semicord

Ab7sus4 Ab seventh suspended fourth chord

Notes
Ab Db Eb Gb
Formula
1 4 5 b7
Semitones
0 5 7 10 above the root
Also written
G#7sus4 (G# C# D# F#)
Other symbols
Ab7sus

Ab to Db is a perfect fourth (5 semitones), Db to Eb is a major second (2 semitones), Eb to Gb is a minor third (3 semitones). A dominant seventh with the fourth, Db, in place of the third. Like any sus chord it is neither major nor minor. With Gb in the bass the same four keys read as Ab7sus4/Gb.

Ab7sus4 on the piano

C4D4E4F4G4A4B4C5D5E5F5G5A5B5C#4Eb4F#4Ab4Bb4Db5Eb5Gb5Ab5Bb5C4AbC5DbEbGb

Root position from Ab4: Ab4, Db5, Eb5, Gb5. Middle C is C4.

Ab7sus4 on the guitar

Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has Ab as its lowest note.

4frAbAbEbEbGbGbDbDbEbEbAbAb
E-shape barre, root on the E string at fret 4
4 6 4 6 4 4 (low E to high e)
Sounds Ab2 Eb3 Gb3 Db4 Eb4 Ab4
11fr×AbAbEbEbGbGbDbDbEbEb
A-shape barre, root on the A string at fret 11
x 11 13 11 14 11 (low E to high e)
Sounds Ab3 Eb4 Gb4 Db5 Eb5

The E-shape and A-shape grips are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play seventh suspended fourth chords on other roots.

Inversions of Ab7sus4

An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.

PositionNotes, bass firstNamedListen
Root positionAb Db Eb GbAb7sus4
1st inversionDb Eb Gb AbAb7sus4/Db
2nd inversionEb Gb Ab DbEbm11 (also read as Ab7sus4/Eb)
3rd inversionGb Ab Db EbAb7sus4/Gb

Where Ab7sus4 fits

Ab7sus4 is V7sus4 in Db major. The usual move is Ab7sus4 → Ab7: the fourth, Db, falls a half step to the third C while the seventh Gb stays. In modal jazz and gospel it is often left unresolved.