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Chord & Fret

C7(#9) — dominant sharp ninth

Notes on C: C – E – G – Bb – D#Formula: 1 – 3 – 5 – b7 – #9

In the formula, the numbers count steps of the major scale starting from the note that names the chord; "b" lowers a half step, "#" raises one — and a slash names the bass note.

The 7(#9) layers the major third over the augmented ninth (the enharmonic of the minor third), creating an aggressive tension — the famous "Hendrix chord".

The same chord on all four instruments

C7(#9), 0 1 1 0 1 0C7(#9)123EBbEbGCE
Guitar
C7(#9), 0 1 1 0 1 0C7(#9)123EBbEbGCE
Electric guitar
C7(#9), 2 3 1 1C7(#9)2311EBbCEb
Cavaquinho
C7(#9), 3 3 0 3C7(#9)123BbEbEC
Ukulele

Where to use it: Blues, rock and soul with an intense sound.

This is just one shape of C7(#9). In Chord & Fret, you check it note by note, playing any shape as an arpeggio; compare positions with their difficulty marked; and change the tuning — the shape rewrites itself. Start free. Unlock everything with Pro. 100% offline.

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Part of the Altered dominants family.

Other chords in this family

C7(b9)C7(#11)C7(b13)

See all chord types and qualities →