The alto clef determines the position of the C note on the staff (stave ):
From this reference, all others music notes will be placed before and after the C note:
What instruments use the alto clef?
The alto clef was used for the contralto voices (lower women voices), that's why this clef is called alto clef.
Nowadays the alto clef is used by:
- Viola da gamba
- Alto trombone
Alto clef and transposition
The alto clef is also used for transposition, useful for some players and conductors.
Example of using the alto clef to transpose:
Imagine that you are a clarinetist, so you play a transposing instrument and your instrument is in B flat, and imagine that you want to play a flute score (the flute is in C). So you are in B flat and you want to play in C: You will have to raise all the notes by one whole step (tone ), because between B flat and UT is one tone. By mentally substituting the treble clef of the flute score by an alto clef, you can transpose at sight the score:
You must also transpose the key by adding two sharps.
Key signatures in alto clef
Evolution of the C-clef symbol
In the book A history of music by Charles Villiers Stanford and Cecil Forsyth, a representation of the evolution of the C-clef clef symbol is exposed (source):
Learn to read alto clef
Here is a game to learn alto clef notes: