Vibraphone

Vibraphone, electric percussion instrument resembling a xylophone but having metal rather than wooden bars. The vibraphone has 37 bars (keys), each attached to a frame above a tuned resonator that can be opened or closed to produce a vibrating note. The player uses hard or soft cloth-headed beaters to strike the keys and can control the length and loudness of the notes with a sustaining pedal. The vibraphone was invented (1921) by Hermann Winterhoff and was first used orchestrally in the opera Lulu (1937).