Transposition is the process of playing or rewriting a piece of music in other than the original key…
There are three reasons to develop this very learnable skill:
- To suit the key of the song to the comfortable range of the vocalist (a valuable skill for accompanists and band members).
- To suit the preferred keys for certain instruments in an ensemble setting. (a valuable skill for band members) Guitarists, for example, like to play in keys with open strings such as of E and A, while horn players prefer “flat” keys such as F, Bb, and Eb. By the way, I have never heard anybody ask the piano player what key they prefer! : (
- To be able to play a favorite lick, chord progression, or other pattern in a variety of keys (a valuable skill for Rock, Blues, and Jazz improvisers).