Ab7sus4

Ab7sus4 is Ab, Db, Eb and Gb, a dominant seventh suspended fourth. The shape this page opens on is written xxx122, lowest string first.

Also written Ab7sus or Ab dominant 7 sus 4. The same chord either way; which spelling you meet depends on who wrote the chart.

There are 7 common shapes for Ab7sus4 on the guitar, and 27 derived voicings in 3 families.

In which keys. Every note of Ab7sus4 belongs to C# major (the V), C# minor (the v), Eb minor (the iv), E major (the iii), F# major (the ii), Ab minor (the i), Bb minor (the ♭VII) and B major (the vi).

The common shapes, written lowest string first: xxx122, xx1122, 464644, xx6879, x-11-11-11-9-9, x-11-13-11-14-11, x-x-13-13-14-14.

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. Ab7sus4 has 444xxx, x-11-11-11-x-x, 4x46xx, x-11-x-11-14-x, x-11-x-6-7-x.

Drop 2. A close-position chord with the second voice from the top lowered an octave. Sits on four adjacent strings. Ab7sus4 has xx1122, xx4644, 4646xx, x6667x, x-x-11-11-9-11, 11-11-11-11-x-x, x-x-13-13-14-14, 2411xx.

Drop 3. The third voice from the top lowered an octave. The dropped voice becomes the bass, which is why a string is skipped. Ab7sus4 has x4x142, 2x112x, x6x674, 4x464x, 9x687x, x9x899, 11-x-11-11-9-x, x-11-x-11-14-11.

Tensions. A shell of Ab7sus4, root, third and seventh, leaves a string free, and the tones that belong over it are the 9 (Bb) and the 13 (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.