By the 19th century Polish and Russian performers had popularized the xylophone in western Europe. The celesta is a metallophone with a pianolike keyboard. A piano hammer action also strikes the glass bars of the glasschord, a 19th-century English crystallophone. The xylophone is a popular instrument in Africa and Southeast Asia. The wood bars are cut to different lengths so that each has a unique pitch.
Most xylophones sit on resonators, which can be very sophisticated or made from tin cans or gourds.
The instrument is played by striking the bars with sticks or mallets. Concussion idiophones are struck together, usually in pairs. Turkish-style brass cymbals and Spanish wooden castanets are the most familiar types, but ivory and bone clappers were common in ancient Egypt. Egyptian worshipers also used the sistrum, a rattle with metal rings fitted loosely on rods. Rattles are normally shaken rather than struck.