A Suspended 2nd Chord

Chord Tones: A Suspended 2nd Chord

Symbol: sus2 — Formula: 1-2-5

DegreeNoteFrequency (A=440, Equal)
1 A4 440.000 Hz
2 B4 493.883 Hz
5 E4 329.628 Hz

Chord Notation

Notation TypeSymbol / Value
Lead Sheet SymbolAsus2
All Common Symbolssus2
Interval Formula1-2-5
Harmonic Categoryopen

Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.

Inversions

InversionNotes (low to high)Bass NoteSlash Notation
Root Position A4 B4 E4 A A Suspended 2nd Chord
First Inversion B4 E4 A4 B A Suspended 2nd Chord/B
Second Inversion E4 A4 B4 E A Suspended 2nd Chord/E

Harmonic Function

The A sus2 chord commonly functions as the submediant (vi) in C major or dominant (V) in D major. Its harmonic role varies by key — in major keys it provides stable harmonic grounding.

The sus2 chord replaces the third with a major second, creating an open, ambiguous sound with no major or minor quality. It is widely used in rock and pop for its airy, unresolved character. The A Suspended 2nd Chord specifically contains 3 notes: A, B, E (formula: 1-2-5). On guitar, A-rooted chords anchor to the open A string (5th string), and barre chord shapes rooted on A form the basis of the "A-shape" CAGED system. Blues, rock, and country music use A-rooted chords extensively — the classic 12-bar blues often starts on A, and many rock power chord riffs center on the open A string.

Common Progressions

The A Suspended 2nd Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):

Songs Featuring the Suspended 2nd Chord

Well-known songs where the A Suspended 2nd Chord — or this chord type — plays a prominent role:

Tuning Frequencies Across Temperaments

Frequencies shown at A=440 Hz. View full temperament data for any note.

NoteEqual Temp.PythagoreanJust Intonation
A4 440.000 Hz 440.000 Hz 436.043 Hz
B4 493.883 Hz 495.000 Hz 490.548 Hz
E4 329.628 Hz 330.001 Hz 327.032 Hz

Scales Containing the A Suspended 2nd Chord

These scales include the A Suspended 2nd Chord as a diatonic or characteristic chord: