Star Wars Science: Experiment 1

Star Wars Science: Experiment 1

Be Han Solo with a homemade blaster sound effect

Luke Skywalker may have the Force, but Han Solo is the coolest Empire-battling hero in the galaxy.

Space pirate, rebel, scruffy looking nerf-herder... He's all this and more! Not only that, but Han is a dead shot with his handy laser blaster.

At Planet Science we are celebrating the news that Disney is planning to release some new Star Wars films over the next few years. This week's experiment means that you can learn how to make your own blaster sound effect with nothing but a metal slinky and a paper cup.

We'll look at the science behind the sound effect too, but first enjoy some clips of Han Solo at his very best (courtesy of Lucasfilm).

The original blaster sound effect was created by Ben Burtt, sound designer on the Star Wars and Indiana Jones films, WALL-E, the recent Star Trek movie and more. He made the effect by hitting the thick cables that held up a radio antenna. The cables vibrated to give that great "pe-ow, pe-ow" sound.

How to make you own blaster sound

Assuming that you don't have a radio antenna in your back garden (and even if you did, hitting it isn't a great idea) then you can use a metal slinky and a paper cup to get the same effect. A large plastic yogurt pot will also work.

First, get the cup and push it into the top of the slinky coil. Now hold the cup in place, holding onto to only one or two of the coils so the rest can move.  Pick up the slinky and cup, one hand underneath the slinky, and stand up with your arms outstretched. Let go of the bottom of the slinky so that it stretches toward the ground and enjoy your blaster special effect.

Check out this video clip to see a demonstration.


How does it work?

When the metal coil stretches it vibrates.  That vibration makes the air around the slinky vibrate as well.  As the vibration (or sound wave) travels outwards it gets to our ears.

Let's talk about our ears for a moment...

The outer part of the ear (the pinna) is the bit that sticks out from your head.  It catches the sound waves and channels them into your ear like a funnel.

When the sound gets into the middle of your ear it vibrates the drum (a tightly stretched piece of skin) which then moves some tiny, delicate bones called the hammer, anvil and stirrup.

These help move the sound further into the ear to the cochlea.  Here the sounds are turned into nerve signals that get sent to your brain.

You can find out more about how your ears work by clicking here.

So, back to our slinky-powered blaster...

How do we get that lovely "pe-ew, pe-ew" sound?  Well, it happens because not all sounds travel at the same speed.

When the bottom of the slinky hits the floor, waves travel back up the coil.  However, the higher sound (let's call it the pe-) travels faster than the lower (the -ow).

This means that the higher sounds gets to our ears first, followed by the lower, and we here pe-w, almost like two separate sounds.

Clever stuff!

So, what is the cup doing?

Very simply, the cup is making the sound louder (amplifying it).  This happens because the coil vibrates the cup which has a large amount of air in it.

More air to vibrate = more powerful sound waves travelling through the air towards your ears.

And there you go - physics and biology working together to help Star Wars fans everywhere live their dream of being Han Solo (or maybe even Chewbacca).

May the force be with you!