How Drums Work

Drum Structure

A drum usually consists of a skin, a shell or body and some mechanism that holds the two together. The skin of the drum is a flexible membrane, stretched tightly across the rim of the shell. Traditionally, skins were made out of animal skins, but set drums and some hand drums now use synthetic skins. The skin can be held onto the rim in a variety of ways. Some traditional drums, such as the Irish bodhran, use tacks or glue to hold the skin in place. Others use ropes or adjustable metal brackets to attach the skin to the body.

Tuning Drums

Before playing a drum, a player will often tune it. Changes in humidity and temperature, as well as wear and tear on the skin, can change the tuning, making the drum sound too low or too high. If the skin is attached to the drum with rope, the drummer can pull the rope tighter to raise the pitch or loosen it to lower the pitch. If the drum has modern metal brackets, the drummer can tighten or loosen nuts attached to the mounting hardware with a wrench to change the pitch. Even fixed-skin drums can be tuned, but they are a little more finicky. To raise the pitch, the drummer has to heat the drum head, usually over a flame. To lower it, he has to get it wet. Each drum will change pitch differently when it is heated or gotten wet, so learning to tune a particular fixed-pitch drum is an art.

Making Noise

When a drummer strikes a drum skin, it makes a loud sharp sound followed by a rapidly decreasing tone. The sharp sound is called the attack, and it is made by a stick or hand banging into the hard surface of the skin, much like the sound your hands make when you clap. The strike also pushes the drum head downwards. Because the drum head is elastic, it springs back up again with a lot of energy, causing it to go up higher than the position it started in. This causes it to spring back down again. The drum skin goes up and down very quickly, pushing air in front of it and creating the tone, sometimes known as the decay. Some drums, such as the snare, have a sharp attack with almost no tone. Others, like frame drums, have a more mild attack with a tone that goes on and on.