While every song has major, minor and often dominant 7th chords it rare to come across diminished and augmented chords. These dramatic sounding chords are used to create tension in music and can add complexity to the chord harmony of a song. In this guitar lesson you will learn how to play these chords and use them in songs.
Diminished 7 Chords
These chords were used in old silent movies to create tension with their “scary” sound. This sound was especially effective in building suspense when someone was tied to the railway tracks and the train was approaching!
The diminished 7 chord consists of three minor 3rds stacked on top of each other. The name diminished comes from the fact that the minor 3rd is a diminished major 3rd.
The diminished 7 chord is a strange chord as there really are only three different ones, C, C# and D. The notes of C diminished 7 are the same in Eb, F# and A diminished 7 with these chords simply being inversions of C diminished 7. However while the notes are the same in these chords the notes are labelled or spelt differently. The chord symbol for a diminished 7 chord is a “O”.
Therefore C# diminished 7 uses the same notes as E, G and Bb diminished 7 and D diminished 7 has the same notes as F Ab and B diminished 7. How these chords are labelled or spelt depends on the key of the song.
There are 2 main ways of playing the diminished 7 chord on the guitar. One is by playing the 5 string dominant 7 shape and moving the bass note up one fret. For example play B7 then change the bass note to C to play C diminished 7.
 | C Diminished 7 | Download |
The other is by barring the top 4 strings and adding fingers 2 and 3 to create a zigzag pattern.
In a chord progression the diminished 7 chord can be used to create tension that wants to resolve to another chord. The chord is commonly used in a jazz blues progression as a sharp IV diminished 7 chord played between the IV7 chord and the I7 chord. In the key of F the chords are Bb7, B diminished 7 and F7. The B diminished 7 chord is the same as Bb7 with B natural in the bass with the following chord being F7. This B natural note wants to move to C which can is the bass note of the following F7/C chord.
| Jazz Blues Diminished Progression | Download |
In Road Trippin’ by the Red Hot Chili Peppers the D# diminished 7 chord shape slides up and down the guitar neck to play all 4 inversions of the chord before resolving to the Em chord at the start of the last verse. The D# from D# diminished 7 leads to the E note in Em while the F# note from D# diminished 7 pulls to G note in the Em.
| Road Trippin | Download |
Half Diminished 7 Chords
The half diminished chord is shorter name for the minor 7 flat 5 chord. The difference between this chord and the (full) diminished 7 chord is that the top or 7th scale degree note is a semitone (1 fret) higher. For example the notes of C half diminished 7 are C Eb Gb and Bb verses the notes of C diminished 7 being C Eb Gb and A (aka Bbb).
The chord symbol for a half diminished 7 chord is a “O” with a slash “/” through it.
| C Half Diminished 7 | Download |
The half diminished 7 chord is used as the 2 (ii) chord in a minor progression and appears in many jazz and minor blues tunes. A classic example is a ii V i progression. Jazz tunes that include this are:
– Sugar – Stanley Turrentine
– Stray Cat Strut – The Stray Cats
– Blue Bossa
– My Funny Valentine
| ii V i | Download |
Augmented Chords
Augmented chords are a created by stacking the notes in two major 3rds. So the notes of C augmented are C E G#.
The chord symbol for an augmented chord is a “+”.
| C Augmented | Download |
The augmented chord is sometimes used as a substitute for the dominant 7 chord. In a blues it is used as the V chord. A well known song that uses the augmented chord like this is Stormy Monday by T Bone Walker.
| Stormy Monday| Download |
One final more famous example that uses an augmented chord is the introduction of Mama Mia by 70s Swedish pop superstars ABBA. The beginning hook uses D major and D augmented chords played back and forth. The D augmented chord creates tension that is resolved whenever the song moves back to D major.
| Mama Mia| Download |
Now you’ve deciphered these chords on the guitar see how you can apply them to songs that you play or in the music that you write.
