Muze Online: lesson 5 

Key signatures 

So far, we have discussed all the white notes on the piano: C, D, E, F, G, A and B.

Today we will look at the black notes, referred to as ‘sharps’ and ‘flats’. The signs can appear at the beginning of each stave (which describes the key signature of the whole piece) or in front of a single note (indicating that it only affects that one note for the length of one bar; in this case we refer to the sharps/flats as ‘accidentals’ because they are one-offs in a piece).

The picture to the right shows a natural, a flat, and a sharp. A natural negates what has otherwise been sharpened or flattened (e.g. if the key signature includes a sharp but this particular note should not be sharp, then a natural sign is needed to show this). A flat indicates for a note to be lowered by a semitone, whilst a sharp indicates for the note to be increased by a semitone.

  • A semitone is half of a whole tone. If you include all of the black notes when moving up or down the piano, each note will be a semitone above or below the last note. However, if you miss out a note (e.g. C to D, missing out C sharp/ D flat) then you have moved by a whole tone – a wider step in pitch than a semitone which is only half of the distance.

As you may have realised, the black notes on the keyboard are both flats and sharps: for example, C-sharp is the same as D-flat. Whilst the note is the same, these note names are called ‘enharmonic equivalents’, so D-flat is the enharmonic equivalent of C-sharp.

piano and notes.png

In order to work out our key signatures, we must be familiar with the order of the sharps and flats. Key signatures will only ever have either sharps or flats, not a mixture. The diagram above demonstrates the order of the sharps and flats as they are written on the stave.

The order of the sharps is as follows:

F, C, G, D, A, E, B (a helpful mnemonic I like to use is ‘Father Christmas Gave Dad An Electric Blanket)

  • A second mnemonic is 'Father Charles Goes Down And Ends Battle'

The order of the flats is as follows:

B, E, A, D, G, C, F (a helpful mnemonic fitting with the previous one can be used: ‘Blanket Explodes And Dad Gets Cold Feet)

  • The second mnemonic can be reversed for the order of the flats 'Battle Ends And Down Goes Charles' Father'

There are many ways to remember the orders, and to work out keys from key signatures, this is the way I was taught to work them out:

For sharp keys: count along the sharps in order, place your finger over the next sharp and the next sharp is the name of the key: e.g. D major includes F and C (cover G because it is the one before D). E major includes F, C, G and D (cover A).

For flat keys: count along the flats in order up to, including, and one after the key you want. E.g. A- flat major includes B, E, A and D flat. G-flat major includes B, E, A, D, G, and C flat.

F major is the one exception: the key signature for F major contains one B flat, it is best just to remember this exception.

The rules above work for major keys only, but every major key is related to a minor key, known as its ‘relative minor’. This is easy to work out because every minor key is three semitones below its relative major. For example, the relative minor of C major is A minor (and vice versa; the relative major of A minor is C major).

This week’s homework:

1) Practise writing out the sharps and flats on the staves in the correct order (copy the final diagram on the previous page). Also practise the natural sign from diagram 3.

2) Write out the key signatures for each major key and its relative minor (e.g. C major: key signature, A minor: key signature).

3) Find a piece of music, take a picture of the key signature and decide which major or minor key it could be (it will always be either a major key or the relative minor of that major. To decide if the piece is major or minor we will have to consider a few more details... more on this next time!)