Key Signatures

Topics covered on this page: Key and tonality – Major key signatures – Relative keys – Minor key signatures – Use of accidentals to for the various minor scales – The circle of fifths – Enharmonic keys – Parallel keys

Key Signatures identify all the sharps or flats used in a particular scale and are placed after the clef sign on the staff. By identifying the sharps or flats used in a key signature, it is not necessary to use accidentals on each note. The sharps or flats in the key signature apply to all following notes in any octave unless an accidental is used. This makes for music that is easier to read and less cluttered from superfluous notation. We will discuss how scales and keys relate to key signatures in the pages ahead.

A scale can be arranged in a stepwise series of notes to create a definite tonality, or key. The first and last note of a scale is the keynote -also known as tonic. This keynote is what all the other tones in the scale relate to. A musical piece that is strongly based around a G major scale, for example, is said to be in the key of G-major. Through repetition of a keynote in a piece or using the keynote in musical structure (phrase beginnings, rhythmic stresses, cadences, motives, etc.), the key is defined more clearly and emphatically.

In music notation, the key signature is placed on the staff on the right side of the clef sign.

G-major key signature:
3a

The sharps and flats on each staff line create the half and whole step patterns for a particular scale. Again, this eliminates the need for accidentals placed on individual notes throughout. A key signature takes care of that and it applies to all notes except those having accidentals.

Now that we have a solid understanding of what a key signature is, let’s discuss the written order of sharps and flats.

Sharps are written in this order: F C G D A E B. So if we apply one sharp to F we have the key of G-major (or relative minor of E-minor). If we apply one on F and a second on C we have D-major (or relative minor of B-minor), and so on. More on relative keys in the next pages.

1 sharp on the F note creates G-major:
3a

2 sharps on the F and C notes creates D-major:
4b

3 sharps on the F, C, and G notes creates A-major:
4c

4 sharps on the F, C, G, and D notes creates E-major:
4d

5 sharps on the F, C, G, D and A notes creates B-major:
4e

6 sharps on the F, C, G, D, A and E notes creates F#-major:
4f
7 sharps on the F, C, G, D, A, E and B notes creates F#-major:
4g

Note, music with 6 or 7 sharps is very uncommon in beginning through intermediate music studies.

There are two keys which have no sharps or flats: C major and A minor. Remember that the relative minor of C major is A minor. The relative major of A minor is C major.

Flats are written on the staff in this order: B E A D G C F. Below are all the flat key signatures.

1 flat on the B note creates F-major:
6a
2 flats on the B and E notes creates Bb-major:
6b
3 flats on the B, E, and A notes creates Eb-major:
6c
4 flats on the B, E, A, and D notes creates Ab-major:
6d
5 flats on the B, E, A, D and G notes creates Db-major:
6e
6 flats on the B, E, A, D, G and C notes creates Gb-major:
6f
7 flats on the B, E, A, D, G, C and F notes creates Cb-major:
6g

Note that as with sharps, music with 6 or 7 flats is very uncommon in beginning through intermediate music studies.

The same order of applying sharps and flats applies to other clefs. The clefs only identify the note range for the staff lines

Remember the order of sharps is: F C G D A E B.

The order of flats is: B E A D G C F.

Below are some key signature examples using C clefs…

The key of F-major on an alto clef:
7a
The key of D-major on a alto clef:
7b
The key of F-major on a tenor clef:
7c
The key of D-major on a tenor clef:
7d
The key of F-major on a mezzo-soprano clef:
7e
The key of D-major on a mezzo-soprano clef:
7f
The key of F-major on a soprano clef:
7g
The key of D-major on a soprano clef:
7h

Remember this clef is called a “C clef” because it identifies where middle c is located. Middle c is exactly between the treble and bass clef on a grand staff.

