Transposition is a topic I have received a number of questions about, like this one,
“I know already all the scale of my alto sax,even all the major scale. The only thing that i don’t know. How to use it and to transpose to alto notes?”
Why do we need to transpose?
There are advantages and disadvantages to the standard key system across the saxophone family.
It allows you to easily transition between saxophones when you read music.
But it also means you should know about a process called ‘transposition’.
We need to transpose music sometimes when we see or hear people talk about music that is in ‘concert’ or intended for another instrument. Also between the saxophones.
Keys of the different saxophones
Tenor and soprano saxophones are in the key of Bb
Alto and bari saxophones are in the key of Eb.
Intervals and mathematics
The music you want to transpose is very likely in concert pitch (the key of C).
That means if you play a C on your alto saxophone, it’s the same as an Eb on piano.
What’s the difference between C and Eb? What’s the distance or interval between them?
C up to Eb is a minor third (three half steps).
C down to Eb is a major sixth.
How to transpose
Taking music from concert key to Bb and Eb or from Bb to Eb/Eb to Bb can be a little bit tricky. But there are simple rules that you can learn which involve adding/subtracting numbers for intervals.
The tenor saxophone and soprano saxophone are both in Bb. So if you have music in concert key and you’re playing tenor/soprano, you just have to go up a whole step since Bb is a whole step below C.
The alto saxophone and baritone saxophones are in Eb. So you can either go down a minor third or up a major sixth. Eb is a minor third above C.
The keys of Bb and Eb are a perfect fourth apart.
A few examples
Concert C = D for tenor/soprano = A for alto/bari.
Concert Bb = C for tenor/soprano = G for alto/bari.
Concert Eb = F for tenor/soprano = C for alto/bari.
Db on piano -> Bb on alto saxophone
A on piano -> F# on alto saxophone
For alto sax, I like to think about it as a minor third since it’s not as wide of an interval and the minor third is pretty familiar.
For tenor saxophone, if you read music written in C (piano music for example) you go up a whole step to transpose it. If you see a Bb, you play C, if you see a G you play A, etc.
Not too hard to get comfortable just playing music by thinking ‘up a whole step’.