Vibrato is a series of very quick changes up and down to the pitch of a note. It is like a deliberate, controlled wobble. The word “vibrato” is related to the word “vibrate”.
Vibrato is used to make a melody sound more beautiful by making it more expressive. Singers use vibrato, especially when singing dramatic solo music such as opera. In Italy a singer’s vibrato is sometimes called “tremolo”.
Violinists and other players of string instruments produce vibrato by moving the finger backwards and forwards on the fingerboard. Vibrato has to be learned carefully, as the hand needs to be very relaxed. Many beginners who start to use vibrato will try to vibrate too fast and this makes an unpleasant sound. Vibrato can be produced on wind instruments by small changes of breath control.
Musicians sometimes disagree about how much vibrato was used in earlier times. People who play music from the Renaissance or Baroque on period instruments sometimes play without any vibrato. Other people think that players of those days did use some vibrato.