|LogiSon Acoustic Network||Booth 922|
LogiSon Acoustic Network
3-1050 Pachino Ct
Burlington, ON L7L 6B9
A sound masking system uses loudspeakers to distribute an engineered background sound throughout a facility, raising its ambient level in a controlled fashion. This new level obscures noises that are lower in volume and reduces the disruptive impact of those that are higher by minimizing the degree of change perceived by the listener. Similarly, conversations are either entirely covered up or their intelligibility is reduced, improving privacy.
The effectiveness of the masking sound is directly related to the system’s ability to closely match the specified curve—also called a ‘spectrum’—throughout the space in which it’s installed. This curve should be provided by an acoustician or independent party such as the National Research Council (NRC), rather than by a masking vendor.
The curve defines what the sound masking system’s measured output should be within the space. Regardless of how the system is designed or installed, the sound it produces is influenced as it interacts with various interior elements within the facility, such as the layout and furnishings. If the sound is to meet the desired curve, the system’s volume and frequency settings have to be adjusted in small, localized zones. In other words, it must be tuned for the particular environment in which it’s installed.
Tuning is handled by a qualified technician after the ceilings and all furnishings are in place, and with mechanical systems operating at normal daytime levels. Since conversations and activities can prevent accurate measurement, it’s usually done prior to occupation or after hours. The technician uses a sound level meter to measure the masking sound at ear height. They analyze the results and adjust the system’s volume and equalizer controls accordingly. They repeat this process as often as needed until they meet the curve at each tuning location.
A degree of variation from the specified curve is expected; it’s impossible to achieve perfection in every tuning location. However, because variations in the masking sound can profoundly impact performance, the specification shouldn’t only provide a target curve, but also a ‘tolerance’ that indicates by how much the sound is allowed to deviate from that curve across the space.
Historically, tolerance has often been set to ±2 dBA (i.e. plus or minus two A-weighted decibels), giving a range of 4 dBA. However, such wide swings in overall volume across the space can allow occupants to understand up to 43% more of a conversation in some areas than they can in others.
The LogiSon Acoustic Network is tuned using TARGET – a unique application that automatically third-octave tunes each small zone of one to three loudspeakers to the desired curve far faster and more precisely than formerly achievable, even by expert technicians. TARGET can achieve ± 0.5 dBA (i.e. a range of 1 dBA) or better, maximizing the benefits of the masking sound while reducing tuning time by 90% or more. It also generates a report verifying the final results. In this way, clients can be confident that they’re deriving the full benefit from their investment in sound masking technology.