The sound enters your ears as you approach the trellis at the top of the bluff: a soft periodic plunk like pizzicato strings. The plunks grow more frequent as you follow the path toward the edge of Minneapolis' Minnehaha Falls, where a meandering creek that began at Lake Minnetonka plunges into a valley. Your steps are guided by an arrow on your phone's display screen.
You are on a "soundwalk," listening to music created expressly to accompany your surroundings. In this case, composer Scott L. Miller has created this soundtrack for your trek down Minnehaha Creek toward its terminus at the Mississippi River. The music changes as you get farther down the path, moods morphing as you cross bridges and pass landmarks.
This sonic journey comes courtesy of "SonAR II," Miller's mobile phone app that uses global positioning software to tailor sounds to your surroundings. What comes through your headphones or earbuds depends upon where you are in the park.
"SonAR" stands for "sonic augmented reality," and the app is available through the Apple App Store and Google Play. It allows you to experience an approximately 45-minute stroll down the creek and back, the sounds of nature interweaving with an electronic soundscape composed and recorded by Miller.
This is "SonAR II" because Miller created his first "soundwalk" at St. Cloud State University, where he's a music professor.
"I was working with the Visualization and Simulation Lab at St. Cloud State on virtual reality projects," Miller said from his home in Otsego, Minn. "They also introduced me to augmented reality. And one of the first things that came up was having GPS tracking so you could have these virtual 'speakers' located anywhere in the world, and, as you get close to those speakers, you can hear them. I started experimenting with those."
When Miller received the Hellervik Prize from St. Cloud State — an award designed for faculty members to pursue interesting projects — he knew that he wanted to use the funding to create a soundwalk. While he dreamed of more exotic locales, COVID-19 placed constraints upon travel. It was his daughter who suggested Minnehaha Park.
"I said, 'OK,' and went down and did a soundwalk — a listening walk, really — where I took notes and just listened and recorded the sound of that trail and some other parts of the park," Miller said. "And then I spent time listening and thinking about what I was hearing, what kinds of sounds really dominated the recordings and created what in acoustic ecology would be called a 'keynote,' a sound that is often equated with the tonality of a given acoustic environment. In the park, it's really water more than anything else.