What Are Related Keys and Why You Should Know Them!
1. Related Keys?
Related keys are an often neglected concept but appear surprisingly often within music. If a piece of music moves to a new key, the vast majority of the time it is moving to a related key. So knowing what those related keys are can really help you understand what is happening. It also opens up some interesting options if you are writing a piece of music or improvising!
There are 3 related keys for each major key and these are the keys that share the most amount of notes with the key that you are using. So when you move to a related key it’s like moving to an adjacent neighbourhood, everything feels somewhat familiar but it’s still novel and interesting. A listener will recognise most of the notes and chords but will also be able to hear that we’ve moved somewhere new.
For example, the key of C major has the notes C, D, E, F, G, A and B. On the piano, this is the white notes!
The related keys to C major are; G major, F major and A minor. For each major key the related keys are the keys based on the 4th note, the 5th note and the 6th note of your current scale.
G major has the notes G, A, B, C, D, E and F#. So this scale has only 1 note that is different from C major; the F#.
F major has the notes F, G, A, Bb, C, D and E. So this scale also only has 1 note different from C major; the Bb.
A minor has the notes A, B, C, D, E, F and G. This scale has exactly the same notes as C major. However, for minor scales we may often see the 7th note of the scale raised (G#) which would give us 1 note that is different from C major (you may also see the 6th note raised as well in some cases).
2. How to Use Them
For many musicians that are simply trying to understand the music that they are reading, knowing the related keys is a way of being able to interpret landscape shifts within the music. If a piece of music suddenly changes key, then this will feel like we have travelled somewhere new.
If our original key is C major, then knowing that the related keys are G major, F major and A minor is going to help us identify when these shifts are happening. For example, if we suddenly see many F#’s written into the music, then we have likely shifted to G major because this scale includes an F#. Whereas if we suddenly see Bb’s then we have likely moved to F major.
When a piece of music changes to a new key, it doesn’t simply just start using the notes from the new scale. The entire tonal center of the music shifts. This means that C will no longer feel like note 1 in the scale and a C major chord will no longer feel like chord 1 in the scale. Everything in the music from the melodies to the chord progressions will be centered around the new scale.
This means that in order to actually start using the new scale, certain things need to happen in order to facilitate that shift from one scale to another.
Firstly, you will often see a “pivot chord” which is a chord that is shared between the two scales. For example a D minor chord (D F A) is chord 2 in C major but it’s also chord 6 in F major. This is why related keys are much easier keys to move between, they share most of the same notes and therefore there are many chords that can be used as a pivot chord.
Following a pivot chord, we then need to confirm that we are in the new key. To do this, you will usually see chord 5 followed by chord 1 in the new scale.
So here is an example of some chords that would facilitate the pivot from C major to G major:
C major chord | Chord 1 in C (original key)
A minor chord | Chord 6 in C & Chord 2 in G
D major chord | Chord 5 in G
G major chord | Chord 1 in G (new key)
This type of technique can be used in your own music writing or improvisations to help broaden the types of sounds that are available to you. Writing a piece of music using one scale comes with its limitations, the sound can become rather predictable. By using shifts to the related keys, you can add new dimensions to your music and understand how many composers manage to keep simple musical ideas feeling fresh.
Matthew Cawood
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