Big Ears

What It Is

Over-ear stereo headphones with funnels and PVC attached.

What You Do
Put on the headphones. Now, turn your head from side to side, and listen to the world around you. The headphones enhance your ability to locate sounds.

What You Learn

You locate the source of sounds by detecting the time difference between sounds arriving at your right ear and your left ear, as well as by the difference in intensity—you'll get a bit more intensity in your near ear.
The time difference is much more sensitive. If you collect sounds with forward-facing ears, the intensity in both ears is the same, so you locate sounds with the time difference. This is more sensitive, so you end up being able to much more effectively locate the source of sounds.
There's a cost, though; you can't hear sounds from behind you as well! So animals—think coyotes—who hunt have ears that point forward. Good for locating prey! But prey animals—think horses—have ears that collect sound from all around. You can't tell where the sound is coming from as well, but you can hear things on all sides.

How You Make It


What We've Learned


DIsplay Sign Text

What to Do: Put on the headphones with the funnels attached to them. Now turn and face different locations around the room. You should be able to focus in on sounds across the room, and hear them very well!
What is Happening: You may have noticed that some dogs and other animals have ears that look like funnels. Their ears will collect sound just like a lens collects light, which allows them to hear distant sounds - and since their ears point in one direction, they can pay special attention to the sound coming from one direction. Just like you can with these special ”ears”!!!

Related Projects

Chronophones, Ear Guitar, It's All in Your Head, Oven Rack Organ

Learn More About Us

We are the Little Shop of Physics, a hands on science outreach program at Colorado State University. Check us out!