VIBRAPHONE

also called Vibraharp, or Vibes, percussion instrument that has tuned metal bars and is similar in shape to a xylophone. Felt or wool beaters are used to strike the bars, giving a soft, mellow tone quality. Suspended vertically below each aluminum bar is a tubular, tuned resonator that sustains the tone when the bar is struck. The special feature of the vibraphone, the one that gives the instrument its name, is a set of small, electrically operated fans above the resonators (and below the bars) that cause a vibrato effect by rapidly closing and opening the resonators. A pedal-controlled damper, consisting of a long strip of felt below each row of bars, can silence the bars, permitting the playing of short notes and unblurred series of chords. Cutting off the fans, changing their speed, or using hard mallets are other ways to alter the normal tone quality of the vibraphone. The vibraphone was invented in about 1920 and was soon common in dance bands and became a prominent jazz instrument. Its foremost jazz practitioners were Lionel Hampton, Milt Jackson, and Red Norvo. The vibraphone was first used in the orchestra in Alban Berg's opera Lulu (1937). The instrument's compass varies; three octaves upward from the F below middle C is common.