A Simple Guide to Transposing

Do you play a transposing instrument? Those new to the idea of transposing instruments—such as a Bb clarinet, soprano saxophone, or Bb trumpet—might find the concept a little tricky.

In reality, transposition isn’t all that hard to grasp. Put simply, a transposing instrument is one whose musical notes are written at a pitch different from actual concert pitch.

Instruments such as the piano, flute, violin, viola, and cello are not transposing instruments. If violinists see a C on the page, they play—and you hear—the note C.

Other instruments—including clarinets, trumpets, saxophones, and especially French horns—don’t sound a C when they play one on the page. For example, a “regular” clarinet is a Bb instrument. Notes for this clarinet are written one whole step higher than what the clarinet sounds, and a Bb  (one whole step, or two semi-tones, lower) is actually heard when a C is played.

There are several reasons why transposition is used.

One practical reason is that some instruments, such as the saxophone, come in different sizes to accommodate particular sounds and different ranges. Transposing allows, for instance, an alto sax (an Eb instrument) and tenor sax (a Bb instrument) player to see the same notes on the page and use the same fingerings. A written C will be the same fingering for both players, although different notes will sound from the alto and tenor.

Another common transposition practice is to notate music either an octave below or above what instruments actually play to avoid writing hard-to-read music with a lot of ledger lines above or below the staff. Instruments such as the bass or piccolo play in the key of C, but often transpose an octave.

Fortunately, most music will already be transposed for your instrument. However, sometimes musicians accompanying vocalists are asked to play music in a key other than what is written. This happens if a song, as written, is out of the range of the vocalist.

Of course, it takes practice to be able to transpose on sight, so musicians new to transposition might want to pencil in note names on a working copy of their sheet music. Modern technology can help. Music writing software such as Sibelius or Finale can be used to write out a new version of the music in another key.

Finally, when you sit down in a group to play, make sure you know what key your instrument is in and in what key the music is written. Don’t be afraid to ask the conductor or another player if you are not sure. Again, writing note names in pencil above the pitches will help you while you are learning a new piece.