Sound masking systems have been available for decades and installed in many hundreds of millions of square feet of facilities worldwide for companies ranging from small business to Fortune 500. They’re also increasingly being used in new applications such as hospital patient rooms. However, few people are familiar with this technology or how it works.
Here’s why sound masking is essential to speech privacy and noise control:
Sound masking reduces dynamic range (i.e. the difference between the background sound level and peak volumes). Our senses are attuned to changes in our environment, making it very difficult to disregard them. By raising the background sound level in a controlled manner, this technology dramatically reduces the number and magnitude of these changes. Noises beneath the masking are imperceptible. The impact of those above it is lessened.
Similarly, our level of speech privacy depends on the signal-to-noise ratio or the volume of the speaker’s voice relative to the background sound level. The greater the voice’s volume relative to the background sound, the more noticeable and intelligible the conversation. While sounds decay in volume over distance, low background levels mean that they can be clearly heard from afar. Sound masking dramatically reduces this distance.
Sound masking also addresses the acoustic variations found within all facilities, which can be due to the type of ceiling, open air return grilles, HVAC equipment, proximity to walls and office equipment. Variations in lighting and temperature are kept within comfortable parameters and, similarly, sound masking minimizes variations in both sound volume and frequency by introducing a specific background sound at controlled levels across the space.
Using sound masking can also help support sustainable endeavours, especially when included in the project’s design stage. For instance, sound masking increases noise isolation in open areas. Natural ventilation can be employed without affecting speech privacy and the amount of disruptions occupants experience due to noise. It can also support using demountable wall systems. Adding it is comparable to increasing their Sound Transmission Class (STC).
Sound masking is easy to retrofit. However, planned incorporation during design can eliminate the need for extra insulation or layers of drywall, plenum barriers, and high-spec or permanent walls around private offices, reducing costs and maintaining the flexibility of the space for future renovations. In open plans, it helps maintain acoustic control as density increases or workstation partitions are lowered. This technology also reduces the requirements for other treatments, though a balanced approach to acoustic design is always needed. It provides paging and music functions, eliminating the need for a second system to be installed.
LogiSon Acoustic Network specializes in providing sound masking solutions and is headquartered in Burlington, Ontario. For more information about sound masking and how LogiSon can improve the acoustic qualities of your building or office, please contact us. Tel 905-332-1730 or 1-866-LOGISON (1-866-564-4766) and visit us at www.logison.com.
About the author
Niklas Moeller is vice-president of LogiSon Acoustic Network. He also writes a blog called “UnMasked – an inside look at acoustics” at www.soundmaskingblog.com.