Cm9 chord on electric guitar
Cm9 is the minor ninth chord: C, Eb, G, Bb and D (1–b3–5–b7–9). On electric guitar, the diagram shape is x 3 0 0 4 6, with C 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 Cm9 voicing the bass is C and the shape runs from fret 3 to 6, ringing 2 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 Cm9
Notes in Cm9: C – Eb – G – Bb – DFormula: 1 – b3 – 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
The heart of neo-soul and R&B vamps — that is, those short two-chord passages that loop over and over while the melody floats on top. It also works as the arrival chord in a minor key, smoother and more modern than a plain m7.
See also
Part of the Extended family.