Tube Chimes INTRODUCTION Percussion instruments produce sounds when they are struck, shaken, scraped, or crashed together. Some have a fixed note that cannot be changed, such as the triangle, cymbals, gong, or maracas. They are made from solid materials, usually metal or wood and, because the sounds they make do not involve vibrating columns of air, their sounds tend to be sharp and short-lived. Other percussion instruments, including the xylophone and tubular bells, are tuned to a particular pitch and can play octaves. A xylophone is also made from metal or wood—often a mixture of the two—and consists of a number of bars, arranged in a similar way to the keys on a piano. Each bar is made a specific length so that it produces a sound of a certain pitch. Short bars make high notes and longer bars make lower notes. MATERIALS 60" of copper tubing (any diameter) Broom handle Tape String Scissors 2 large nails Hacksaw WHAT TO DO 1. Using the hacksaw cut a length of copper pipe into 8 pieces (4", 5", 6", 7", 8", 9", 10", and 11"). 2. Lay the broom handle across the backs of two chairs. 3. Cut 8 similar pieces of string and tie the first to the broom handle. Take the shortest tube and use tape to attach the tube to the piece of string. Repeat this for the other tubes, trying to get them to hang straight and with their tops at the same height. 4. Strike to tubes gently with a long nail to make them ring. QUESTIONS 1. How does the length of the pipe relate to the pitch of the sound produced? 2. Can you make different sounds using objects other than the nails to strike the tubes? SOURCE "SOUND: Science Projects." Simon de Pinna, Raintree Steck-Vaughn Publishers: Austin, 1998, p. 36-37. © S. Olesik, WOW Project, Ohio State University, 2000. Print Version Sound Experiments Main Experiments Page Home