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!