The circle of 5ths (and 4ths)
Knowing your key signatures and understanding a few of the fundamental rules of key and harmony will allow for a greater awareness of the music that you play. This article will delve into a little bit of music theory, if you find anything a little confusing please do comment below or just email me directly at firstname.lastname@example.org and I will happily go through things with you.
Key Signatures, sharps, flats etc.
We will start with major keys, and will go from the key of C Major that has a key signature of no sharps or flats. The circle of 5ths will give a clear and simple way of working out which keys have sharps or flats in, and how many they have. It requires you to be able to count up to 5 and know your musical alphabet, (A, B, C, D, E, F, G and then back to A) and be able to start this on any note.
To make this work, it is going to be crucial to remember the following two points:
- That C Major has no sharps or flats in its key signature.
- When you count up in 5ths you need to include the note that you start on when you are counting. (More about this in a minute!)
We are going to work on the sharp key signatures first. We are going to find the key that has 1 sharp. We are going to use C Major to start with and count up 5:
1 2 3 4 5
C D E F G
Therefore, the key with one sharp is G Major. The note that is sharpened in this key signature is F. So G Major goes from G to G with an F sharp. To get to the key that has 2 sharps, we need to count up 5 notes from G:
1 2 3 4 5
G A B C D
Therefore, the key with two sharps is D Major. The notes that are sharpened in this key are F (as in G Major) and C. So D Major goes from D to D with an F sharp and a C sharp.
So why is this called the circle of 5ths? The key signatures are usually shown as a circle to make things easy to see and understand.
- C Major = 0 sharps
- G Major = 1 sharp (F)
- D Major = 2 sharps (F,C)
- A Major = 3 sharps (F,C,G)
- E Major = 4 sharps (F, C, G, D)
- B Major = 5 sharps (F, C, G, D, A)
- F# Major = 6 sharps (F, C, G, D, A, E)
- C# Major = 7 sharps (F, C, G, D, A, E, B)
To get the flat key signatures, instead of counting up 5 notes this time count up 4. Again include the note you start with. Starting again with C Major with no sharps or flats and then count up 4 notes:
1 2 3 4
C D E F
So F major has 1 flat and the note that is flattened is B. This means the F major scale goes from F to F with a Bb in it. The next flat key is worked out in the same way. Start with F and count up 4 notes:
1 2 3 4
F G A Bb
So B flat major has 2 flats in it and the notes that are flattened are B and E. This means B flat major goes from B flat to B flat with B flat and E flat in it.
- C Major = No flats
- F Major = 1 flat (Bb)
- Bb Major = 2 flats (Bb, Eb)
- Eb Major = 3 flats (Bb, Eb, Ab)
- Ab Major = 4 flats (Bb, Eb, Ab, Db)
- Db Major = 5 flats (Bb, Eb, AB, Db, Gb)
- Gb Major = 6 flats (Bb, Eb, Ab, Db, Gb, Cb)
- Cb Major = 7 flats (Bb, Eb, Ab, Db, Gb, Cb, Fb)
A simple way of remembering the order of the sharps and flats is by remembering this rhyme. Take the first letter of each word for the note that will be a sharp or flat:
Father Charles Goes Down And Ends Battle
For flat keys, use the same rhyme in reverse:
Battle Ends And Down Goes Charles’ Father
The major scales are placed around the outside of the circle; watch out for the post on relative minor scales on Sunday.