ORONO – As sound is created by wind in the trees or a waterfall, a new art installation at the University of Maine’s Memorial Union is converting pedestrian motion to computer-generated “ambient music.”

Since May 26, visitors to the Union may have noticed variable electronic noises echoing and reverberating oddly from four speakers as they walk through the building. They may not have noticed a small surveillance camera on the ceiling, or that the pitch and tone of the sound changes with different types of motion – three people instead of one walking through – and even different colors.

Nate Aldrich, an adjunct new media faculty member who will teach classes in electronic music in the fall, and Zach Poff, who works in the film and video program at Cooper Union Art School in New York, are testing their latest artistic collaboration, “Observational Soundscape,” which will be up and active through June 25.

“A continually changing soundscape whose form and content reflect the visual and aural phenomena observed in the area” is how Aldrich and Poff describe the installation.

“The idea was to create a sound environment for a public space that reflects the movement in that space,” said Poff. “The idea is to treat it almost as an accompaniment of people in space and the movements that they make.”

Whether the result is sound, noise or music is in the ear of the beholder, but Aldrich and Poff’s ambient sounds respond spontaneously.

Poff and Aldrich wrote the computer program that converts information from the camera to sound. The system reacts to the amount of motion and also color, changing pitch, tone and timbre accordingly.

“If nothing happens, the system doesn’t do anything,” Poff explained. If, on the other hand, a class of visiting schoolchildren streamed through, the system would come to life to mirror the movement, and tones would likely become much more staccato and varied, the pair said.

The creation of ambient sound electronically from environmental stimuli is an evolving art form in new media, according to Poff and Aldrich.

“One can think of this as a convergence of two disciplines,” Aldrich said.

Poff and Aldrich presented a related performance last summer at the Ayers Island art festival, “Without Borders.” By training a camera on a musician’s hand movements, the motion modified the sound of the performance.

After the exhibit at UMaine, the artists plan to display the installation at Cooper Union Art School and then show it in public places in the United States and possibly Europe.