How do you update an aging audio system in a historic space that just happens to be the largest classroom on the University of Iowa campus?

Last year, the Learning Spaces Technology (LST) team had to tackle that very problem after the team noticed an uptick in feedback about Macbride Auditorium: Students were having trouble hearing in the large classroom. That feedback sparked an in-depth assessment by LST staff who quickly identified an aging audio system as the culprit.

The system was about 30 years old and based on traditional loud horn speakers, with clusters of speakers in the ceiling and under the balcony, causing them to interfere with each other and distorting the sound produced by the speakers.

The planning process began during the 2018 winter break. Mark Mueller, a member of LST with an extensive background in audio engineering, led the project. The group consulted with specialized audio companies about how best to improve the space using a system that integrated into the lecture hall without dramatically altering its appearance. 

“We also worked with the Office of the Registrar and Facilities Management to ensure that the visual impact would be minimal,” says Tino Kaltsas, IT manager for LST. “We were in the auditorium comparing samples of speaker grills and fabrics to ensure it would match the space.”

The system installation also presented a challenge. Macbride Auditorium can seat 760 students and is over three stories tall. So, the team had to construct an elaborate scaffold, weighing almost three tons, to position the speakers.

“It took four weeks to complete the installation once the speakers arrived,” Mueller says. “We spent two days building the scaffolding towers and two days installing the wiring, including power. We had to go through two layers of brick, so we had to be creative with mounting the speakers.”

The new digital audio system of speakers, microphones, and amplifiers connect through a network to create a new and unique experience previously not possible with the older speaker technology. Engineers were consulted to calibrate the line array speakers so students sitting in the back of the room and in the balcony could hear sound as clearly as those sitting in the front. These audio changes have been positively received by both faculty and students.