More today about the timpani, or kettledrums. The “kettle” of a kettledrum is called the “bowl,” and is made of copper or brass. The “head” of the drum, the surface that the player strikes, is a piece of Mylar plastic stretched over the rim of the bowl. Timpani heads were originally made of calfskin, but calfskin is very sensitive to changes in temperature and humidity, and it’s expensive, so although some players still prefer the sound of calfskin heads, these days most players stick with