Sounding Out Acoustics

Even for an acoustician, acoustics can be tricky. Yet ‘acoustics’ has been a buzzword in the workplace sector for some time now, with the benefits of controlled sound being recognised as a major factor in worker’s performance and overall well being. But where has this development stemmed from, and where might we see it popping up next? 

Gary Bevis, of UK company Screen Solutions, feels that the rise in interest and awareness of acoustics follows a trend, “of the ‘resi-mercial’ feel; of a softer and more comfortable office environment,” similar to that experienced in the comfort of one’s home. For whilst many now have the freedom that the combination of technology and more open and aware companies affords them in working from home, there are of course many that still work in more traditional office spaces; environments that are generally constructed from cold, hard and loud surface materials and by their very nature are shared by (potentially noisy) others.  

Gary is well placed to make such insights; his expertise sees him involved in the creation of 2D and 3D technical data, prototyping, production, building and testing of a vast array of interior acoustic solutions. And whilst he’s not an acoustician, his team work very closely with in-house acousticians to develop acoustic products for their own portfolio or for clients. Screen Solutions’ proven track record in the field of acoustics led to their acquisition by Danish fabric supplier Gabriel in 2016 and in doing so a seamless coming together of specialisms occurred, which offered an opportunity for the company to grow.  

But how do you even begin measuring sound and with it, figuring out how you can alter a space to improve the acoustics? Gary explains Screen Solutions approach:

“We have high quality sound measuring instruments that output complex graphs and allows us to determine if we are going in the correct direction.  

For instance, we recently developed a decorative acoustic wall panel called Kalm. Throughout its development we were able to test its effectiveness within real world environments. This meant that we could accurately calculate the performance of materials in relation to industry standards.”

But what does one use as a measure; what are industry standards based on exactly? Well this is where the acousticians take the lead, as Gary explains once again, “to solve the acoustics of an environment, acousticians have broken down their solutions into different categories which the industry refers to as the ABC and D’s.” Without meaning to sound like a science lesson, these alphabetical measures are simply explained as the following:

A - Absorption 

Absorption literally involves absorbing sound waves, usually using fabrics and foams. 

Imagine soft items - such as sofas, wall panels, cushions, hangers, baffles, ceiling islands etc.

That said absorbing products do not necessarily have to be soft. What’s important is that these materials soak up the sound energy that hits them rather than being bounced around the room, thus reducing the reverberation within the room.

B - Blocking 

Blocking means putting a stiff, dense physical barrier in the way of sound waves; stopping sound from transferring from one area to another.

This can be a wall, mobile screen, filing cabinet or even a desk screen to a certain extent. Typically the larger and more dense the blocking item the more effective it will be at preventing the sound wave moving past it. 

However, you need to be careful with blockers as they can also be considered reflective, which depending on their shape and use, can continue to bounce sound waves back into the location of the original sound source.

C - Covering

Also known as sound masking, this process involves covering an area with a layer of randomly generated sound to prevent over-hearing conversations, or to implement a level of privacy. 

This is regularly used in open plan offices where you may have two zones for two different types of work. If zone1 is a quiet working space and zone 2 is a collaborative environment where discussions take place this method works well. By adding a covering in zone 1 the volume in that space is essentially made louder, so when focused work is conducted there staff cannot hear those in zone 2 as easily.

D - Diffusion

This method involves scattering the sound waves from their natural linear pattern, which results in the sound being distributed more evenly through the room and reducing echo.

The benefits of using these methods in the workplace sector are apparent and it’s no surprise that staff concentration, retention and general happiness in the workplace have driven a very genuine desire to make spaces look, sound and feel better, but should it stop there? Should it only be our places of work, the profitability of which is ultimately measured by companies, not individuals that such efforts are made? Hospitality and healthcare are both sectors that are governed by the experiences of ‘the individual’, so could those kinds of environments benefit from more of a focus on their acoustics? Gary doesn’t see why not, “both sectors comprise of places where people meet, greet, relax, discuss, work or simply wait,” and therefore sound influences one’s experience of them.

But it’s not a simple one-size-fits-all scenario and there are perhaps more factors to consider with both sectors. When it comes to hospitality and entertainment environments, which are generally made up of hard surfaces and full of chatty people, it is often useful to control the sound by decreasing them. In this type of scenario absorption, blocking and diffusion are all viable options that allow for a comfortable ambient sound. But the opposite sometimes applies too:

 “When it comes to acoustic treatments it’s not always about making a loud room quieter, as you may need to a bar or restaurant. In certain situations you may need to increase sound levels within a room to achieve better speech privacy and a level of comfort. For example, if a doctor’s waiting room is too quiet, it can also be uncomfortable as you are easily disturbed by any other sound that may occur. You could implement diffusers within the room to have the sound waves bounce across the room more evenly or add a layer of sound cover (aka sound masking) to actively increase the sound level so people can have a quiet or private conversation in a different part of the room, without the fear of being heard on the other side of the room by the other patients.”

If we hope to continue to improve the experience of a varied mix of interior environments, across multiple sectors, it’s clear that that designers and acousticians come together, for as Gary explains, “designers work with their eyes and acousticians with their ears.” By combining these approaches our spaces of the future should look and feel better than ever.

The article was first published in The BCFA Dircetory 2020.