Diminished

There are only three diminished chords, and each one has 4 inversions. you can take any note in a diminished chord and make that the root... which will give you another inversion

as a Migration Chord

Diminished chords are commonly used as "migration chords", whereby they will take us from one chord to another

Examples

• Bennie and the Jets at "...that's been known to change the weather"
• All Star - Smash Mouth at "...get your game on, go play"

as a Line Cliche

They are also used as line cliches, where we start with a more or less "normal" note, and move through a progression by dropping the base tone.

• to the ear, it seems all we are doing is just walking down the bass, but in reality we are creating a chord progression.

Examples

• Life on Mars - David Bowie at the intro, the progression goes F - Am/E - A°/E♭

Diatonic

Although diminished chords appear at the 7th scale degree in the major scale, they are not often used like this.

• the reason is because it's considered to be an incomplete version of the dominant chord.
  • ex. in the key of C major, the 7th scale is a B°, and the dominant is a G⁷, which contains all the notes of the B°.

Variations

Diminished chords can exist in 3 forms:

Diminished Triad

Often, diminished triads are not used, and instead a minor 7th is added. This is called a half diminished chord

• consists of root - minor 3rd - flat 5

Half Diminished

A diminished triad with a minor seventh added

Fully Diminished (a.k.a Diminished Seventh)

A diminished triad with a diminished seventh added (ie. stacking minor thirds)

• note: diminished seventh is enharmonically equivalent to a major sixth

Note the relationship between a fully diminished chord and the seventh chord 2 whole steps down from it (e.g. a fully diminished D# and a B7). The only difference between these 2 chords is that the diminished 7th is flattened, which now serves as the root for the seventh chord.