Every singer has his or her own way of interpreting a song. Two singers rarely sing a song exactly the same way. Often a singer will learn a new song by getting the basic melody from another singer’s version and then changing it to suit their own style.
This may mean varying the length of notes, changing the rhythms, changing a few notes to different pitches, or even totally changing the melody. As long as the new melody fits with the lyrics, this is perfectly OK. In fact, some of the greatest recordings of songs have come about by the singer completely changing the melody and the accompanying musicians fitting their parts to the new version of the melody. Another situation where improvising comes in handy is in writing songs, particularly when you already have some lyrics and need to put a melody to them. There is always more than one way of doing this. Here are two different ways of phrasing the same lyrics.
In many melodies there is a natural accent on the first beat of the bar. This can be used to stress particular words in a song. In the first phrase of this example, the emphasis is on the word You.
In this version, there is a rest on beat one, and the first word sets up a different rhythm. You may prefer one approach or the other, but the two versions show that there is more than one way of approaching a lyric, a melody or a rhythm. In styles such as Rock, Blues, Jazz, Gospel and Hip-hop, improvisation is a large part of the singer’s art. Experiment with improvising on other songs you know.