Paging is one of the most useful communications applications there is, even if it never makes the headlines.
Think of all the times when you use your paging system:
A school delivers everyday announcements over the PA. A business keeps all the employees up-to-date across its campus. A yoga studio pumps ambient music through nearly invisible ceiling speakers. A hospital pages doctors and nurses to let them know where they’re needed most.
Day after day, your paging system lets people hear what you need them to hear.
But what you probably haven’t thought about is this:
How can your paging system help people not hear what you don’t what them to hear?
Consider the sound masking speaker.
All that isn’t fit to hear
Sound masking speakers work by generating background sound that dulls the ability of people to distinguish words.
They don’t cancel noise, like some microphones do, because for noise cancellation to work, you need a very concentrated sample of sound. Noise cancellation works by filtering out particular types of sounds either mechanically or by using software.
Cancelling noise while someone talks directly into a telephone handset is very different than trying to develop an instrument that picks out unwanted noises from all the sounds in a room as people speak. With the former, you have a relatively clean spectrum of sound to work with. With the latter, all the echoes and conflicting sounds make picking out and eliminating any single thread essentially impossible.
Sound masking doesn’t cancel noise: it covers it.
There are two general reasons for why you might install a sound masking speaker:
- Reduce distractions
- Increase privacy
Reduce distractions
Offices can be chaotic places—even offices where everyone is pulling together. All the computers, printers, phones, visitors, and so on and so forth. You know how chaotic they can be.
On top of the chaos, there are always people talking. Conversations are part of the everyday fabric of officework. These conversations, so beneficial to the participants, can be seriously distracting for other employees.
You don’t want to stop people from talking and you can’t eliminate all the distractions, so what do you do?
Cover up the noise with a sound masking speaker.
Increase privacy
Sound travels.
But sometimes you want—or need—that sound not to travel. There are ways to do this. Dampening sound with insulated walls, carpets or even wall coverings can reduce noise. Those are costly, however, and could require renovations.
With plenums or returns, these sound-dampening techniques might not work, in any case. And those features, which are connected to many rooms, can carry sounds far.
Sound masking speakers can be mounted in the ceiling to cover up sounds that would otherwise be carried quickly and clearly to whoever is at the end of these spaces.
Health care practitioners, whose privacy requirements are often to do with regulations, are particularly interested in sound masking speakers.
How does sound masking work?
Sound masking works by filling up the sound spectrum with ambient noise that makes it difficult to pick out distinct sounds.
Why does that mask sound?
To answer that, let’s think about camouflage. One of the ways that camouflage works is by breaking up the outline of shapes. When looking at a camouflaged shape, the eye doesn’t have a distinct outline to tell it that a shape is a shape.
Consider the zebra.
A single zebra by itself stands out, but it’s very difficult to distinguish a single zebra in a herd of zebras. All the stripes blend together, and your eye can’t pick out a distinct shape.
It’s the same with sound. If you have ambient sound that doesn’t give your ear anything to focus on, it’s more difficult to pick out a distinct thread.
Picture a spectrogram. A single thread of speaking creates a distinct pattern of sound, which is what you’re hearing. Ambient noise creates a patternless expanse of sound.
Because your ear can’t pick out a pattern, sounds are masked.