Question

Why do we need to write music in different key signature?​

Answer 1

Music for solo voice and piano is often made available in different keys to suit the voice range of different singers. You would notice if the same singer sang a song in different keys because it would lie differently within the voice range.

Answer 2

In music notation, the key signature tells the reader which notes to play sharp or flat throughout the music. If you are playing a song in a certain key, the same notes will be sharp or flat throughout the entire song. ... That means every F and C you encounter in the music are to be played as Fand C.

Step-by-step explanation: