By Tyler Adams, Mei Wu Acoustics[dropcap]T[/dropcap]he aural experience of dining is just as important as the visual, olfactory, or gustatory. Poor acoustics can negatively affect the dining experience and dissuade repeat business, even if the food is top-notch. This is underscored by the business-reviewing website Yelp, which allows users to rank an establishment’s perceived “noise level” as part of their review.
The prevalence of noisy restaurants can be traced to recent aesthetic trends that favor materials that are acoustically very reflective—metal, wood, exposed concrete, glass, stone, and tile. These materials are desirable from a practical standpoint because they are easy to clean and maintain. Many sound-absorbing materials tend to be porous and soft, such as thick carpet, heavy drapery, upholstered furniture, fabric-wrapped fiberglass panels, and foam. Such materials can pose hygienic and maintenance challenges when located in areas prone to dirt, spills, splatters, and sprays. (In kitchens and food preparation areas, for example, porous materials are typically prohibited by health codes. Thankfully, there are sound-absorbing materials and ceiling tiles that are nonporous, cleanable, and suitable for use in food prep areas.)
In our daily life, the sounds we perceive consist of the direct sound from a source (a person talking, a chair scraping, a car honking, etc.) as well as sound reflections from the many surfaces in our environment. These sound reflections are often described as reverberations. Imagine the sound of a handclap in a gothic cathedral—the clap itself is very brief but in this highly reverberant space, reflections cause the sound to linger for many seconds.
Reverberant reflections will add to the total level of sound within a space. In noisy reverberant environments, people will tend to raise their voices in order to be understood—termed the Lombard effect—and this in turn will cause the sound levels to rise even higher. Sound-absorbing materials are used to reduce reverberant reflections and thereby reduce the overall sound levels within a space.
Reducing the reverberant reflections is desirable for a number of other reasons: reflections can obscure our ability to hear sounds clearly and understand speech, make it difficult to locate where sounds are coming from, and make music sound muddy. On the other hand, if sound-absorbing materials are overused and too many reflections are eliminated, a space can feel eerily dry, quiet, or dead. A delicate balance must be achieved.
As with any design discipline, there is no one-size-fits-all acoustical solution that can be applied to every restaurant. A steakhouse or country club may demand a quiet or hushed environment where people talk in relaxed voices, with the clink of silverware subtly audible in the distance. An urban coffee shop may demand a lively atmosphere with the din of conversation blanketing the frequent whir of the espresso machine. A sports bar may have amplified sportscasts, where it is important to clearly understand the broadcast yet still be able to conduct a conversation. For each of these spaces, we have expectations of what they should sound like, and the acoustic environment can help reinforce or establish a sense of place, identity, or character.
As with any architectural project, the desires and expectations of the owners and their patrons can guide a variety of design goals. Some of these design considerations may include the following: How well can patrons hear each other at the same table? Will patrons need to raise their voices in order to be understood? Will conversation at one table be overheard by or disturbing to an adjacent table? How loud will the restaurant be at full occupancy? Will the restaurant have amplified music or speech that needs to be clearly understood by the patrons? Is the business in a mixed-use building and adjacent to residential spaces? Would elevated noise levels affect nearby residents? Do the recommended acoustical finishes meet the aesthetic, financial, and maintenance requirements of the project?
Other factors that can influence the noise levels within a restaurant include the number or density of patrons, the level of background music (if any), noise transmitted from the kitchen, kitchen equipment exposed to the dining area, and the level of noise generated by the HVAC system.
Sound-absorbing materials are the primary means for controlling the buildup of reverberant noise in restaurants. There are a variety of material options and aesthetic possibilities. Materials can be strategically hidden from view or integrated seamlessly with the material palette of the space. Alternately, sound-absorbing materials can be featured prominently and serve as part of the décor—as colorful patterns, visual designs, or sculptural elements. With further awareness of the acoustical issues in restaurants and a little creativity, ingenuity, and engineering, unbearably noisy restaurants can become an exception rather than the rule.
Tyler Adams is a senior acoustical consultant at Mei Wu Acoustics, a firm specializing in noise, vibration, and acoustical engineering, with offices in the San Francisco Bay Area and Los Angeles. Tyler holds a master’s degree in architectural acoustics, was the recipient of a Fulbright scholarship in 2012, and is the author of the 2016 book Sound Materials: A Compendium of Sound Absorbing Materials for Architecture and Design by FRAME Publishers.
This article will also appear in The VIEW, the quarterly publication jointly curated by the three Bay Area chapters of Commercial Real Estate Women (CREW)—CREW San Francisco, CREW East Bay, and CREW Silicon Valley. CREW is a nationwide business networking organization dedicated to the advancement of women in commercial real estate. For chapter news, events, and membership information, visit the Bay Area member organization websites at crewsf.org, creweastbay.org, and crewsv.org.