Archive for category Offices
Posted by Acoustics First in Absorption, Art Galleries, Articles, Auditorium, Broadcast Facilities, Diffusion, Home Entertainment, Home Theater, HOW TO, Industrial Facilities, Media Room, Multipurpose Rooms, Music Rehearsal Spaces, Offices, Product Applications, Recording Facilities, Studio Control Room, Teleconferencing, Theater on April 29, 2022
For the May 2022 edition of “The Construction Specifier,” Acoustics First was asked to illustrate the use of absorption and diffusion in creating optimal acoustic spaces. The article is a great reference for understanding the types of acoustic absorbers and diffusers, as well as some use scenarios like offices, critical listening spaces, and larger communal spaces.
Note: This version has been edited and the advertisements are removed. The full published version of the May 2022 digital edition can be found on The Construction Specifier’s website here.
Glass is a universal building material that is attractive to architects and clients, while posing a variety of challenges to acousticians.
Due to its transparent nature, glass creates an open and pleasing atmosphere. Curtain walls, skylights and windows allow for a view both outward and inward; connecting occupants to the building’s natural or urban setting. The use of natural light can lower electricity bills, brighten the rooms of a building, boosting the mood of the occupants. Glass is also a renewable building material, with 30% of new glass comprised of recycled materials. For all these reasons and more, glass will continue to play a major role in architecture in the future.
However, glass has a number of acoustical properties that can contribute to a poor occupant experience. To illustrate this, let’s take a closer look at what happens when sound interacts with glass.
When sound encounters a window, the glass converts some energy into thermal and kinetic energy (resonate vibrations), allows some sound to pass through, and reflects the rest back.
Glass only “absorbs” sound near its resonant frequency (and subsequent harmonics). The resonant frequency of glass is dependent on many factors, including density, thickness and panel size. As is the case with many “hard” building materials, the absorbed sound accounts for only a small fraction of sound energy’s interaction; most sound is either reflected or transmitted through the glass. Sound reflection and sound transmission are two separate acoustic issues with separate solutions.
Sound Reflection – Reflected acoustic energy from an internal sound source can cause a number of issues for occupants. Large, uninterrupted spans of hard materials like glass and gypsum cause specular reflections (echoes) and contribute to excessive reverberation and noise levels. These conditions can contribute to a poor acoustic environment in which speech is difficult to understand and music clarity suffers.
Specular reflections are compounded when there are other hard surfaces in the room. Flutter echo, heard as “ringing”, happens when sound bounces back-and-forth between parallel reflective surfaces (between walls or floor-to-ceiling). Flutter echoes greatly degrade speech intelligibility and music definition. This is a big problem in studios, offices, conference rooms and theater/media rooms. If there is an abundance of reflective surfaces, background “noise” from latent energy will cover up or distort the direct sound.
Typically, these issues are corrected with sound absorbing materials. However, we cannot simply “resurface” the glass with sound absorption, like we would with concrete or gypsum, without impacting transparency. Until someone invents invisible acoustic foam or fiberglass, sound reflections off glass will continue to be a challenge that needs accounted for.
Sound absorptive materials like thick curtains or acoustic shades provide adequate sound absorption and coverage flexibility. Other creative solutions include “stand alone” furnishings like tall, leafy plants or translucent perforated plastic sheets mounted over top the window. Essentially, any irregular surface you can introduce in front of the glass will help diffuse sound and break up harmful wall-to-wall reflections.
Sound Transmission – More than 90% of all exterior noise comes in through doors and windows. This can be partially attributed to poor weather stripping. “Leaky” windows will not only cause uncomfortable drafts, but allow sound to more easily work its way into our homes and businesses. Sound is a little like water; it will “pour out” through any gaps in the building assembly. Improving sound-loss across glass often starts with replacing the weather stripping and properly sealing any joints with non-hardening acoustic caulk.
Air-tight, limp, massive materials are the best at blocking sound. Glass is rigid, and its heft is limited by transparency requirements that keep it thin. Glass transmits a lot of sound energy, particularly at low frequencies. Laminated glass and insulated glazing assemblies both reduce sound transmission through glass by reducing resonance and adding air-space.
Including an acoustic consultant early in the design process will allow architects and owners to make well-informed decisions. An acoustical consultant will best identify potential pitfalls of using glass and recommend glazing systems and construction techniques to minimize future headaches. This measured approach will result in more beautiful looking (and sounding) spaces!
The current crisis has forced a large portion of the workforce to operate out of their homes. Daily Zoom and Skype meetings have become a ubiquitous part of our lives. For many of us, this shift is only temporary. However, some companies are seeing the benefits of working at home, and are making plans to move employees to permanent remote positions.
I’m sure all of you have been on a conference call in which a team member’s audio is difficult to understand. This could be caused by a microphone or connection issue, but a large number of intelligibility problems are rooted in a room’s acoustics. Let’s take a look at some common acoustic issues in home offices and how they relate to conference call clarity.
Background Noise – Obviously, it’s difficult to understand speech when there is a lot of background noise. It is vital that you isolate yourself from extraneous sound sources as best you can. Some sources (TV, HVAC) are easier to control than others (traffic noise, pets, children etc.). Make sure your office is “closed off” from intruding noise. Remember, sound is a little like water; it will “pour in” through any openings, such as gaps around doors. If possible, install full perimeter seals and door sweeps to improve sound isolation in your office. If you have sound transmitting through a wall, ceiling or floor, you can consider adding a layer of mass loaded vinyl to the assembly in order to help block unwanted air-borne noise. You can then cover the mass loaded vinyl with SoundChannels® like in this blog.
Reverberation – In simple terms, reverberation is the sound energy that remains in a listening environment as a result of lingering reflections. The reverberation time (RT or RT60) quantifies how quickly an impulse sound decays in a space. Reverberation time is dependent upon the volume and surface materials of a given room. Large spaces with hard materials (tile, drywall etc.) have longer reverberation times, while small rooms furnished with “softer” materials (carpet, drapes etc.) sound more much more “dead”. Speaker phone conversations require a very short reverb time, for optimal clarity, somewhere in the .5s range (half of a second). You can reduce reverberation in your home office with the addition of “fluffy” or irregular furnishings, acoustic panels, rugs, curtains and plants.
Flutter Echoes – Flutter echo, which can be heard as an annoying “ringing sound”, is caused by parallel reflective surfaces. In certain critical listing environments, sound diffusers are used to alleviate flutter echo. Flutter echoes can greatly degrade conference call clarity. This phenomenon can occur between two walls or floor-to-ceiling. To control flutter echoes in your office, you should break up any parallel surfaces with furnishings and/or sound absorptive treatment.
Reach out to Acoustics First® for a treatment recommendation for your home office!
Here are a few new pics, courtesy of one of our longtime associates in New York. For this facility, they installed several arrays of our Sonora Ceiling Clouds, some of them in custom trapezoidal shapes! Sonora Ceiling clouds are often a great option in facilities with high ceilings, but limited wall space.
From time to time, we have folks who require a good dose of sound absorption for their space, but desire a less intrusive look than that of ‘standard’ acoustical panels. For situations like this our Tone Tiles® are often the perfect solution. Although these panels are paintable and printable, when left in their ‘unfinished’ state they have a soft white color which is very subtle and tends to blend in well with many different environments. Here are a couple of pics from a recent ceiling installation.
As you can see, the panels almost disappear into the ceiling!