Tangible Frequencies is an audio-visual performance by Natalia Escobar and Desiree Sauter. Commissioned by Arup for the international architectural festival “Make City” around the theme Resource City.

We took some walks around very loud areas in Berlin capturing sound and video, thinking, if sound vibrations generate frequencies and frequencies and vibrations are energy, could sound be converted to useful energy?

Doing some research on this topic we found that what the human ear perceives as clanging cacophony—the roar of a train engine or the whine of a pneumatic drill—only translates to about a hundredth of a watt per square meter. In contrast, the amount of sunlight hitting a given spot on the earth is about 680 watts per meter squared.

That’s not to say researchers aren’t examining ways to transfer environmental noise into electrical energy. Passing trains and subways aren’t only loud, but their surroundings rattle and vibrate as they pass. “There’s a strong interplay between vibrations through the medium that you hear through—air or water—and the physical objects around you,” says David Cohen-Tanugi, vice president of the MIT Energy Club. “It’s perfectly conceivable to absorb that movement and glean useable energy. You’re not going to power a city with it, but you can power small devices.”

Though still in the research phase, such technology could mean a new era in energy generation and conservation. “Harvesting acoustic noise is more about mechanical vibrations than sound itself,” says Cohen-Tanugi.

Sound is everywhere; whether we are at home in silence or walking through a city, we can feel it but we don’t see it. What would the world look like if all the frequencies around us would be visible? Sauter designed a program that captures vibrations, originating from the real world. Sound sources emanate their own frequency, which can be captured digitally and presented as visual abstractions. This is accomplished by using a computer program, camera and microphone; where the “event” being captured is affected visually by the auditory distortions the program hears.

The result of our project was a live audio-visual performance, a sound-image collage with the content of our walks, where you could see how the energy of the sound affected the image. The performance lasted 30 min; here is an excerpt from it.