Vibrato is a vocal technique that adds a slight, regular variation in pitch to a sustained note. It is a characteristic of many singing styles, from opera to pop, and can add expressiveness and beauty to the voice.
There are many different ways to achieve vibrato, but the most common method is to use the diaphragm to control the airflow from the lungs. As the diaphragm contracts and relaxes, the air pressure in the vocal tract changes, which in turn causes the pitch of the note to fluctuate. Vibrato is also affected by the shape of the vocal cords and the position of the larynx.
