Diminished Chords

Diminished Chords

During this course, we will tackle two types of diminished chords; The Minor 7 flat 5 (m7b5) and the Diminished 7th chord (dim7). Both of these chords are 7th versions of diminished chords but have a big difference which we will work out as we work through the chords. To start with we need to remember that our diminished triad is 1st, b3rd & b5th, as we will be building from there. We also will be using E as our example for each chord, so we need to get the E major scale written out as shown here:

Minor 7th Flat 5 Chords

Our first diminished chord is known as both "minor 7th flat 5" and "half-diminished". We feel as though the minor 7th flat 5 is a better and more suitable description, as well as the most common way you will see it written out. If you follow the basic logic in the name "m7b5", we can see that it is essentially a Minor 7th chord, with a flattened 5th. A minor seventh chord is constructed 1st, b3rd, 5th, b7th. So all we need to do is then flatten the fifth to get 1st, b3rd, b5th, b7th. Voila!

Minor 7th Flat 5 Shape

To help you put this into practice, in the fretboard diagrams is a common shape for the m7b5 in the key of E (as per the example above). Notice the notes on the neck as you go through it, trying to say the degrees of the scale (i.e. 1st, b3rd, b5th etc...).

Diminished 7th Chords

Our second diminished chord is known as both "diminished 7th" and "whole diminished". The difference between this diminished chord ad the previous is that you have got a flat, flat seventh! Yes, you read it correctly, you flatten the 7th note twice. When you do this you get the same b3rd interval (3 frets) between each note in the chord, which explains this concept of 'whole' diminished versus 'half'. The formula altogether is, therefore, 1st, b3rd, b5th & bb7th, as shown here:

Diminished 7th Shape

To help you put this into practice, in the fretboard diagrams is a common shape for the diminished 7th in the key of E (as per the example above). Notice the notes on the neck as you go through it, trying to say the degrees of the scale (i.e. 1st, b3rd, b5th etc...).

Harmonising The Scale

In this lesson, we recap some of the concepts we've learnt so far and remind ourselves of the formula that we need to remember to construct a key based on a major scale. Here is a recap of that formula:

Harmonising 7ths

Just as we did when we harmonised the key of C major to triads, we can now dot the same with 7th chords. The process is the same, you create the chord using just the notes in the C major scale. So, for example, when looking at D (The second degree of the scale) we know that a Dm fits in (using the notes D, F & G) and now we can use Dm7 as well because that has D, F, G & C in it, which are all notes from the C major scale. On the other hand, D7 wouldn't work here because it has D, F#, A & C. The F# is clearly not in the C major scale and therefore cannot be used. This is the process for each chord.

Once we have been through the process we are left with another formula to remember, which is as follows:

The Shapes On Guitar

To help you put this into practice, in the fretboard diagrams is a common way to play all 7 chords on the guitar. Try to put all of them together in this key (C major) to hear how they work together. Try to also refer to them as "first degree, 2nd, 3rd..." etc.