Learn how to make the most annoying sound in the world – all you need is 2 empty drink cans.

WARNING: This sound is dangerously powerful, and with great power comes great responsibility!

You’ll need

  • 2 empty soft drink cans
  • A big breath of air

What to do

  1. Very lightly hold one of the cans the right way up, with the bottom rim of the can resting on your thumb and your middle finger holding the top rim of the can.
  2. Hold the other can the same way in the other hand.
  3. Bring the 2 cans together until they are almost touching.
  4. Blow as hard and fast as you can through the gap between the cans. This should make a high-pitched squealing noise!

Questions to ask

Did you hear the sound? If not, try moving the cans closer together or slightly further apart. Make sure you are holding the cans gently by the rims with your fingertips. If you hold the bodies of the cans, your fingers will stop them vibrating properly. It can be tricky!

Try using cans of different sizes. How does this change the sound?

Try filling the cans with different materials, like water, cottonwool or sand. How does this change the sound?

What's happening

Blowing between the cans makes the air between them move very quickly. This causes the 2 cans to bounce against each other very fast, and they begin to vibrate. The small sound made by these vibrations is amplified, or made louder, inside the cans – this is the high-pitched sound you can hear.