Timpani, also known as the kettledrum, is a musical instrument in the class of percussion instruments, belonging to the subcategory of membranophones. It is a semi-spherical drum that consists of a head, also known as a membrane that is stretched over a bowl made from metal, usually from copper or, on cheaper units, from aluminium or from fiberglass. Modern timpani drums come with a pedal that makes tuning easier and they are played with special sticks used for hitting the head of the timpani.
Timpani comes in various sizes, from as small as 30 cm in diameter to pieces that measure around 85 cm across. The materials used for making timpani heads include goatskin or calfskin or from plastic, most commonly from PET membrane, each material being used for delivering different sound (the heads made from natural leather create a sound considered to be warmer). The tools used for playing the instrument are also varied – timpani drums are either played with sticks or with mallets. The sticks are composed of a shaft traditionally made from hardwood or bamboo or, in modern sticks, from aluminium or carbon fiber, while the head is made from leather, wood, flannel or from felt wrapped around a piece of wood.