Finger Positions

Root Note C#

Name C# diminished seventh over A#

Intervals 1P-3m-5d-7d

Relative Minor A#m

Notes A#, C#, E, G, Bb

Aliases C#dim7, C#°7, C#o7

How to play the C#dim7/A# Chord

The C#dim7/A# is a fundamental dominant 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 C# diminished seventh over A# is built using the 1P, 3m, 5d, 7d intervals. In the key of C# Major, this chord functions as the I chord.

Common Progressions

In music composition, the C#dim7/A# chord is often used to create tension or resolution.

I-V-vi-IV

C# → G# → A#m → F#

vi-IV-I-V

A#m → F# → C# → G#

The Diatonic Family

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

Triads

C# D#m Fm F# G# A#m Cdim

7ths

C#maj7 D#m7 Fm7 F#maj7 G#7 A#m7 Cm7b5

Scale Compatibility

View All Scales

Diminished Ultralocrian Locrian 6 Dorian #4 Lydian Diminished Hungarian Major Lydian #9 Half-Whole Diminished Composite Blues Messiaen's Mode #7 Chromatic

* 11 scales found containing the notes A#, C#, E, G, Bb.

Acoustic & Digital Analysis

Digital footprint of the C#dim7/A# chord for MIDI programming and synthesizer sound design.

MIDI Numbers 70, 61, 64, 67, 70

Frequencies (Hz)

466.1637615180899, 277.1826309768721, 329.6275569128699, 391.99543598174927, 466.1637615180899