Transposition


It's important when composing to understand the range of various instruments. And when arranging, it's necessary to know how to transpose a melody, passage, or an entire song to fit within the range of a vocalist or instrument.

Starting with vocal ranges. In choral writing, voices are divided into 4 broad categories: bass, tenor, alto, and soprano (usually written SATB on choral publications). Sometimes you see 1st and 2nd soprano, mezzo-soprano, baritonem etc. but we'll stick tO SATB for now. Below are suggestions for ranges:

When writing for instruments, it's important to understand that some instruments are "transposed" and some are not.

A transposed instrument produces a pitch different than the one written. That is to say the music which is read by the performer is actually different than the note produced. It is written to be easier to read by the performer.

So the performer might think he's playing a C when actually he's playing an Eb. (Now most performers understand this). It is then necessary to write the music for a transposed instrument so that you hear the notes you want. This will require you to transpose the music, so that when played, the transposed instrument will transpose it back to the correct note.

Some instruments come in a number of keys, so for example below is a listing of how playing a C on various trumpets would actually sound:

{insert graphic]

Below is a list of some transposed instruments. Note: the guitar is a transposed instrument, but it is transposed by an octave, so a C still sounds a C, just 1 octave lower than written.

2 octaves higher
Orchestra bells

1 ocatve higher
Piccolo, xylophone, celesta

M2 lower
Bb clarinet, B trumpet

m3 lower
A clarinet

P5 lower
english horn, Horn in F

M6 lower
alto sax

ocatve lower
contrabassoon, bass, guitar

Octave + M2 lower
Bass clarinet, tenor sax, barritone

Octave + M6 lower
barritone sax

There are a couple of ways to transpose. You can:
1.) transpose by interval,
2.) transpose by clef, or
3.) tranpose by means of a device (which in turn does #1 for you)
4.) on the guitar you can use a moveable chord/scale, etc. andtranspose on the fly.

Transposing by intervals
To transpose by intervals we start with what we are transposing, and then write on another staff the same inetrvals starting at another place. Let's consider the following phrase and 2 different ways to do this. First in C.

Now, I'd like a trumpet in Eb to play that, as I write it here, but if the trumpet (in Eb) player reads from that they will play something different. So I need to write everything a m3 lower, like so:

Now, I could haven taken every note and lowered it a m3, or I could have just moved the C down a m3, and then replicated all the changes from note-to-note such as start on A, then move up a whole step, then up a whole step, then up a m3, then back to A.

While the latter may seem cumbersome, it can lead to other ideas such as inversion, etc. that the previous would not lead to.

The second way was clef transposition.
So we'll lower the melody an octave and consider that all the following say the exact same thing.

Those C-clefs get used by string instruments and middle C is found in th emiddle of the C-clef sign.

Using the proper clef reduces the number of ledger lines overall.

Those transposing may find use in a transposition chart (see html://simianmoon.com/snglstringtheory/guitar/8theory3.html)(?)

If you play the guitar, then transposing can be as simple as placing a capo on the guitar at the proper fret (see html://simianmoon.com/snglstring2/fretboard/capo.html)

And if you don't have a capo, using moveable chords/scales can simplify something like shifting keys by a 1/2-step or whole step (that's just one of the things which makes the guitar a superior instrument).

Some companies have also created effects devices such as pitch-shifters which with the click of a button will electronically switch the pitch for you.

I will try to put up a sheet with exercises to transpose.

Next lesson is on cadences.

Peace,
Christopher Roberts
snglstringtheory@aol.com


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Last updated June 12, 2003
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