1. The qualities that determine the ability of an enclosure (such as an auditorium) to reflect sound waves in such a way as to produce distinct hearing –> the one definition I associate with acoustics
2. A science that deals with the production, control, transmission, reception and effects of sound
Noise can be damaging to your health, with consequences reaching far beyond just ear damage, but it is also one of the main causes for lack of productivity in the workspace.
The acoustical needs of a space will depend on its purpose; for example speech privacy is important in an open office setting, while confidentiality is important in a doctor’s office. The acoustical needs should be part of your thinking from the design phase onwards. Doing so will allow you to keep the costs down, maintain the intended aesthetic and give you more product options by not having to remedy the situation after the project has been completed.
4 important acoustics concepts:
Reverberation = the prolongation of sound caused by continued multiple reflections, meaning it will take some time for a sound to become inaudible once it has stopped emitting energy. It is affected by the size of the space and the amount of reflective and absorptive surfaces. –> when listening to music in a concert hall, you want a high level of reverberation, but in an open office setting you will want just the opposite.
Reverberation Time = the time required, in seconds, for the average sound pressure level in a room to decrease 60 decibels after a source stops generating sound. In an open office setting, where reverberation time is very important, it should be 0.75 seconds.
Reflections = the way sound strikes a surface before reaching the receiver. –> is caused by the shape of the space (domes and concave surfaces will have a high reflection) as well as the materials on the surface.
Noise Reduction Coefficient = a single-number index for rating how absorptive a particular material is.
Sound Transmission Class = a single-number rating of a material’s barrier effect. The higher the number, the more efficient for reducing sound transmission.
Acoustics is a mixture of reverberation, reflection and absorption, and to reach an optimal level, there should be a coordination between the following components:
Sound will travel up and will be reflected back down into the office space unless the ceiling absorbs as much of that noise as possible. Soundproofing can be done by using specific panels in the ceiling which will absorb the noise from the office floor below.
Even light fixtures will have an impact based on their shape: flat and lensed fixtures reflect sound spectacularly and should be avoided; parabolic fixtures are preferred because they will scatter the sound.
Wall and floor treatments:
Carpets will provide a minimal level of absorption
Individual work stations should be positioned relative to columns, walls and each other to avoid uninterrupted sound paths between work stations. Gadgets such as copiers, printers which make a lot of noise should be located in a separate room.
Furniture and furnishings:
Tack boards, filing cabinets… will degrade the absorption properties of the main materials. Electrical raceways, unless treated, will also diminish the effectiveness of the barrier and its absorptive properties. Open areas in the barriers to let wires pass…should be avoided as much as possible.
All vertical surfaces, such as dividers between desks, are sound reflectors unless specifically treated. Hard, flat and smooth surfaces will be the most reflective, so make sure to make them in absorptive materials. A special, impermeable division can be added to the center of a barrier to make it more effective.
Barrier height should be above 60″ but below 80″ to have the best effect.
Masking sound system:
They provide ambient background sound that reduces exposure to distracting office noises by emitting a discreet, electronically-generated sound through specifically installed, unobtrusive speakers.
15% of new office buildings these days are equipped with masking sound systems, which should be hidden in the ceiling to be most effective. This way, employees won’t even be aware of the pink noise.