The
vibraphone (also called vibes or vibraharp) has metal bars arranged like
a piano keyboard with resonators underneath. The sound lasts a long time.
It has a damper pedal to control the ringing of the bars, and a motor-rotated
disk in each resonator which can be used to create a pulsating vibrato effect.
The vibraphone is usually played with rubber or yarn mallets. Information provided by: http://www.hypermusic.ca