Drums are percussion instruments that have a thick membrane or skin, stretched tightly over its hollow body. They have been used for a long time, and are played with sticks, mallets, or hands. When the instrument is struck, the skin gets pushed down. It then starts vibrating, going up and down multiple times in a second. When this vibration pushes the air, sound waves are created.
There are many factors that affect sound production in drums. If the head portion of the instrument is large, it produces a low-pitched sound. With a large body, drums absorb higher frequency sounds, while amplifying lower frequencies. As a result, a warmer tone will be produced. If the body is small, the sound generated will be sharp and bright.
Another important consideration is the volume of air inside a drum. The higher the volume, the lower will the notes be. A further factor is the way with which the instrument is struck.