An Introduction to Technical Sound Masking

An Introduction to Technical Sound Masking

With evidence confirming that it takes workers up to 20 minutes to regain full concentration once distracted, the importance of acoustics are gradually becoming more widely known.

Sound masking is one of the many acoustic solutions available, yet people are still confused as to what sound masking is, how it works, and the logistics of sound masking in the workplace. 

Fewer sound blocking or absorptive materials are being used thanks to the demand for open-plan offices. And while these spaces enhance collaboration and communication, they very rarely aid or support concentration, thanks to the prevalence of hard, shiny surfaces, such as glass, laminate and marble.

Sound masking, however, can help improve the acoustic qualities of an office immeasurably. 

Sound masking introduces an ambient level of sound into various office spaces, specifically tuned and engineered to cover the same frequencies associated with human speech.

By including frequencies emulating the human speech curve, sound masking systems effectively cover speech around the office which means that the detail of conversations (and the distraction therefore) are inaudible.

Sound masking solutions are implemented into spaces in zones.A zone could be in the open plan area, breakout or reception, and is identified by its acoustic characteristics. For example, the ambient noise level in reception is usually lower than in the open plan area where you have more people chatting or on the phones.

In each zone, a tailored sound masking spectrum - that suits the room’s acoustics - can be applied, meaning you are less likely to even notice its presence yet still benefit from the acoustic comfort it’s providing.

It is good practice when designing acoustic solutions to treat the ‘sound at source’. However, due to the complexities and dynamism of today’s workspaces this isn’t always possible and when absorption soaking up sound at source isn’t adequate, sound masking implemented to cover stray noise is very successful. 

Sound masking should always be placed where the listener is, as opposed to where the noise is emitted from. A typical example of that of a private meeting room adjacent to an open-plan space – applying sound-masking in the open-plan area means any noise that does stray from the private meeting rooms will be covered and not deciphered by the occupiers in the open-plan.

Each zone is fully adjustable in frequency response and volume level and designed according to the ‘acoustic room response’.

This means that the environment in which the emitter is installed will be assessed, taking into account the materials constituting the rooms, and then the sound masking system is designed to perfectly counterbalance the acoustic characteristics within the room. Variances in ceiling heights or types could create sound level irregularities which can be solved by correct zoning.

One of the key benefits of Creatif’s ‘Humm’ sound masking system is that it uses SmartSMS-NET technology. Once installed and commissioned by acoustic experts, SmartSMS-NET has the capability to automatically adjust and equalise each zone throughout the day to ensure maximum effectiveness and acoustic comfort. This solution provides one less problem for businesses; a system that works autonomously to provide a continuously optimum acoustic environment.

Effective sound masking will reduce the radius of distraction to those sitting immediately around workspace users; beyond 5-7m speech becomes unintelligible. There are many ways in which sound masking can be applied, determined by the parameters of the workplace.

The sound masking spectrum is deployed through strategically placed emitters either in the ceiling void or close to the concrete soffit. In order to counter the negative effects of being in an open plan office, employers can introduce sound masking which will mitigate the risks of employees feeling like they have no privacy or are open to too many distractions.

Most masking technology works by pointing the speakers upwards, the sound hits the ceiling deck, which then reflects back down through the ceiling material and in to the workplace. This allows sound masking to permeate the entire workspace. Variable considerations include the ceiling configuration such as ceiling void height, pipework, ceiling tiles and absorbent materials.

An alternative method of sound masking is to create ambient sound with speakers installed under a raised access floor.

For example, the ceiling void is typically 762mm, however if the ceiling void is very low, at 305mm then the sound emitted by the speaker will need to be more focused and installed closer together to provide uniform coverage.

Other methods of deploying sound masking include installing speakers on a hard surface on the ceiling of the room. No bigger than the size of your palm, the speakers utilise the ceiling as a speaker board which diffuses the sound throughout the room. The flexibility of sound masking means that it can accommodate varying architecture with absolutely no difference in user experience.

Whether employees are in quiet spaces, breakout areas or service zones, the overall aim of sound masking it to make speech and common office sounds less intelligible and therefore less distracting. Discussions stay private, and businesses can remain compliant knowing that they’re not inadvertently breaching data security through overheard conversations.