Diminished

Half-diminished chords

Half-diminished: C-Eb-Gb-Bb. Formula: 1-b3-b5-b7. Also called 'minor 7 flat 5'.

In every key

The same shape, moved. The symbols below are spelled the way the app spells them, which is the spelling the chord's own scale asks for rather than whichever accidental is easier to type.

  • Cm7b5
  • Dbm7b5
  • Dm7b5
  • Ebm7b5
  • Em7b5
  • Fm7b5
  • F#m7b5
  • Gm7b5
  • Abm7b5
  • Am7b5
  • Bbm7b5
  • Bm7b5

Voicings

Written in C, because that is the key the encyclopedia authors them in; every one transposes unchanged.

Root Position

C · Eb · Gb · Bb

intermediate

Octaves shown are the app's default ascending voicing.

Drop-2

Gb · C · Eb · Bb

intermediate

Octaves shown are the app's default ascending voicing.

Rootless Type A (b3-b5-b7-9)

Eb · Gb · Bb · D

advanced

Rootless Type B (b7-9-b3-b5)

Bb · D · Eb · Gb

advanced

Drop-3 (b7-b3-b5-1)

Bb · Eb · Gb · C

advanced

Drop-3 half-diminished — b7 in the bass under the b3-b5-root

Rootless (b5-b7-9-b3)

Gb · Bb · D · Eb

advanced

LH 5-3-2-1; the D-Eb semitone at the top is the 9-over-b3 color — voice it gently.

Where it turns up

Essential iim7b5 in minor II-V-I. Creates tension in minor keys. Common in jazz standards.

Commonly swapped with

  • Ebm6
  • Am7b5/C

Progressions that use it

Every one of these is written out with the hands on a keyboard and on a stave.