Last year, Northwestern Radio/Television/Film lecturer and MA in Sound Arts and Industries faculty member Stephan Moore spent several months in Australia working on a project related to sound design and the impact of highway road noise. An expert in environmental sound design, Moore worked alongside colleague Jordan Lacey, a postdoctoral fellow in the School of Architecture and Design at RMIT University, an Australian public research university in Melbourne.
The project – and subsequent research paper that Lacey and Moore presented at the Invisible Places conference in April – is called “Acoustic design innovations for managing traffic by cancellation and transformation.”
Lacey, the principal investigator, crafted the project proposal and approached Transurban, a company that builds and maintains highways and tollways. The project was eventually funded by the Transurban Innovation Grant. Lacey also assembled the team of experts in acoustics, sound art, and sensory ethnography that realized the research.
“The roads [Transurban] builds often cut through existing neighborhoods,” Moore says. “Inevitably, they end up dealing with highway noise complaints from residents.”
The basis of Lacey’s research is twofold: First, he wanted to use noise-cancelling technology and employ a row of mics and speakers to counteract noise directly. Second, he wanted to take the noise and convert it from disruption to artistic experience.
“I ended up becoming the lead sound designer for creating sound systems that would transform it to an artistic experience,” he says.
Moore came up with transformative methods in the lab, employing two primarily: resonant filtering and analysis/resynthesis. Resonant filtering involves applying pitched resonant filters to the incoming signal, resulting in tonal and melodic manipulations of the highway noise. Analysis/resynthesis includes using pitch-detection algorithms to extract any prominent pitches from the highway noise signal, and then using simple oscillators to produce pitches to match and harmonize with the highway noise.
“We were all pleased with the success of these transformation strategies in this initial round of research. I think everyone ended up feeling like there was a lot of potential,” Moore says.
The use of sound-cancellation technologies proved more difficult. Moore elaborates, “It was a privilege to see what a state-of-the-art best try would be and to appreciate how difficult and expensive such a system would be to implement. There is still potential for these technologies to play a role in future research, but we experienced a more immediate impact with the transformation approach.”
Another encouraging result from the first phase of the project, according to Moore, was the reaction ethnographers collected from the surrounding community.
“The ethnographers’ overall finding was that people responded positively and they would at least be interested in living with the transformation part,” Moore says. “They don’t want to have music pouring out of the highway at them, but if it were kept at a level that matched the level of traffic, that would be something that could make a lot of sense to install in their communities more permanently.”
Moore and Lacey hope Transurban will see the value in the research and provide further funding for a second phase, in which researchers could build a more permanent site along the highway and sound designers could work on other methods of transforming sound.
Read more about our faculty member Stephan Moore here: https://sound.northwestern.edu/faculty/StephanMoore