Dec. 28, 2018
Classroom Theory Gets Real for CWU Physics Students

Six Central Washington University students studying acoustics recently had an opportunity to apply their skills in the real world.
The students, members of Andy Piacsek’s Physics 454 (Acoustics) class, studied how sound carries in the ballroom in the historic Elks Building in downtown Ellensburg. They were asked to measure how the room’s acoustics are affected by the presence of people and furniture and by installing carpet, curtains, and ceiling treatments.
The ballroom will be attached to the new 59-room Hotel Windrow, which is being constructed adjacent to the Elks Building. According to the hotel’s developers, a grand stairway in the hotel will lead to the ballroom.
Piacsek, who specializes in acoustics, said he was contacted by the hotel’s partners to determine what could be done to the space, which he described as a “very reverberant room,“ to make it most useful for different types of public events.
“We were asked to study how certain renovations could affect the acoustics of the ballroom,” he said. “They want to accommodate a variety of uses in the room, including music, lectures, or public performances.”
Steve Townsend, one of three managing partners along with Rory Turner and Paul Jinneman for the project, said his group has sought to develop partnerships with Central on everything it could. He said CWU President James L. Gaudino has been extremely supportive of the project.
“Last year, I was visiting the new Science II building on campus and had an opportunity to see the anechoic sound chamber [a room that absorbs all sound] and thought it was cool,” he said. “Then I learned that Central has an acoustics expert on the faculty and it occurred to me that maybe a physics class might be interested in getting involved.”
Townsend said he contacted the university, which put him in touch with Piacsek who has taught acoustics at CWU since 1997. He told Piacsek that he was interested in what could be done to the ballroom to improve its acoustics to make it more able to host events.
Piacsek said the first thing students did was make base measurements, or measurements of the room as it currently is configured, using balloons.
After pairing the students, he provide each team with a microphone and a digital recorder, then stationed them in different places in the room. A balloon was popped in two locations and each team made a measurement of the sound from its location.
Piacsek said the tests were conducted in mid-November, when the room contained 72 chairs, then repeated in late November without the chairs. This was done to see if the presence of furniture had an effect on the acoustics.
“We found it really made a difference,” he said. “It helped to illustrate for the students what it would mean to have an audience in the room.”
Piacsek said he developed a computer program to display the raw sound readings captured by the students, which was incorporated into the final report.
During the study, the students were paired and given specific tasks to measure. One team looked at the impact of having the ballroom’s hardwood floors covered with carpeting, another investigated the impact of having acoustic curtains to cover the windows and walls, while a third studied adding hanging acoustical ceiling treatments that absorb sound.
Using absorption data specifications provided by industry groups and associations, the students were able to calculate the impacts each material would have on the room’s acoustics, Piacsek said.
“Overall, this was a great opportunity for students to apply what they’re learning in the classroom on a real world problem,” Piacsek said, then added with a smile, “They also seemed to work harder on this than on some of their other projects.”
Townsend said he was impressed by the students’ professionalism and pleased with the results. He said his group will be adopting the study’s recommendations, which included adding a combination of the various materials to better absorb sounds.
“I think the students perception was that it was cool to get involved in something that provided hands-on experience beyond what they learn in a classroom,” he said. “It was a good experience for them and a good experience for us.”
The six CWU students involved in the study included: Jessica Kisner, Eric Kuhta, Josh MacLurg, Alex Mantilla, Jóse Mondaca, and Griffin Running.
In return for the preparation of the 12-page report, which was delivered to the Hotel Windrow partners in mid-December, the project developers plan to make a donation to the physics department research fund. The hotel is scheduled to open in the late summer of 2019.
Media contact: Richard Moreno, Department of Public Affairs, 509-963-2714, Richard.Moreno@cwu.edu.