Liza Cruze would love to put a plaster ceiling in Salt of the Earth, the Garfield restaurant that she, her husband Doug and chef Kevin Sousa hope to open next month.
"Visually, that's exactly what I would want in there, but we can't do it because I know it's going to be too loud," she said.
The guerrilla dinners that Mr. Sousa held in the industrial Penn Avenue space last summer have helped guide the Cruzes, both architects, as they finish designing the restaurant.
"It was unbelievably loud," Ms. Cruze said. "What those trial dinners showed us was that the space was all hard surfaces."
Restaurants that are too noisy are a common customer complaint. Especially in a city with an older population, diners often express frustration with restaurants where they love the food, but can't hear their companions.
Restaurants should be prepared for more of these complaints, as the rise in the use of portable music players and headphones has made noise-induced hearing loss more and more common.
Unfortunately, while the dining population has been getting slightly deafer, the noise level in restaurants has only increased, due to both design trends and cultural shifts around the definition of fine dining.
Bill Kolano of Kolano Design is working on Donato's, an Italian restaurant that will open this summer on Freeport Road in O'Hara. He compared the way sound waves behave to ping-pong balls. "If you throw a handful of ping-pong balls at a hard flat wall in front of you, they will all bounce back toward you. If you take the same handful of balls and throw them at a wall of carved mouldings or velvet drapes, the balls will bounce in different directions or die."
Designers can use soft materials to absorb sound, but they can also make use of other aspects of design. "Rooms rich with carvings, mouldings, sculptural furniture, rippling draperies and textured carpeting are acoustically comfortable," Mr. Kolano explained, "because the sound waves break up when hitting the complex surfaces."
The modernist design that has become so popular in restaurants is typically full of hard, smooth surfaces and lots of wood, metal and glass. It is visually appealing, but can be acoustically disastrous.
Meanwhile, as food has become the central aspect of the restaurant dining experience, chefs have felt empowered to strip away some of the details of traditional fine dining, such as white tablecloths, lots of space between tables and heavy curtains concealing dining rooms from view.
That means that designers must be creative in their use of materials to balance the visual and acoustic demands of the space.
"We're choosing products that hopefully will be nice looking, but their primary purpose is to deal with acoustics," said Ms. Cruze, about the Garfield restaurant. Noise reduction strategies include an acoustical tile ceiling designed to stop the reverberation of sound and fabric-covered insulation panels around the mezzanine.
But restaurateurs shouldn't just think of noise as something they want to mitigate. The sound levels and other design elements affect how diners behave in the space.
"The higher the sound [level], the faster you eat," said Mr. Kolano, who also listed bright lighting, loud colors and less-comfortable furniture as design components that make people eat up and get out.
Some restaurants use these tactics on purpose, but other restaurants may not realize the message that their environment is sending diners.
Many restaurants seem to think that once they've said "yes" to music in the dining room, the decision-making process is over. At Salt of the Earth, Alberto Vazquez, a friend of Mr. Sousa's, is helping determine what type of speakers to buy and where they should be placed.
At Big Burrito restaurants, such as Eleven Contemporary Kitchen in the Strip District, Casbah in Shadyside and the Mad Mex chain, there is an ongoing conversation about what kind of music should be played, said Bill Fuller, corporate executive. Music is a great way to give a space personality, but a poor choice can quickly alienate guests.
Restaurants should also train servers to be sensitive to concerns about noise. Figure out which tables are quieter, and try to accommodate people who request them. And if too many people complain about the noise, make improvements.
Ms. Cruze certainly hopes that they've adequately addressed the noise issues at Salt of the Earth, but she acknowledged, "We have a couple of spots in our back pocket where we can put some more soft materials if we need to."