How To Use Diminished 7 Chords On Guitar - 4 Examples

What's a Diminished 7 Chord?

A diminished 7 chord is a four-note chord that consists of :

 R/1 (root / tonic) - ♭3 (minor third) - ♭5 (diminished fifth) - and♭♭7 (diminished 7).

For example,  a  C diminished 7 chord would consist of the notes C (root), E♭ (minor third), G♭ (diminished fifth), and B♭♭ (diminished seventh).

On the guitar, you can play a C diminished 7 chord like this:

Symmetry Of Diminished 7 Chords

One very important thing about diminished 7 chords is that they are symmetrical in nature, meaning that their structure repeats at regular intervals.

This symmetry arises from the equal spacing of minor thirds within the chord.

A diminished 7 chord is constructed by stacking three minor thirds on top of each other.

Let's take an example to illustrate this. Consider the diminished 7 chord built on C:

1. Start with C.
2. Add a minor third above C, which gives you E♭.
3. Add another minor third above E♭, which gives you G♭.
4. Finally, add one more minor third above G♭, which gives you B♭♭.

Because of the symmetry, you obtain three other diminished chord starting on each note of the C diminished 7 chord that are E♭dim7, G♭dim7 and B♭♭dim7 (Adim7 if you prefer).

In other words, each note of a diminished 7 chord is a root note.

Four Tips To Use A Diminished 7 Chord

To use a diminished 7 chord in a musical context, you can apply it in various ways, here are 4 examples:

1 - Jazz Blues Progression - Between IV7 and I7

Diminished 7 chords are often used in jazz blues progressions between the IV7 and I7 chord in the second and sixth bar as shown in the chord changes below.

F7  |  B♭7  Bdim  |  F7  |  Cm7  F7  |

B♭7  |  Bdim |  F7  |  D7♭9  |

Gm7  |  C7  |  F7  |  %  ||

2 - Substitute For Dominant 7 Chord:

A diminished 7 chord can serve as a substitute for an altered dominant 7 chord (typically featuring a flat 9) provided that the diminished 7's root is positioned a half-step above the root of the dominant 7 flat 9 chord.

Example with this ii V I progression:

Dm7  |  G7alt  |  Cmaj7 would give Dm7  |  A♭dim7  |  Cmaj7

3 - Walking Between Dominant Chords

The following technique is great to move between dominant chords thus creating a smooth bass line with chromatic passing tones.

The chords used are named shell voicings also know as 3-note chords.

In the example below you can hear two diminished 7 chords :

• Bar 1 : D♭ diminished 7 to make the link between Cm7 and B♭/D.
• Bar 2 : G♭dim7 between Fm7 and E♭/G.

You'll find the complete etude here in this PDF method called 11 Jazz Blues Studies For Guitar.

4 - Passing Diminished Chords

Diminished 7 chords are often used to create tension that resolves to a stable chord (tension and resolution).

For example, it can be used as a passing chord leading to a major or minor chord.

The example below show how diminished 7 chords can be used as passing chords between each chord of the diatonic scale in C major.

Cmaj7  D♭dim7  Dm7  E♭dim7  Em7  Fmaj7  G♭dim7  G7  A♭dim7  Am7  B♭dim7  Bm7♭5