As with any type of product, you probably assume there are differences between sound masking systems. And you’re right. But maybe you’re not aware of just how substantial these differences are.
Every sound masking system introduces a sound into a space, but there’s very little similarity in terms of how they’re engineered. It’s crucial to be able to identify – and differentiate between – types, because this information immediately tells you a lot about the performance you can (or can’t) expect from a particular product.
Of course, this begs the question, ‘What’s the best way to categorize sound masking systems?’ And there are many suggestions out there.
Some vendors focus on how the loudspeakers are installed: ‘Our next generation technology uses loudspeakers installed in [fill in the blank]!’ This definitely isn’t the right basis for categorization. Loudspeakers are the delivery element – the component that feeds the masking sound into the space. While their placement and performance are important (in ways we can explore another day), almost any type of sound masking system can use loudspeakers installed in a variety of ways: above-ceiling and upward-facing, downward-facing and cut through the ceiling, wall-mounted and more. Mixing and matching of loudspeakers has been done for decades and often even within the same facility. So, it’s not the way to differentiate between types.
The right method to distinguish between sound masking systems focuses on their electronic design or ‘architecture,’ because this has the most profound effect on a system’s performance and isn’t something that can easily be changed (unlike the loudspeakers’ installation).
There are three types of architecture:
Some might argue that there’s a fourth type – standalone desktop devices – but these aren’t professional quality systems and are rarely used as commercial solutions.
The centralized system was the first to be introduced, around forty years ago. While there have been minor changes to how these systems are implemented (for example, a shift from analog to digital controls), their design and performance are still pretty much the same as they were decades ago. The ‘centralized’ name comes from the fact that the electronic components used to generate the masking sound, as well as to provide volume and frequency control and amplification, are all located centrally within a facility (in an equipment room or closet). The settings established at this central point are broadcast over a large number of loudspeakers, usually dozens to hundreds in a ‘zone.’ While most offer some very limited analog volume control at each loudspeaker, their centralized design means that large areas of the facility are nonetheless served by a single set of ‘averaged’ output settings with little or no option for local adjustment.
The decentralized system emerged in the mid-1970s. I’m well acquainted with this type because our company spent decades driving this technology forward with our SCAMP® Sound Masking System. In decentralized systems, the electronics are integrated into some of the loudspeaker enclosures (in the case of the SCAMP system, these were called ‘Master Units’) and distributed throughout the facility – hence, the ‘decentralized’ name. The number of loudspeakers in each ‘zone’ is much smaller than centralized systems – ranging from 1 to 3 maximum – and there’s also fine volume control within each one. Though local control is much better than with centralized approaches, there are still limits to the adjustments that can be made, specifically with respect to frequency.
These were the only two choices until the introduction (by our company) of the first networked sound masking system in 2003: the LogiSon® Acoustic Network. This technology uses the benefits of decentralized electronics, but networks the system’s components together throughout the facility – or even across multiple facilities – in order to provide centralized control of all functions. Networked technology offers many advantages over either of the previous types. Whereas centralized and decentralized systems require technicians to access the ceiling to make local adjustments at the loudspeaker, with a networked system absolutely all control is handled centrally from below the ceiling (via a small control panel or PC software). Adjustments are easy, quick, precise, reportable and repeatable. Networked systems also provide vastly greater adjustment capabilities, with far smaller zones than central systems and a greater number of controls than decentralized systems. And they offer functions that are impossible to implement with either older technology: digital zoning, monitoring, programmable occupant controls, and more.
So, when you’re looking at purchasing a sound masking system, determine whether the system’s architecture is centralized, decentralized or networked. Vendors who try to get you to focus on the way the loudspeakers are installed or on a particular feature probably don’t want you to pay attention to the electronic structure of their system...likely because they’re the simplest, least flexible and most out-dated.
In fact, just today I read on a vendor’s website that the ‘newest generation’ of sound masking is based on a single volume control function! Right. Other masking systems have previously included (and, in our case, long abandoned) this particular feature...which, in this case, is offered with a centralized system.
And that’s the risk of focusing on the wrong basis of distinction. You might be persuaded that a system is the latest technology whereas it’s really just a simple variant of one of the two earlier system types described above.
Being able to properly categorize a sound masking system won’t tell you absolutely everything about what the system can or can’t do, but it’s the best place to start!