Minor seventh chord (m7) on electric guitar
Cm7 is the minor seventh chord: C, Eb, G and Bb (1–b3–5–b7). On electric guitar, the diagram shape is x 3 5 3 4 3, 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 Cm7 voicing the bass is C and the shape runs from fret 3 to 5. Plugged into an amp, each chord sustains for as long as you hold it, and the tone — clean or driven — shapes the whole sound.
Cm7 on electric guitar: shapes and notes →
Notes and formula of Cm7
Notes in Cm7: C – Eb – G – BbFormula: 1 – b3 – 5 – b7In 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
In pop and MPB it is the most common 'support' minor chord — the one that holds the harmony together without calling attention to itself. A classic example is Dm7Dm7Dm7Dm7 calling for G7G7G7G7 in the key of C, that is, setting the stage for the music to return to its main chord.
See also
Part of the Sevenths family.