common shapes for AbmMaj7b5 on the guitar, and 33 derived voicings in 4 families.

One note away. Change a single note of AbmMaj7b5 and you have Abdim (with one note taken away), Abdim7 (with one note moved), Abmaj7b5 (with one note moved), Abm7b5 (with one note moved) or AbmMaj7 (with one note moved).

The common shapes, written lowest string first: 45x433, 4554x4, xx6787, x-11-x-12-12-10, x-11-12-12-12-x.

Under the hand. None of the shapes for AbmMaj7b5 uses an open string, so every one of them is movable; the lowest sits at the 3rd fret. 2 of the 5 need a barre. Together they cover the neck from the 3rd fret to the 12th.

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. AbmMaj7b5 has 4x543x, x-11-x-12-12-10, 4257xx.

Drop 2. A close-position chord with the second voice from the top lowered an octave. Sits on four adjacent strings. AbmMaj7b5 has xx0103, 3201xx, xx5434, 4554xx, xx6787, x-11-12-12-12-x, x2513x, x5648x.

Drop 3. The third voice from the top lowered an octave. The dropped voice becomes the bass, which is why a string is skipped. AbmMaj7b5 has x2x133, 3x010x, 4x543x, x5x484, 7x678x, x-10-x-7-9-7, 10-x-9-12-9-x, x-11-x-12-12-10.

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. AbmMaj7b5 has 455400, 4x5430, x20020, 340000, x56000, 3x0600.

Tensions. A shell of AbmMaj7b5, root, third and seventh, leaves a string free, and the tones that belong over it are the 11 (Db) and the b13 (Fb).

What kind of chord this is. AbmMaj7b5 is a diminished chord — root, minor third, flat fifth. diminished and half-diminished 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.