Major Scales and Key Signatures
Senior 2 · Music
Major Scales and Key Signatures
Lesson 4 of 5
20 min
A choir is learning a new song, but the sopranos strain on the highest note. The leader does not throw the song away: she moves the whole song lower. Moving a piece of music up or down into a new key is called transposition. Musicians transpose to suit voices, to suit instruments, and sometimes simply to make a piece easier to read. This lesson also shows how one key can be written in two different ways.
In Lesson 1 you saw that C♯ and D♭ are the same piano key. Whole keys can be enharmonic too. F♯ major and G♭ major use exactly the same piano keys, but one is written with six sharps and the other with six flats.
| Sharp spelling | Flat spelling | Check |
|---|---|---|
| B major (5 sharps) | C♭ major (7 flats) | 5 + 7 = 12 |
| F♯ major (6 sharps) | G♭ major (6 flats) | 6 + 6 = 12 |
| C♯ major (7 sharps) | D♭ major (5 flats) | 7 + 5 = 12 |
In each pair the number of sharps plus the number of flats is 12. Musicians normally choose the spelling with fewer signs: D♭ major, with five flats, is easier to read than C♯ major, with seven sharps.
Worked example
Compare the two spellings of the same key. F♯ major is F♯ G♯ A♯ B C♯ D♯ E♯ F♯. G♭ major is G♭ A♭ B♭ C♭ D♭ E♭ F G♭. Note by note they are the same piano keys: F♯ = G♭, G♯ = A♭, A♯ = B♭, B = C♭, C♯ = D♭, D♯ = E♭ and E♯ = F. They sound identical.
Worked example
The melody below is the traditional French tune "Ah! vous dirai-je, maman", first published in 1761 and now sung to many sets of words around the world. To move it up a tone from C major into D major, write the key signature of D major (F♯ and C♯) and move every note up one letter step: C becomes D, G becomes A, E becomes F♯, and so on.
Compare the sol-fa lines: they are identical. A sol-fa name shows a note's place in the scale, so transposing changes the letter names but never the sol-fa. That is why a choir reading sol-fa can sing a song in any key: the leader simply gives a new doh.
Accidentals move too. Suppose a melody in C major contains F♯, a raised 4th degree (in sol-fa, fah raised becomes fe). Transposed up a tone into D major, F becomes G, so F♯ becomes G♯. The sign stays, because the note is still a semitone above the 4th degree of the new key.
Tip
Count letter steps, then trust the key signature. Move every note the same number of lines and spaces, write the new key signature, and it will add the right sharps and flats for you. Finally compare the sol-fa: if it matches the original, your transposition is correct.
Try each question first, then check the worked solution underneath.
Transpose the notes C E G up a tone.
Solution: D F♯ A. One letter step up gives D F A, and in D major every F is sharp.
Which major key is enharmonic with D♭ major?
Solution: C♯ major. D♭ major has 5 flats and C♯ major has 7 sharps: 5 + 7 = 12.
Transpose the first bar of the melody above (C C G G) into F major.
Solution: F F C C. From C up to F is three letter steps (C–D–E–F), so C moves to F and G moves to C.
A melody in G major is too high for a choir, so the leader moves it down a tone into F major. What happens to each F♯ in the melody?
Solution: It becomes E. F♯ is the leading note (t) of G major; one letter step down is E, the leading note of F major. F major has only B♭ in its key signature, so this E is a plain E.
Which is easier to read, B major or C♭ major? Why?
Solution: B major. It has five sharps, while C♭ major has seven flats, and the two keys sound the same.
Remember
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