Am7b5

Am7b5 is A, C, Eb and G, a half-diminished seventh. The shape this page opens on is written x0101x, lowest string first.

Also written Aø, Aø7, Am7-5, Am7(b5) or A half diminished. The same chord either way; which spelling you meet depends on who wrote the chart.

There are 9 common shapes for Am7b5 on the guitar, and 29 derived voicings in 3 families.

In which keys. Every note of Am7b5 belongs to G minor (the ii°) and Bb major (the vii°).

The common shapes, written lowest string first: x0101x, xx1213, 5xx543, 5x554x, 567585, xx7888, x-12-10-12-10-11, x-12-13-12-13-x, x-x-13-14-13-15.

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. Am7b5 has x0554x, 5x554x, x-12-x-12-13-11, 5358xx, 5-10-10-8-x-x.

Drop 2. A close-position chord with the second voice from the top lowered an octave. Sits on four adjacent strings. Am7b5 has xx1213, 3312xx, x0101x, xx5545, 5655xx, xx7888, x-10-10-8-10-x, 11-12-10-12-x-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. Am7b5 has 3x121x, x3x243, 5x554x, x6x585, 8x788x, x-10-x-8-10-8, 11-x-10-12-10-x, x-12-x-12-13-11.

Tensions. A shell of Am7b5, root, third and seventh, leaves a string free, and the tones that belong over it are the 11 (D) and the b13 (F).

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