How Does Sound Masking Work?
Sound masking is a specially tuned ambient background sound that targets the same frequency as human speech, reducing its intelligibility.
Sound masking does not cancel sound, but it makes conversations heard at a distance more difficult to understand, and thus less likely to distract.
Simply put, conversations that would normally distract someone at a distance of over 15 feet in the workplace will be notably less intelligible or noticeable. Face to face collaboration with fellow employees is not impacted, as conversations at a distance fade into the background and speech privacy is protected.
How Is Sound Masking Deployed?
Sound masking systems are installed by certified professionals specially trained in sound masking and acoustics. There are two main approaches to deploying sound masking.
Indirect Sound Masking
Sound masking can also be installed in an indirect position, in which the speakers are hidden above the drop ceiling and the sound masking is pointed upwards and reflected off the ceiling deck and back into the environment.
How is Sound Masking Different Than White Noise?
Sound masking is more comfortable and effective. Sound masking is often referred to as “white noise” but as you can see on the chart on the left, the sounds are very different.
Sound masking is specifically engineered to match the frequencies of human speech and to sound comfortable to the human ear. When implemented properly, sound masking should just fade into the background “hum” of a workplace.
Conversely, the frequency of white noise would be extremely irritating if it were amplified to a volume that would be effective for masking human speech — think of loud AM radio static.
Sound Masking Protects Speech Privacy
Speech privacy refers to the ability of an unintended listener to understand another person’s conversation.
When speech is hard to understand
or unintelligible – workers tend to not even notice it – it simply fades into the background.
When speech is easy to understand or intelligible –
it becomes very distracting. Overhearing conversations interferes with your internal monologue and makes it very difficult to concentrate.
Sound Masking Increases Productivity
Minimum productivity gain 1
Higher retention rates
Increase in ability to recall series of numbers 2
Increase in ability to recall spoken words 3
Brill, BOSTI Associates, “Disproving Widespread Myths about Workplace Design”
Haapakangas, Haka, Keskinen, Hongisto, “Effect of Speech Intelligibility on Task Performance – An Experimental Laboratory Study,” 9th International Congress of Noise as a Public Health Problem