Engineering alumnus brings musical road to Auburn’s campus

Tim Arnold, an Auburn University alumnus, had the idea to put America’s newest musical road on the university campus.

“The concept is really kind of complex and simple at the same time,” said Arnold, who received an Auburn industrial engineering degree in 1994. “It’s reverse engineering the physics of sound.”

The section of South Donahue Drive is dubbed “War Eagle Road,” as it plays part of Auburn’s fight song, “War Eagle.” Drivers, operating a vehicle at 35 mph, experience the first seven musical notes as they head toward campus.

A musical note is simply sound vibrations at a particular frequency. An ‘A’ note, for instance, vibrates at 440 Hz per second. Arnold used the speed limit and the frequency of each note to determine how often a material would appear in the roadway to make the right sound.

“It’s that place where science meets art,” Arnold said of the musical road. “I hope it puts Auburn in that Cult Americana of the other roads.”

This is the third musical road in the United States, but the first on a college campus. Other musical roads—in Lancaster, California and New Mexico—use grooved pavement to create the vibration and subsequent sounds. Arnold said he “built a better mousetrap” by using a DOT-approved surface application that lies virtually even with the roadway.

“I’d heard of other musical roads, but when we wanted to do one here, we wanted to make certain improvements,” he said. “We hope it’s safer, more durable, better sounding and, of course, non-destructive to the road.”

Arnold credited his Auburn education for his ability to analyze the situation and develop an improved musical road. “That was all about my engineering degree,” he said.

War Eagle Road is the first musical road with the surface application material, the first on a college campus and first with a fight song. Lancaster’s roadway plays “The William Tell Overture,” while the section of Route 66 in New Mexico plays “America the Beautiful.”

With the support of Chris Roberts, dean of the Samuel Ginn College of Engineering, Arnold assembled a team of faculty and students, including Eldon Triggs, Maria Auad, Jeff Thompson, Edmon Perkins and Alex Tucker, to name a few, from chemical, mechanical, polymers and aerospace engineering to assist making the idea a reality.

“The idea was cool enough for people to say yes,” said Arnold.

The team tested the product on an auxiliary road at Auburn’s National Center for Asphalt Technology. The initial runs tested material at 45 mph, which, at the time, was the speed limit on South Donahue.

When the road was changed from four lanes to two lanes with a center turn lane and added bike lanes, the speed limit was reduced to 35 mph. Arnold recalculated the math based on the lower speed and tested new pieces.

With new calculations and testing completed, 36 pieces were produced and cut. Arnold and colleagues from Facilities Management and engineering helped adhere the pieces to a section of the northbound lane on Oct. 24.

One sign reminds drivers of the speed limit; another sign thanks the College of Engineering for its support.

“It sounds best at 35 mph,” Arnold explained. “If you go faster, it’s just going to be higher pitched and shorter. It’s almost like spinning a record needle faster or dragging your finger and slowing it down. If you go below the speed limit, it’ll be a low hum. But, reverse engineering the math makes people drive at 35 and other musical roads have been shown to sort of induce participation. People want to drive at 35 so that they get to hear the musical road.”

Hearing the musical road is a bonus for traveling the roadway safely, at the posted speed limit.

Arnold said he has already worked out the math for a musical road featuring “Glory Glory to Ole Auburn.”