What's Wrong With This Car?

Listen with the ears of an auto mechanic to interpret what problems exist in a new interactive exhibit, What's Wrong With This Car? at the Exploratorium in San Francisco. The exhibit, which includes the front half of a new car, encourages visitors to sharpen their listening skills by having them focus on sound as a source of information about an underlying problem, just as a trained mechanic does.

With practice, listeners can distinguish the auditory nuances that distinguish a sticking valve from a bad set of brakes. And they also hone another kind of skill: translating imitations of sounds, made by customers' lips and tongues, into the metallic clicks and whirrs of pistons, calipers, and cams. The exhibit, part of the just-opened exhibition, Listen: Making Sense of Sound, runs from March 1 to December 31, 2007.

Hood missing and engine exposed, the 2006 Toyota has been transformed into a combination detective story and audio experimentation station. Visitors press a button to hear one of numerous recorded driver complaints, such as "my car makes a squeaking noise when I hit the brakes," or "there's this clunking sound coming from the engine," accompanied by vocal imitations of the offending sounds.

Visitors search for the problem with a portable "listening stick." The car is sprinkled with tiny contact points. When visitors place one end of the stick against a contact, a real car sound-a squeal or clunk, perhaps a hiss or wheeze-plays from a speaker at the other end. It's similar to one way that real car mechanics diagnose sounds, using a metal rod to transmit, stethoscope-like, muffled sounds of a motor's internal workings straight to the fixer's ear.

When visitors hear the sound that they think caused the complaint, they press another button to hear Lisa Miller-a real San Francisco auto mechanic and consultant on the exhibit-explain the nuts and bolts behind the offending noise. Then they try again with another story of automotive woe. -- www.exploratorium.edu