When in Rome30 April 2010
What do you do when you have a restaurant with a fabulous location and chef but with terrible acoustics? The food may be great but the irritating sound will chase away many of the guests. This was the problem facing the Tatá Restaurant in Rome.
After talking to his architect, the owner Sergio appointed an acoustic engineer to assess the problem. Having seen the solutions offered at the Palazzo delle Esposizioni in central Rome, they called in Pellisari Consultancy, the
consultancy arm of NACSound Srl.
Francesco Pellisari has worked in acoustics and design for many years. He explained that unwanted resonance was a cause of many of the acoustic problems and agreed on a plan of action, outlined over the following pages.
The hard reflective original marble surface was replaced by specially designed 30mm thick flooring made of many pieces of compressed wood. Each piece is formed with a small air gap that runs along the edge of the surface. This is filled with an acoustically opaque wax and is excellent for absorbing high frequency sound.
The original plaster covering was very reflective of all wavelengths. This was covered with 30mm of acoustic plaster. This material starts life as a mixture of plaster and polystyrene, which is then chemically removed, leaving an air-filled product that is strong and light with an exceptional ability to absorb medium and high frequencies.
To reduce the resonance of the low frequency wave, special pieces of wood were hung from the walls. These banner-like structures are filled with air and work like a reverse drum skin, absorbing the low deep booms, so that the entire wall increases its sound absorption. They are attached to the wall by hinges so that they can be angled to create the optimum effect.
Wine rack corner
The junction of hard glass windows and walls caused particular problems in one corner, so an ingenious solution was employed. On this wall was mounted a floor-to-ceiling wine rack. To break up the resonant waves the cubicles were made to different sizes and the wooden sides and shelves were of different depths.
A false ceiling was fitted, made of MDF. To improve its high frequency absorption, perforated slits were cut through to a central hollow space behind in which was placed 100mm Hollowfill.
The restaurant has a very high ceiling and the voices of the guests resonate harshly. To overcome this and to effectively lower the ceiling, large rectangular pieces of ‘kite’, a paper-like material, were suspended from the ceiling. These absorb most frequencies and cut the wavelengths, thereby reducing any harshness and disturbance. Also, by lowering the ceiling the perceived space is more welcoming and intimate.
The central part of the restaurant is small and square with one metal covered wall. It produced a very large resonance at a precise frequency. The frequency was calculated and long, thin light boxes were positioned above the bar to disrupt the wave.
To supply the entire restaurant and the bar zones with stereo sound at a low, yet audible level, two Kayak speakers were chosen. These aluminium omnidirectional stereo speakers were suspended from the ceiling with the computer-designed acoustic wave-guide at head height. This diffused the sound in all directions and delivers complete sound saturation of large spaces.
To enable the restaurant to host loud party-type events, seven ceramic Zemi speakers were installed: two in the bar zone and five in the restaurant. These multidirectional speakers were suspended three metres from the floor so they concentrate the sound beneath them and limit excess noise disturbing the surroundings.