Diminished chords traditionally take the 7th position in a major key. Their spelling is generally 1-b3-b5, read as 1 flatted-3 flatted-5 for a half diminished chord, or 1-b3-b5-bb7 (double flatted 7 or a sixth note actually) for a full diminished chord or seventh diminished chord.
Diminished chords pull strongly toward the major chord which is a half-step higher. Interestingly, the intervals between the successive notes are all minor thirds, which makes their spelling symmetrical and quite easy to define and use in a number of situations. Because of this symmetry, each diminished chord can have 4 different letter names, since each note in the diminished chord spelling can be used to name the chord.
Let’s move it a step further. If you take each note in the musical alphabet and use the formula above to spell a diminished chord, you’ll get a total of 3 full diminished chords. Each chord uses 4 notes and the 3 chord spellings use all the notes of the musical alphabet. Here’s what we’re talking about:
Chord spellings (using the formula above):
1st group – D# – A – C – F#
2nd group – E – A# – C# – G
3rd group – F – B – D – G#
Are all the notes accounted for? Yep – A, A#, B, C, C#, D, D#, E, F, F#, G, and G#. Plus, each note in every chord can be the chord name; so the first chord can be named D#dim, Adim, Cdim, or F#dim. Plus, these notes in these chord spellings will always be the same. If you have an A# in a diminished chord, the other notes of that chord will always be E, C#, and G.
Dim chords are quite useful, but tend to be left out a lot in more current songwriting because the 5th position dominant chord can be used to replace them. So, for example, in the key of C, a B diminished chord can be replaced with a G7 chord. Why is that? Because most of the notes in a G7 chord (G-B-D-F) are the same as the Bdim chord (G#-B-D-F). Hmm… that’s interesting.
How To Make ‘Em
On the web, you can find a lot of fingerings for diminished chords, but here are a couple more thoughts to help you with the idea.
- To expand on the previous paragraph, in order to finger a diminished chord, you can use a ‘dominant’ chord shape, like an A7 or a D7 as your base for building the dim chord. Remember that a dominant chord is spelled 1-3-5-b7? If you’re unsure about dominant chords, just do a search on the site and a post should pop right up. Anyway, just take the 1-note in the dominant chord and ‘scooch’ it up (sharp it) a half step (or one fret). Remember that if you have more than one tonic or root note in the dominant chord it may sound a little too dissonant, because you have a ‘one’ note, plus a sharped ‘one’ note banging into each other.
- Another way to make diminished chords work is to use CAGED system chord shapes as your base chord spelling. Then convert them to a dominant chord, then sharp the one and voila! A diminished chord will magically appear. Here’s some help with that idea using the D chord shape as an example:
- Finally, if you just want some diminished chord fingerings, here are 3 string group versions that you may find helpful.
Each of the chord shape examples above are essentially the same chord; named differently based on the shape, but notice that all the notes of the diminished formula are in each chord shape. Also, if you re-position each chord shape up the fret board, in increments of 3 frets, you’ll still have the same chord. So, if you start at the 1st fret, using the same fingering, you can play the same chord at the 4th, the 7th, the 10th, and the 13th fret locations. Now suddenly, with 3 different shapes you could play, plus 4-5 locations, you have 12-15 more chords under your belt. As I use these, I tend to move them around to get a slightly different voicing.
Take a moment to comment below if you have any other thoughts or questions.
Until next time…
Bill Maxwell has over forty years of guitar playing experience and over twenty years of teaching students how to master the fretboard.