Restaurant Acoustics

The basic concept in developing a good sounding restaurant is a sense of privacy. It’s the feeling that one’s conversation is not being overheard by others nearby. How people know they have privacy is because they can’t exactly eavesdrop on the conversations around them. In order for people to have privacy they want to talk quietly and be heard clearly, just above the hubbub. By the time their voice travels out across other tables, it is lost in the hubbub. But speaking quietly and being heard is not exactly easy when the room is filled with hubbub. Here is where the low ceiling comes into play. The ceiling is shiny and reflects the vertical part of a table top conversation right back town to the table where it belongs, and then back up again, and then back down again. To have a quiet table top conversation we need a reflective ceiling.

In order to have privacy in a restaurant the intrusion of sound from afar must be blocked. Something has to be done to attenuate loud sounds from across the room. If we hear the neighboring table speaking up, we can also see the animated movements out of the corners of our eyes and expect to hear the sounds. But hearing equally loud sounds from somewhere across the room is annoying. We have no visual clue about that sound being made and so it becomes an intruding sound. Horizontal sound needs to be attenuated in a good sounding restaurant.

Table top conversations

It is a fundamental social event, eating and visiting at the same time. A good restaurant promotes table top conversation by insuring that people can visit with each other across the table, without a strained effort or raised voice. In addition to the direct sound between people at the table, the reflection of sound off the top of the table makes people’s voices louder, without having to raise the voice. A good reflection off the ceiling of the restaurant also contributes to a bright and clear table top conversation.

The acoustic coffered ceiling system uniformly distributes large sections of highly reflective ceiling surfaces, separated by narrow strips of sound absorbing panels, otherwise known as acoustic beams. These ceiling vertical ceiling bounces are essential for clear table top conversations. This is one important reason that this system works best on lower instead of higher ceilings.

Acoustic Coffered Ceiling

In good restaurant acoustics we want to reinforce table top conversations, allow for vertical reverberation and attenuate intruding sounds from across the room.   The ASC acoustic beam coffered ceiling system does just that in lower ceiling rooms.

A little hubbub  is a good thing… and just the thought of adding sound panels to a restaurant brings chills to the owner, imagining how awful a quiet restaurant sounds. Hubbub provides a sense of welcome to the newcomers and privacy to the seated guests.  Hubbub encourages table top conversation and good fun.  When we work to re-voice a restaurant, we sort out what is working from what is not working.

Most restaurants that have a noise problem are not on the drawing board but are up and running. Starting over, to redesign and remodel the restaurant to sound better is not an option.  There is a cost effective “magic bullet” that tends to work very well in most restaurant spaces that need the help.  It is the ASC Acoustic Beam Coffered Ceiling System.  It promotes the needed background ambience effect of hubbub.  It cuts down on the intrusive sounds from across the room and it supports crystal clear table top conversations.  And here is how it works.

The Acoustic Coffered Ceiling is a directional acoustic ceiling mounted grid.  It is officially a ceiling mounted acoustic baffle.  However it is disguised as a classic architectural element, the coffered or box beam ceiling.  It allows vertical sound to be reflected and horizontal sound to be absorbed.  It works exactly opposite of standard T-bar acoustical ceiling which absorbs vertical sound and reflects horizontal sounds.

The system works best in wide and or long rooms with fairly low ceilings, 8 to 12 feet.  The height of higher ceiling rooms minimizes the ability of the acoustic coffered system to independently control vertical and horizontal sound and the ceiling system becomes an attractive general purpose noise control ceiling, making acoustic adjustments only in the reverb time.  The lower the ceiling and wider the space the more powerful and vivid becomes the performance of the acoustic coffered beam ceiling.

The Acoustic Coffered Ceiling typically will have 3 to 5 foot squares of existing ceiling separated by 6” wide and 2” deep sound absorbing faux beams.  Different depths or widths of acoustic beams produce more or less aggressive results in either the vertical or horizontal direction, as does changing the size of the grid pattern.  These faux beams are light weight, fire rated and install easily with nothing more than a few dabs of acoustic ceiling adhesive.   They are beveled and shaped to form any number of patterns, the most common of which is the mitered grid pattern.

The size of the exposed ceiling in the grid determines how bright the table top conversation will be.  The larger the ceiling grid, the lower is the vertical absorption coefficient.  A 4×4 grid with a 6” beam provides a vertical NRC of about 25%.  (Noise Reduction Coefficient).  Unlike an acoustic tile, that provides the same NRC, this system alternates small areas of 100% absorption with larger areas of 100% reflection.  This is very unlike typical acoustic T-bar ceilings, where the absorption and reflection is uniformly distributed.  With the acoustic coffered ceiling, the ceiling reflection is not dull as with T-bar ceilings, it sparkles.

Sound traveling in a horizontal direction, grazing the ceiling runs into the sound absorbing sides of the acoustic coffered ceiling.  The depth of the acoustic coffered beams determines how aggressive it is with respect to absorbing the grazing horizontal or “cross talk” type of sound out of the restaurant air.

The reflective ceiling not only returns the table top conversation back down to the table top, which makes it more easily heard, but it supports the buildup of the background noise floor, the very important hubbub effect.  Because the ceiling is composed of large squares of reflective surfaces, and despite their being separated by sound absorbing edges, multiple vertical reflections are accommodated.

When people are talking in a space that has an acoustic coffered beam ceiling they hear the table top conversation clearly, enjoy the sound masking or privacy effect of ongoing hubbub and are protected from loud and intruding sounds from across the room.