C7(#9) chord on electric guitar
C7(#9) is the dominant sharp ninth chord: C, E, G, Bb and D# (1–3–5–b7–#9). On electric guitar, the diagram shape is 0 1 1 0 1 0, with E in the bass.
On the electric guitar a chord needs only a few clear notes — the amp sustains them and fills the space, so you mute the strings you are not playing and let the tone carry the rest. In this C7(#9) voicing the bass is E and the shape sits at fret 1, ringing 3 open strings. Plugged into an amp, each chord sustains for as long as you hold it, and the tone — clean or driven — shapes the whole sound.
Notes and formula of C7(#9)
Notes in C7(#9): C – E – G – Bb – D#Formula: 1 – 3 – 5 – b7 – #9In 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.
Where to use it
Blues, rock and soul with an intense sound.
See also
Part of the Altered dominants family.