Sound masking at the university level: far beyond the library.
A university campus is typically not a place associated with quiet or with privacy issues outside the campus library. Campuses teeming with students chatting while on their way to classes, classrooms filled with instructors and undergraduates verbally interacting, and boisterous student unions all come to mind.
The need for quiet on a college campus setting most often leads to the school library, where students typically conduct research and use the space to study. However, less often considered is the administrative functions of a university, where privacy issues can indeed come into play.
In industries like healthcare and banking, colleges are also legally bound to protect sensitive information. The Family Educational Rights and Privacy Act (FERPA) mandates that post-secondary institutions take all reasonable efforts to safeguard student information, including how the data is collected, stored, used, and released.
Many institutions have ramped up security measures, with some adding chief privacy officers to their IT teams to oversee the increasing number of compliance issues. While schools are doing a better job of ensuring students’ digital data stored on their server is protected, they may still be overlooking the need to safeguard student information during its handling and use. Sensitive conversations that may be overheard occur in the dean’s office, in the student health/counseling center, in the financial aid office, in the registrar’s office, in the campus safety office, and the campus bank. How can universities ensure that student privacy is protected?
Sound Masking can help ensure FERPA regulations are met by making it more difficult for people to overhear others verbally sharing sensitive information.
What Is Sound Masking?
Sound masking is making an active acoustic effort to veil unwanted sound waves—in other words, controlling noise to a positive end.
A typical example is using a white noise machine in an office setting, which provides just enough background sound so employees can focus on their tasks without being distracted by conversations happening around them.
When installed well, the sound-masking speakers are appropriately spaced, and the white noise is evenly distributed around the room. If not, people can be stuck in a too-hot spot where the artificial sound is loud and distracting by itself—or in a cold zone where it barely reaches them, and they can still hear others talking with enough clarity to be disruptive.
How Sound Masking Works
Sound comes in what is known as a “power spectrum.” Color terms are used to explain the differences in power between types of noise. The most commonly discussed and used in sound control are white noise and pink noise.
White Noise: White noise is sound energy that contains every frequency. Similar to how white light has all the wavelengths or colors of the visible spectrum, white noise holds a flat frequency in any bandwidth. This neatly compares to “black noise,” which has zero frequencies in a bandwidth—in other words, silence.
Because of its flat, all-encompassing frequency, white noise is often perceived as “staticky.”
Pink Noise: Pink noise has equal energy in all octaves. It has power in wide bandwidths, and each octave has an equal amount of noise energy. As a frequency increases, the power per hertz in pink noise decreases (whereas white noise stays equal).
Thus, lower frequencies in pink noise are louder, creating the perception of even and flat sound, which is often thought of as tonally softer and more soothing. Some research suggests pink noise can even have a positive effect on memory and sleep.
Both white noise and pink noise are used to apply a constant volume of sound to disguise unwanted noise. They each create an audible background of “shhhhh”—the universal “be quiet” gesture and natural defense against sound supremacy. However, sound generators can’t simply be plugged in and turned on. Properly designing a sound-masking system means controlling the artificial noise in a way that does its job without causing distraction.
Planar Loudspeakers To The Rescue
Sensitive campus spaces can be either built or retrofitted with planar loudspeakers to address problematic sound issues. These speakers make use of the solid surfaces already available in the space.
These loudspeakers use an immersive audio sound control system that harnesses planar wave physics similar to that of the soundboard of a piano or the body of a stringed instrument. The speakers turn any rigid, flat surfaces in a room—such as drywall, ceiling tiles, windows, or counters—into acoustic wave amplifiers that radiate evenly, providing a constant sound pressure level (SPL) across an entire listening space. These surfaces are readily available as they are the hallmarks of modern and popular industrial office design.
Because planar loudspeakers can equally radiate all frequencies across existing, rigid surfaces, they also help any intentional sound diminish at a shorter distance.
For example, students waiting in line at the registrar’s office can be standing closer to each other and not hear the personal information shared at registration. The planar loudspeakers reduce the sound much more dramatically over shorter space. The experience for others, then, is of hearing muffled sounds—they know that someone is speaking but cannot tell what they’re saying.
As the novel coronavirus (COVID-19) continues to see most faculty, staff and students working and learning remotely, this has been (and continues to be) a unique opportunity for facilities to take on important construction and upgrade projects. Sound masking is a perfect candidate. This simple installation can provide magnitudes of quiet effectiveness for decades to come.
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