semicord

Asus4 A suspended fourth chord

Notes
A D E
Formula
1 4 5
Semitones
0 5 7 above the root
Other symbols
Asus

A to D is a perfect fourth (5 semitones), D to E is a major second (2 semitones). The third is replaced by the fourth (D), which wants to fall to the third. With D in the bass the same three keys read as Dsus2.

Asus4 on the piano

C4D4E4F4G4A4B4C5D5E5F5G5A5B5C#4Eb4F#4Ab4Bb4C#5Eb5F#5Ab5Bb5C4AC5DE

Root position from A4: A4, D5, E5. Middle C is C4.

Asus4 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 A as its lowest note.

×AEEAADDE
Open position (A-shape)
x 0 2 2 3 0 (low E to high e)
Sounds A2 E3 A3 D4 E4
5frAAEEAADDEEAA
E-shape barre, root on the E string at fret 5
5 7 7 7 5 5 (low E to high e)
Sounds A2 E3 A3 D4 E4 A4

The barre shapes 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 suspended fourth chords on other roots.

Inversions of Asus4

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 positionA D EAsus4
1st inversionD E ADsus2 (also read as Asus4/D)
2nd inversionE A DE7sus4 (also read as Asus4/E)

Where Asus4 fits

A sus chord has no third, so it is neither major nor minor and has no fixed place in a key. Asus4 usually resolves to A or Am: the fourth, D, falls a half or whole step to the third. Its most common job is Vsus4 in D major, delaying the V chord: Asus4 → A → D.