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Trial 1 - Rubber Bands and Vocal Cords

1. Try touching your throat when you speak or sing. Can you feel your throat vibrating?
   
   

2. Stretch two rubber bands around a plastic box. If the rubber band is very long, go around the tin can twice to make two bands across the top.



3. Start up the Sound Grapher.

   

4. Pluck the rubber band. Can you see it vibrate? Does it make a sound?
   
   
5. Put the plastic box over the microphone and pluck one of the rubber bands. Take a snapshot. Is it a smooth sound, or a rough sound?

   

   
   
   
6. Try pulling one rubber band tighter than the other. What happens to the pitch?
   
   

7. You can change the pitch by making the rubber band looser or tighter. Try playing a tune by changing how hard you pull on the rubber band as you pluck it.



8. Make one band tighter than the other. For each band, take a snapshot of the sound. Find the repeating pattern and count the number of times the pattern is repeated on the screen. Choose whether the pitch is higher or lower.
   

   Looser band, number of repeats:

   

   Tighter band, number of repeats:

   
   

9. Your vocal cords in your throat are stretched pieces of tendon, like rubber bands. They are looser when you sing a low note, and tighter when you sing a high note. Here is a picture of your vocal cords. The yellow part is your windpipe, which carries air from your lungs to your mouth.



10. Hum into the Sound Grapher. Change the loudness. What do you do to increase the loudness of your voice?
    
    
    
11. Hum into the Sound Grapher. Slowly raise the pitch, but don't get louder. The pattern in the Sound Grapher should stay the same height, and the repeating patterns should happen more often. Can you feel your vocal cords becoming tighter as you raise the pitch?
    
    
    
12. Make different vowels into the Sound Grapher to change the shape of the pattern. What do you do to change the kind of sound your voice makes?