Tuesday, June 9, 2015

How to Transpose a Soprano Saxophone to Alto

The alto sax is pitched in Eb.

Transposition is a process that involves changing the pitch of an instrument by a set interval. Because the soprano and alto sax play in different keys, to enable both instruments to play the same pitch, a transposition is necessary. Transposing a soprano sax to an alto sax requires knowing the sounding key of each instrument, then transposing the soprano sax in relationship to the alto sax.

Determine what interval will transpose soprano sax to alto sax. The soprano sax sounds a major second lower than written and is in Bb. The alto sax sounds a sixth lower and is in Eb. This means that the alto sax transposition is down a perfect fifth from soprano sax.

Remove one flat from the key signature. Since the transposition is a perfect fifth, you must also change the key signature to reflect this change. If there are sharps in the key signature, remove one sharp, as sharps cancel out flats. Transpose all of the soprano sax's notes down a perfect fifth. This in correlation with the key signature change will allow you to play soprano sax music on an alto sax.


  • A perfect fifth is equivalent to seven half steps.
  • To transpose down a fifth, the transposed note must be both seven half steps and five notes names. For instance, a perfect fifth below C# is F# and not Gb.
  • The chromatic scale used to determine half steps is C : C#/Db : D : D#/Eb : E : F : F#/Gb : G : G#/Ab : A : A#/Bb : B. The notes separated by a slash are called enharmonics; notes that sound the same but are written differently.