The Timpani is arguably the best known of the modern percussion instruments. They come in various sizes, construction, and have different types of tuning. In a very general sense, the modern timpani is tuned by means of a series of tuning rods, going through a steel ring held down over the skin. This type of modern tympani has a foot pedal which are connected to the tuning rods with a series of steel rods. The performer presses the foot pedal down, and the rods pull down on the tuning rods, tightening the ring and skin, thereby raising the pitch. A skilled timpanist can accurately determine how much pressure he needs to place on the pedal to achieve a defined pitch, and vice versa, and can push the rear of the pedal to release the tension to lower the pitch. Another tuning mechanism on a timpani is a single tuning rod that is connected to all the others by a chain and gears, so when the timpanist rotates the tuning rod, it proportionally changes all the others as the chain moves. The tuning rod is usually equipped with a handle or a place to attach a crank, making the timpanist’s job easier.
The modern timpani is normally constructed of copper drums, or kettles, over which a plastic skin is stretched. The performer strikes the skin, with single or multiple strokes, and adds further variation of tone with the use of mallets of varied construction. A hard mallet, with a wooden ball or head brings a sharp tone, where a soft mallet head, often made of cotton or wool give a much softer tone. The user may ascertain from this brief description that the hard mallet produces a much harder attack than the soft mallet, and the composer can exploit this in a variety of instructions to the timpanist, defining which head, and technique is to be used, with a series of notational symbols.