Montshire Minute: Hear Here Exhibit

Originally aired during the week of January 6, 2003

Monday

Want to make waves? Then bang that drum, strum that guitar, or blow that horn. Wait a minute. You can make waves with musical instruments? You betcha - when you make music, you are creating sound waves. And making music is just organizing and combining those sounds in a pleasing way. Throw a rock into the calm surface of a pond and you make waves of a different sort. The ripples travel outward, in tiny watery peaks and valleys. Sounds make waves in the air. When the sound waves reach our ears, our eardrums are agitated and our brains sort out for us the sounds we are hearing. When we hear a passage from a symphony, or a bunch of wailing guitars, we hear the tones all blended together to form a musical pattern. In honor of a new exhibit at Montshire called Hear Here, we'll investigate how musicians make sound this week on our program.

Tuesday

Beauty is in the ear of the listener. We may not agree on what kind of music sounds best, but all music has this in common: it comes in waves. Put your finger lightly on a loudspeaker and you will feel the vibration. If the music is producing low bass tones, you may even be able to see the speaker moving! What you are witnessing is the compression of air. Some of this air flows outwards, compressing the next layer of air. The disturbance spreads out as a travelling sound wave. Finally the sound wave causes a small vibration in our eardrums. Musical instruments produce different kinds of disturbances. As they strike our eardrums, these waves of air pressure are translated in the brain into recognizable sounds: a guitar, a violin, or a bongo drum. All good vibrations!

Wednesday

Music comes in many forms. There's Jazz. Country. Rock. And "elevator." The sound of music is caused by vibrations, and the movement of sound is described as a wave. Think of the kind of wave you see in a football stadium, when fans stand up in one section, wave their hands over their heads, and then sit back down again. Then, people sitting next to them take their turn standing up, waving, and so forth. The spectator sees a "wave" rippling through the entire stadium. An awesome sight, huh? In this case the crowd is the medium through which the wave passes. But none of the participants are moving from one section to another - they are only leaving their seat long enough to wave and sit back down again. Sound moves in the same way, passing through the medium of air until it reaches our ear.

Thursday

In honor of a new visiting exhibit at Montshire called Hear Here, which opens January 11, we've been investigating how musicians manufacture sound. Music begins with vibrations that are created by bodies in motion. When the clarinet player blows into his mouthpiece, he sets a small elastic reed in motion, producing a column of vibrating air. By opening or closing the holes along the instrument's shaft, he is constantly adjusting the length of the air column. If the instrument is shorter, the note produced will be high in pitch - if it is longer, the note will be lower. A longer tube is needed to play very low notes, which is why instruments like the tuba need to be curved in shape. If all the curves in the tuba were uncoiled and straightened out, the instrument would be too long to play!

Friday

Music is all about good vibrations. The more vibrations there are per second, the greater the frequency. And the greater the frequency, the higher the pitch. In a violin, the quality of sound of a string depends on its thickness, its length, and how tightly it is strung. Long, loose, heavy strings vibrate more slowly than short, tight, light ones. In the violin the strings get thicker and the pitch gets lower as you go from E to A to D to G. The musician can change the frequency of a string by adjusting the tension. She does this by using the tuning pegs on the violin. The tighter she makes the string, the higher the pitch her instrument produces. Be sure to stop by Montshire this winter and find out more about how we make and perceive sounds with Montshire's new exhibit Hear Here, Listening with Eyes and Ears.