The guide to a better soundscape

1. What is a soundscape? Simply put, the word soundscape refers to how we experience a given environment with our hearing. In recent years, the awareness of how everyday sounds affect us has grown steadily. This has been accompanied by an increasing interest in how design can be used to reduce noise and create better soundscapes. At Abstracta, we’re very pleased about this because we know how important soundscapes are – both to our well-being and to how well we perform at work. We’re also pleased to be at the forefront of innovation in this area.

We believe the future lies in perceiving an interior space holistically, as both a visual environment and a soundscape. Soon, designing furniture and interiors not only for our eyes but for our ears will be the standard.

2. The soundscape affects our well-being Office Inc.

Every day, we are surrounded by sounds that may negatively affect our well-being and cognitive abilities: chattering colleagues, email pings, phone rings, fans, and echoing footsteps. Too much noise makes us stressed out and fatigued. Studies show that noisy soundscapes decrease our cognitive performance by as much as 14 % – compared with how well we perform in harmonious environments. Often, the major cause of a bad acoustic environment is that the reverberation time – the time it takes for a sound to fade away – is too long in relation to the size of the room. This is a common problem in environments...

3. What is acoustics? Acoustics is the science of audible sound. The word acoustics derives from the Greek “to make oneself heard”

Definition of sound Sound is pressure waves in the air. The sounds have different characteristics because of differences in wavelength. They are defined as either short, middle, or long. The frequency of the wavelength is measured in Hertz (Hz). Low frequency waves have dark tones and high frequency waves high tones. Low frequency Long sound waves, dark tones such as vowels or ventilation-fans. 50 – 250 Hz Mid range frequency Mid length sound waves, mid tones such as normal speech. 250 – 2500 Hz High frequecy Short sound waves, light tones such as consonants and ringtones. 2500 – 12000 Hz

Sound loudness is measured in decibels (dB) When talking about good or bad acoustic in a room you can talk about two things – the noise level and the echo effect. The noise level or sound loudness is measured in decibels, (dB). A normal conversation is about 60 dB, a heavy vehicle is about 90 dB, and a commercial jet plane is about 125 dB. Pain Threshold Heavy vehicle Decidous forest

Acoustic products efficiency in decreasing the sound loudness The dB scale is logarithmic which means that a doubling of the sound intensity will result in an increase of 3 dB. A decrease to half of the sound intensity will result in a 3 dB reduction. Reducing the sound loudness is one obvious way to create a better soundscape. To decrease the reverberation time is another. Hanging absorbers 2 – 5 dB, Airleaf Floor screens 13 – 15 dB, Chubby Silent rooms 30 – 36 dB, Plenty Pod

Reverberation time The next step in the process of achieving a pleasant soundscape is to reduce the echo effect in a room, also known as the reverberation time. Smooth bare walls, floors, ceilings or other similar surfaces reflect the sound waves, and the sound bounces right back, causing a diffuse echo that is unpleasant. How to measure the reverberation time The reverberation time (RT60) is the time interval within which the sound level in a room has faded away by 60 dB. Typical reverberation times: a normal room: 0.5 s, concert hall: 0.8 – 1.5 s, church: 1 – 2.5 s. It is determined by how...

What reverberation times are we aiming for? Maximum reverberation time requirements for different types of rooms* Class rooms, lecture rooms, study rooms Conference rooms Educational landscapes Music rooms, drama rooms Craft rooms, technology rooms, utility rooms Dining rooms, restaurants, cafeterias larger than 100m2 Living rooms, staff rooms, offices, expeditions, libraries Corridors, entrances, copy rooms *Swedish Standard · SS 25268 Acoustics - Sound classification of spaces in buildings - Institutional premises, rooms for education, preschools and leisure-time centres, rooms for office work...

4. How to create better soundscapes The three primary methods of reducing the actual noise level and reverberation time in a room are acoustic absorption, diffusion and attenuation. Many of our products feature combinations of these methods, such as absorption together with diffusion, or absorption twinned with attenuation.

Absorption In this case, sound waves are absorbed by the surface, rather than bouncing off it, and are converted into heat energy. Generally speaking, porous or soft surface materials such as textiles contribute to sound absorption. Hard surfaces like glass or concrete reflect sound and thus create echoes. By using our absorption solutions, such as cloth-upholstered screens or wall panels that feature a sound-absorbent core, it is easy to balance the presence of hard materials, shorten reverberation times, and thereby create a more harmonious soundscape.

Diffusion In addition to the combination of materials that go into a piece of furniture, the structure or texture of its surfaces, and its shape affect ambient sound, as well. A hard surface that is also entirely flat will reflect sound directly, but one that is pleated or waved will weaken sound waves by dispersing them in various reflective directions. The effect is called diffusion. Using this method, sound waves are fragmented rather than broken down. By combining the method of diffusion with that of absorption, it is possible to create a harmonious soundscape.

Attenuation This method, also known as dampening, involves dividing a soundscape into discrete acoustic zones using different types of barriers that prevent sound from travelling unobstructed between, for example, two workstations. The most radical way of working with acoustic attenuation in an office space is to install silent rooms – such as Plenty Pod, which completely prevents sound from entering or exiting. Another way is to use screens. They can lower noise levels by up to 15 dB. Normally, office noise levels are around 65 dB, so a reduction of 15 dB is very considerable. By comparison,...