A Suspended Fourth Chord (Asus4)

1Composition: what it contains

A – D – E

Symbol

Asus4

Also written

Asus4, Asus

Formula

1 4 5

2Appearance: diagrams and sound

On the guitar

On the ukulele

On the piano

On the staff

On bass and as an arpeggio

3Indications: what it is used for

In classical harmony it is a suspension: the fourth is held over from the previous chord and then resolves down to the third (4–3 suspension), very common on the V chord at cadences (Vsus4–V–I). In pop, rock and folk it is used as a colour chord and in strummed patterns (major–sus4–major). In gospel and jazz it appears as a 'sus' dominant, often extended to 7sus4 or 9sus4. It suits anthems, worship songs and open-string guitar riffs.

4Dosage: how to practise it

On guitar, practise the open shapes and hammer the fourth on and off while strumming; then learn barre shapes rooted on the fifth and sixth strings. On piano, play root–fourth–fifth and resolve the fourth down to the third, both hands, at 60 BPM. Practise the cadence IV–Vsus4–V–I in several keys. Spend five minutes a day writing short chord loops using sus4 resolutions to train both hands and ear. On bass, outline root, fourth and fifth, then move the fourth to the third when the chord resolves.

5Warnings and common mistakes

Do not play the third together with the fourth unless you want a dense add11 sound: the 'sus' chord means no third. 'Sus' alone usually means sus4. Do not confuse it with an eleventh chord, which also contains a seventh and often a ninth. On guitar, check that your finger is not muting the fourth when it should ring. A sus4 does not have to resolve in modern styles, but in classical writing it should.

6Interactions with chords, scales and keys

Inversions

• Inversion 1 · Asus4/D · D – E – A Play
• Inversion 2 · Asus4/E · E – A – D Play

Scales to play over Asus4

• A Major Scale
• A Natural Minor Scale
• A Harmonic Minor Scale
• A Melodic Minor Scale
• A Dorian Mode
• A Phrygian Mode
• A Mixolydian Mode
• A Minor Pentatonic Scale
• A Blues Scale
• A Phrygian Dominant Scale
• A Double Harmonic Major Scale
• A Bebop Dominant Scale

7Other presentations available

The same chord from every note

Csus4 C♯sus4 Dsus4 E♭sus4 Esus4 Fsus4 F♯sus4 Gsus4 A♭sus4 B♭sus4 Bsus4

Other chords on A

A Am Adim Aaug Asus2 A5 A6 Am6 A7 Amaj7 Am7 Am7♭5 Adim7 Am(maj7) A7sus4 Aadd9 Am(add9) A6/9 A9 Amaj9 Am9 A11 Am11 A13 A7♭9 A7♯9 A7♯5 A7♭5