The Complete Idiot''s Guide to Music Theory

178 Par t 4:Accompanying

When you transpose a note or a melody or a chord, you take it from one key,

and instead play the equivalent note, melody, or chord in another key.

For example, let’s say you’re playing the note C in the key of C—the key’s tonic

note. When you transpose that note to the key of F, you now play an F—which

is the tonic note for the key of F.

Sounds easy enough, doesn’t it?

Let’s look at a more complex example: Let’s say you’re in the key of C and you

play a melody that moves from C to D to E—the first three notes of the C

Major scale. When you transpose that melody to the key of F, the new notes

(the first three notes of the F Major scale) are F, G, A.

Getting the hang of it yet?

Here’s another example: Let’s say you’re in the key of C, and you’re playing the

I-vi-IV-V chord progression—C-Am-F-G. When you transpose that chord pro-

gression into the key of F, the new chords are F-Dm-B
-C. It’s still I-vi-IV-V;

just in a different key.

You can transpose from any one key to any other key. That means you could

move the notes anywhere from a half step to a major seventh up or down from

where you started. (You also can move notes up or down by whole octaves—

what is called octave transposition—but you’re really not altering any notes;

you’re just changing octaves.)

Why You Need to Transpose

As you saw in the introduction to this chapter, there are many different reasons

you might need to transpose a song. Here are some of the most common:

◆The song, as written, is out of the range of a vocalist or instrumentalist. If

a singer can’t hit the high notes in the key of C, maybe the key of B or B
,

or even A might be friendlier.

◆You or another musician don’t know how to play the song in the given

key. This is especially a problem with beginning guitarists who don’t

always know the chords in some of the more extreme flat or sharp keys—

but they do know the chords for G and A and C and F. If you can trans-

pose the song to one of these keys, everyone can play their parts. (You

have the same problem with any instrument that has to deal with a lot of

sharps and flats in the key signature; it’s easier to play in C, G, D, F, and

B
than it is to play in the other, more complex, keys.)

◆You’re writing or arranging for one of the many instruments that don’t

play in what we call concert key.For example, trumpets always sound one

whole note lower than what is written—so you have to transpose all trum-

pet players’ music up a step so they’ll be in the same key as the other

musicians. (So if the concert key is C, you write the trumpet part in D;

when a trumpet plays a D, it actually sounds as concert C.) These instru-

ments are called transposing instruments, because you have to transpose

their parts for them.

Concert key or

concert pitchis the under-

lying key of a piece of

music—that is, the actual

pitches that sound when

played. The piano is

always in concert key.

Definition