Sounds are all around us. Understanding how sound is produced makes it possible for us to manipulate it so we can decrease the number of unpleasant sounds created by things as diverse as airplanes and vacuum cleaners.
Sound is caused by a movement or vibration created by force. Some vibrations cause air to move, to create sound waves that we can hear. The pitch of the sound (how high or low the sound is), depends on how fast an object vibrates. The volume (how loud the sound is), depends on the degree of force used to make the object vibrate. When we increase the volume of a sound we are amplifying it.
With drums, we strike the skin to create a sound. The force that causes the vibration is the blow on the drum. The harder we strike, the louder the sound. You can manipulate the pitch of a drum in three ways: 1) tighten the drum’s skin to make the pitch higher; 2) put a thicker skin on the drum to lower the pitch; and 3) strike the drum closer to the center to produce a slower vibration and lower pitch, which sounds more resonant.
1 & 1/2 hours (allow at least 1/2 hour for design)
Discuss how force is needed to produce vibration and how different kinds of vibrations produce a variety of sounds. Demonstrate how force is used to make drums vibrate.
Drums can be made with just about anything. Using the materials provided, design a drum.
Various cultures throughout the world use drums as a way to communicate. Drum beats can signal warnings or transmit elaborate messages, much like Morse code, as long as the person receiving the message is within earshot. Have the students design their own drumming code so that they can send secret messages to their classmates.
Drums have been used throughout history for religious, spiritual, technical, musical and recreational purposes. Have the students identify the types of drums used by their own culture and share the story of these drums with their classmates. They may even want to tell their story while beating a rhythm on a drum.
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