Diminished Chords, Arpeggio and
Scale Applications (Part 1)
Podcast #16 - Additional notes
© Copyright Darren Dutson Bromley 2013
Its often been my experience as an educator that the diminished chord, arpeggio and in
particular the diminished scale is often a bit of a grey area so I’d like to spend the next few
weeks looking at their construction, application and use. We’ll begin with the diminished
chord.
The diminished chord is very useful chord with a wide range of applications. It can be
found in jazz, blues, metal and rock, country and classical.
It is constructed from the root, b3rd, b5th and bb7th notes of a major scale.
Here is an example showing how the C diminished chord is constructed from the C major
scale.
C
C
D
E
Eb
F
G
Gb
A
B
Bbb
A peculiar trait of the diminished chord is every note is a minor 3rd or three frets apart, as
a result each note can be thought of as a root note and the chord repeats every three
frets.
C diminished contains the same notes as Eb diminished which contains the same notes as
Gb diminished which is the same as Bbb diminished. You would very rarely, if ever hear
the term Bbb diminished, it would normally be named after its enharmonic equivalent, A
diminished.
root
2nd
3rd
4th
5th
6th
7th
Eb
F
G
Ab
Bb
C
D
Eb
Gb
Bbb
(A)
Dbb
(C)
Eb major and Eb diminished.
root
2nd
3rd
4th
5th
6th
7th
Gb
Ab
Bb
Cb
Db
Eb
F
Gb
Bbb
(A)
Dbb
(C)
Fbb
(Eb)
Gb major and Gb diminished.
root
2nd
3rd
4th
5th
6th
7th
A
B
C#
D
E
F#
G#
A
C
Eb
Gb
A major and A diminished (the enharmonic equivalent of Bbb)
The diagram above shows how a diminished chord shape repeats its self every three frets.
Each of the notes can be classed as a root note. C diminished, Eb diminished, Gb
diminished and A diminished contain the same notes. The name used for a particular
diminished chord is determined not by the notes in the chord but by the function of the
chord and its applied use.
For example a progression which read:
Fma7 Gbdim Gm7 would be correct, the Gb clearly showing the chromatic root
movement of F, Gb and G.
The progression could also have been written:
Fma7 Cdim Gm7. Whist C diminished contains the same notes as
Gb diminished the application of the diminished chord as passing chord between F and G
is unclear. This would be confusing to read and may well be interpreted wrongly.
There are many examples of this in many published real books, diminished chords nearly
always have a function and it is this particular function which should prescribe its name.
Using the diminished chord as a substitute chord.
A very common use of the diminished chord is as a substitute for a dominant 7th chord.
Playing a diminished chord built on the 3rd of a dominant 7th implies a 7b9 chord.
G7 contains the notes G B D and F.
B diminished contains the notes B D F and Ab.
Three of the notes are common to both chords while the Ab found in B diminished implies
a b9th chord (Ab is the flattened 9th in a G scale)
A progression such as Dm7 G7 Cma7 could be played as Dm7 Bdim Cma7.
Dominant Approach Chords.
A useful harmonic device is to approach a chord with a dominant 7th whose root is a 5th
above. This is a particularly strong progression and can reinforce a chord sequence
making it very clear as to where it is moving to harmonically.
For example here is a common chord sequence:
It is possible to approach the Am7 with a dominant chord who's root lies a perfect 5th
above. The note a perfect 5th above A is E so the chord E7 can be used as an approach
chord.
Whilst the E7 chord is not part of the key of G major it doesn’t sound out of place and
reinforces rather well the change onto Am7.
We could substitute a diminished chord built on the 3rd of E7 as a replacement for E7. The
3rd of and E7 chord is the note G#. G#dim could be used as a substitute for E7:
This gives an interesting chromatic root movement between the Gma7 and Am7.
Let's try the same approach with another progression.
To this it is possible to insert a dominant approach chord for Am7, a dominant 7th whose
root lies a perfect 5th above, this would be E7. The same could be done with Bm7. The
note a perfect 5th above B is F#, an F#7 chord could be used as an approach chord to
Bm7. Finally an approach chord to lead onto Cma7 would be G7. The progression could
now look like this:
It would then be possible to play a diminished chord built on the 3rd of all the dominant 7th
chords, this could create some interesting root movements and is a useful way of creating
a real cohesive quality to a chord progression.
Try using this technique in other sequences and songs. Next week we’ll look at more
diminished applications.