About CmMaj7b5 — drop 2 voicings
CmMaj7b5 is C, Eb, Gb and B — Cm7b5 with the seventh raised a semitone.
It sounds brittle and impossible to mistake. Scarce enough that most players meet it as a passing sonority rather than as a chord they chose.
Rare tonic — a half-diminished chord with its seventh raised instead.
CmMaj7b5 notes and formula
| C | Eb | Gb | B |
|---|---|---|---|
| 1 | ♭3 | ♭5 | 7 |
Also written CmM7b5 or Cm(maj7)b5. The same chord either way; which spelling you meet depends on who wrote the chart.
How to play CmMaj7b5
Take the four notes stacked as close together as they go, then drop the second voice from the top an octave. The gap it opens is what makes the chord sound like a chord rather than a cluster.
It lands on four adjacent strings, which is why it is the workhorse voicing on guitar.
CmMaj7b5 has 12 of them, on the middle four strings, the top four strings and the bottom four strings, from open position up to the 11th — every inversion the chord has: C in the bass, Eb in the bass, Gb in the bass and B in the bass. The one to learn first is the C shape at the 3rd fret, which is the easiest grip here.
4 of them sit on the middle four strings, so you can run the inversions up one set without changing strings — which is the whole reason to learn them as a family rather than as separate grips.
Play CmMaj7b5 as a shell — root, third and seventh — and the spare string takes the 11 (F) or the b13 (Ab).
All 5 common shapes as fret numbers, lowest string first. Hover or tap one to see it drawn.
- x3x442, 2nd fret, C, root position, top note Gb, all fretted
- x3444x, 3rd fret, C, root position, top note Eb, barred
- 89x877, 7th fret, C, root position, top note B, all fretted
- 8998x8, 8th fret, C, root position, top note C, barred
- x-x-10-11-12-11, 10th fret, C, root position, top note Eb, all fretted
What to play over CmMaj7b5
Every note of CmMaj7b5 is in C diminished.
Chords near CmMaj7b5
Change one note of CmMaj7b5 and you have Cdim (drop the major seventh), Cdim7 (the major seventh becomes the diminished seventh), Cmaj7b5 (the minor third becomes the major third), Cm7b5 (the major seventh becomes the flat seventh) or CmMaj7 (the flat fifth becomes the fifth).
CmMaj7b5 is a diminished chord — root, minor third, flat fifth. Diminished and half-diminished chords on every root.
The common shapes and the derived voicings come from different places, and both are explained in how this site is built.