Finger Positions

Root Note A

Name A suspended fourth over C#

Intervals 1P-4P-5P

Relative Minor F#m

Notes C#, A, D, E

Aliases Asus4, Asus

How to play the Asus4/C# Chord

The Asus4/C# is a fundamental suspended chord in guitar music. To play this chord correctly, ensure your fingers are placed precisely on the frets indicated in the diagram above.

Music Theory Analysis

From a theoretical perspective, the A suspended fourth over C# is built using the 1P, 4P, 5P intervals. In the key of A Major, this chord functions as the I chord.

Common Progressions

In music composition, the Asus4/C# chord is often used to create tension or resolution.

I-V-vi-IV

A → E → F#m → D

vi-IV-I-V

F#m → D → A → E

The Diatonic Family

Understanding the "family" of chords that belong to A helps with transposition and ear training.

Triads

A Bm C#m D E F#m G#dim

7ths

Amaj7 Bm7 C#m7 Dmaj7 E7 F#m7 G#m7b5

Scale Compatibility

View All Scales

Major Minor Minor Blues Melodic Minor Harmonic Minor Bebop Dorian Mixolydian Phrygian Ionian Pentatonic Mixolydian Pentatonic Ritusen Egyptian Vietnamese 1 Kumoijoshi

* 15 scales found containing the notes C#, A, D, E.

Acoustic & Digital Analysis

Digital footprint of the Asus4/C# chord for MIDI programming and synthesizer sound design.

MIDI Numbers 61, 69, 62, 64

Frequencies (Hz)

277.1826309768721, 440, 293.6647679174076, 329.6275569128699