Orchestra Final Practice Test

Vibrato on string instruments adds warmth and color to a sustained note by making the pitch wiggle gently around the written pitch. This oscillation is produced by rocking the left-hand finger on the string while keeping contact, which changes the string tension just enough to raise and lower the pitch in a controlled way. The speed of the wobble is how quickly those pitch changes occur and shapes the character of the vibrato. The width is how far the pitch moves from the central pitch, which determines how wide the tonal color feels. Finger pressure influences how easily the finger can drive that motion and how pronounced the pitch excursion becomes. The central pitch stays anchored, so the note remains on pitch even as its color shifts. Vibrato serves expressive purposes, helping the tone blend with ensemble sound and conveying musical emotion; it is not used to set tempo or to dampen the sound.