C#o11(#9) Diminished

The C#o11(#9) chord is built from the notes C# – E – G – Bb – D## – F#.

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Chord tones, one by one

C#Root

Root

The fundamental note the chord is built on — C#.

EThird

Minor third

Three semitones — makes the chord minor (darker, sadder).

GFifth

Diminished fifth (♭5)

Six semitones — a flat fifth. Creates instability, typical of m7♭5 and diminished chords.

BbSeventh

Diminished seventh (♭♭7)

Nine semitones — a doubly-flat seventh, found in fully diminished 7th chords.

D##Extension

Sharp ninth (♯9)

A ♯9 — the gritty 'Hendrix' tension over a dominant chord.

F#Extension

Eleventh (11)

An 11th — a suspended, airy color on top of the chord.

🎼 Related scales

🎹 Modal analysis

This chord implies the Whole-half diminished scale.

🎸 Genres

Bebop jazz · Hard bop · Gypsy jazz

o11(#9) in every key

More C# chords

More C# chords from Whole-half diminished