How Sound Works and Instruments
How can you hear sound when you can't see it? Learn about vibrations, then build a variety of homemade instruments.
Sound is created by vibrations — a rapid, quick back-and-forth motion. You hear because vibrations travel through the air and reach your eardrum. Instruments make sound by vibrating the air around them at different speeds to create low and high pitches.
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1. What makes a sound?
Put your hand on your throat and say “aaahhh.” What do you feel? That movement is called a vibration — a rapid, quick back-and-forth motion.
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2. How do we hear sound?
We know the ear is what helps us hear — but which part exactly? It's the eardrum! Your brain uses the vibrations in the air that the eardrum detects and translates them into something you can hear.
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3. How instruments make pitch
Instruments vibrate the air at different speeds. Fast vibrations = high pitch. Slow vibrations = low pitch. Different sizes, tensions, and shapes change how fast the air shakes.
Build Your Own Instruments
You'll need
- Panpipes: 4–8 straws, tape
- Maracas: 2 plastic spoons, 1 Easter egg, filling (rice, beans, etc.), tape
- Harmonicas: 2 popsicle sticks, 1 sheet of paper, 2 rubber bands, 1 straw
- Korean drum: 2 plates, 1 chopstick, string, 2 beads, staples/tape/hot glue
Steps
- 1Pick which instrument(s) you want to build.
- 2Gather the materials for your chosen instrument from the list above.
- 3Watch the matching build video (linked below) and follow along step-by-step.
- 4Test your instrument — try to make high and low pitches by changing size, tension, or how hard you play.
- 5Build another one and put on a mini concert!
What would happen if you played the piano in outer space, where there is no air?