Nowadays there are quite a lot of instruments, sound which arises from fluctuations of the elastic metal body. This triangles, gongs, bells, cymbals and other percussion instruments. They all are United by a common name - the glockenspiel.
One of glockenspiels, vibraphone, especially interesting for its design and expressive possibilities. It resembles a xylophone, but made of metal, not wooden plates. In addition, he has a special resonator tube with movable covers. These tubes facilitate periodic strengthening and weakening of the sound, i.e. the dynamic vibration, from which the instrument got its name.