7i

Notice that the sharps/flats follow the same order regardless of the clef…

Alto clef sharps and flats:
8a
8b
Tenor clef sharps and flats:
8c
8d
Treble clef sharps and flats:
8e
8f
Bass clef sharps and flats:
8g
8h

As mentioned before, a key signature can either be major or minor. C major’s relative minor is A minor, which is a minor 3rd lower than C. Similarly, A minor’s relative major is a minor 3rd higher from the tonic, or keynote. So the relative major of A minor is C major. A few examples follow below…

F major or D minor:
9a
G major or E minor:
9b
D major or B minor:
9c
Eb major or C minor:
9d
Simply memorizing the sharps/flats related to each key is one way to learn, but another handy way is by counting the number of sharps or flats. When there are no sharps or flats we have C major:
10a

 

If the key signature consists of sharps, the major key can be determined by referring to the last sharp in the signature. This sharp indicates the 7th scale degree. The keynote, therefore, is a half step higher. (The interval of a half step separates the 7th and 8th degrees of the major scale.)

 

1 sharp on the F note which is the 7th scale degree of G major:
9b
Last sharp is on the C note which is the 7th scale degree of D major:
9c
Last sharp is on the G note which is the 7th scale degree of A major:
4c
Last sharp is on the D note which is the 7th scale degree of E major:
4d
The same rule applies to the remaining sharp keys.

If the key signature contains flats, the major key can be determined by referring to the last flat in the signature. This flat indicates the fourth scale degree. By counting scale degrees down from the last flat (4, 3, 2, 1), the name of the key can be determined.

Counting back 4 scale degrees from 1 flat on the B note gives F major:
6a
Counting back 4 scale degrees from the last flat on the E note gives Bb major:
6b
Counting back 4 scale degrees from the last flat on the A note gives Eb major:
6c
Counting back 4 scale degrees from the last flat on the D note gives Ab major:
6d
The same rule applies to the remaining flat keys.

Keys with two or more flats in their signatures have the word “flat” in their name. There are, for example, the keys of B-flat, E-flat, A-flat, and so forth. The key of F-major (one flat) is the only flat key which does not have the word flat in its name.

The circle of cifths is commonly mentioned in music theory and refers to the pattern of major keys related to the number of sharps. Each sharp creates a key a 5th higher clockwise from C.

Examine the circle of fifths chart below. From the outside to inside is the key signature, the major key, the number of sharps or flats, and the corresponding relative minor key.

14a

 

You may notice that there are sharps keys that sound the same as flat keys. C sharp major is the same key as D flat major. The same pitches but with different notation are known as enharmonic keys.

C sharp major:
4g

D flat major:
6e
Remember that a key signature can identify a major or minor key. These are called relative keys. A minor is the relative minor to C major. A the keynote or tonic of a relative minor is the 6th scale degree of a major scale. The keynote of a relative major key is located on the 3rd scale degree of a minor scale. The keynote between a major and minor key is a minor 3rd interval.

The sharps or flats in key signatures create the natural minor scale pattern.

Here is the key signature for F major, or the relative minor of D minor…

One flat gives the F major scale:
17a
One flat also gives the D natural minor scale:
17b
From starting with a natural minor scale, accidentals are used to adjust the natural minor into the harmonic minor and melodic minor. This example below shows how the accidentals are applied.

First we see the major scale in C:
18a
Here we have the relative minor which is the A natural minor scale:
18b
By applying an accidental to the G note (7th scale degree), we transform the A natural minor scale to the A harmonic minor scale:
18c

 

Finally, applying another accidental to the F note (6th scale degree), we transform the A natural harmonic minor scale to the A melodic minor scale. An interesting characteristic of the melodic minor scale is that the ascending version differs from the descending one. The descending melodic minor scale is simply the same as the natural minor scale.

Ascending:
18d
Descending:
18e

 

Major and minor scales which shares the same keynote are said to be parallel keys. The parallel key to A minor is A major. They have the same keynote but not the same key signature.

A major and scale:
19a
A minor and scale:
19b
G major and scale:
19c
G minor and scale:
19d

 

Next section is Triads