The Sound of Silence - Y Magazine
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Works and Progress

The Sound of Silence

Physics professor Scott Sommerfeldt has created a noise-suppression system for fans of office equipment.

Scott Sommerfeldt

Scott Sommerfeldt | Photo by Annie Jones

How would it be to update a critical spreadsheet or type an urgent memo without the distraction of the cooling fan noise coming from your computer, copy machine, and desktop printer?

In an effort to make a quieter workplace, BYU physics professor Scott D. Sommerfeldt, ’83, has created a noise-suppression system that can reduce the whir of office equipment cooling fans to a soft whisper.

To quiet the ever-present noise of computer fans, Sommerfeldt and student assistant Kent L. Gee, ’01, used “active noise control” to pit noise against noise in an effort to create silence. They presented their success in building a low-cost, tiny system that incorporates the technology on May 25 at the annual meeting of the Acoustical Society of America.

Because sound travels through the air in waves of fluctuating pressure, opposite waves can cancel out the original sound, subtracting it from the air. Scientists use sensors, microphones, and computers to measure the unwanted sounds and then generate opposing sounds through miniature speakers.

The duo found that by using a four-speaker system that tightly surrounds the cooling fan, they were able to get a reduction in the overall sound of close to 12 decibels.

“That’s like going from soft talking to a low whisper,” says Sommerfeldt.

The components of the BYU system—speakers, cables, sensor, and computer chip—are relatively inexpensive. “We believe we’ve succeeded in creating a system design that not only works but is also cost-effective,” says Gee, who is currently pursuing a doctorate in acoustics at Penn State University. “Hopefully, that will lead to the development of quieter, yet affordable, products for the average consumer.”