Classical Made New - Schermerhorn Hall Builds on Nashville's Civic Legacy
January 2, 2008
Schermerhorn Symphony Center-the new, 197,000- square-foot home of the Nashville Symphony-occupies a full block of the city's downtown, forming a boisterous yet elegant bridge between the famous replica of the Athenian Parthenon, in nearby Centennial Park, and the Art Deco lines of the Frist Center for the Visual Arts at the other end of Broadway. The neoclassical exterior is sheathed in Indiana limestone, burled to catch the sun's dazzle; yet the front walls have plenty of glass, a modern touch. Evoking the vitreous curtains of other classically inspired recent designs (such as Norman Foster's Hong Kong & Shanghai Bank building), these oversized windows "allow what goes on in the building to become decoration for the city, and vice versa," explains principal architect David Schwarz, of David M. Schwarz/Architectural Services, in Washington, D.C.Inside, the structure is a dense honeycomb of spaces: a lecture hall, a music library, the symphony's offices, various dressing rooms, the concertmeister's suite, four lobbies, a series of reception rooms, a catering kitchen, and "many, many bathrooms," in Schwarz's words. But the heart of the Schermerhorn—which is named for the late maestro and musical director of the Nashville Symphony, Kenneth Schermerhorn—is the Laura Turner Concert Hall, a 30,000-square-foot shoebox design with nearly 2,000 seats, a stage that can hold up to 115 musicians, and a choral loft behind the stage.
The seed of the Schermerhorn's design was planted during a whirlwind tour of classic concert halls. Schwarz and Paul Scarbrough of Norwalk, Conn.'s Akustiks, the principal acoustical designer of the Schermerhorn, joined by other members of the design team, visited halls in six cities: Vienna, Berlin, Amsterdam, Barcelona, Zurich, and Boston. They listened to a concert—sometimes multiple concerts—in each of them and started to get ideas for the Nashville project. So from Vienna's Musikvereinssaal, they borrowed the hall's rich reverberance and its use of natural light; from Berlin's Konzerthaus and from Vienna's Konzerthaus, the gracious series of public spaces around the halls; and from Boston Symphony Hall, the use of two side tiers to promote good balance between reverberance and sonic clarity.
Another decision influenced by European precedents was to illuminate the new hall with natural light. "We were in Vienna, listening to the closing chords of a Dvorak requiem fade just as the last rays of sun of the day filled the room with this incredible golden glow," Scarbrough recalls. Under the hall's coffered ceiling, soundproof clerestory windows—30 in all—run along the two long walls.
According to Schwarz, the key to creating a workable music space is collaboration between architect and acoustician, with the rapport between himself and Scarbrough being a perfect example. "Paul will tell us how a surface needs to perform, and we'll design it to do that and also make it look good aesthetically," he says. He cites the cornice beneath the windows, which serves to deflect sonic energy downward, and the columns on the side walls, which act as high-frequency diffusers.
Schwarz, who also designed Bass Hall in Fort Worth, Texas, and Severance Hall in Cleveland, points out that this kind of collaboration can significantly affect the bottom line. Of the Schermerhorn's total $120 million cost, $90 million was spent on hard construction costs, while $30 million went to overhead. Schwarz contrasts that with the Renée and Henry Segerstrom Concert Hall in southern California, which cost $200 million. "The difference is attributable to having the interior materials and design work for the music, not as an aesthetic on its own," he says. "The reason the classic European music halls sounded so good was that the sounds worked with the architecture. The room is one of the instruments."
Acoustics
Acoustical design is always a tug-of-war between dynamic reverberance and control of the sonic reflections that create that reverberation. Sound is energy, striated into various frequencies. Its behavior can be reasonably predicted according to Newtonian physics, although an almost exponential number of variables—such as materials and air density—make acoustics as much an art as a science.
Sound energy emanates from a source (in this case, the stage) and will undergo two fundamental transformations as it encounters resistance. When the energy hits hard surfaces, such as walls, it will reflect back into the hall. The directionality of those reflections will depend mainly on the angles and density ("reflectivity") of the surfaces.
The other phenomenon is diffusion: When sonic energy intersects with nonreflective surfaces, such as curtains or even people, some of that energy is absorbed by those materials. The careful choice of these materials is one way that absorption is used to control additional reflections inside the hall. For instance, at the Schermerhorn, columns along the side walls act as high-frequency diffusers. One less-obvious but inspired means of controlling diffusion in the Schermerhorn is a rule that winter concertgoers must put coats in the cloakroom: If the hall were full of coats folded over arms or seats, this would significantly—and unpredictably—increase the absorption of high-frequency sounds.
The Schermerhorn was meant to be a dynamic hall, and its materials underscore that. The walls are hard plaster on concrete; the flooring is of the hardest woods, such as Brazilian cherry, African makore, and the hickory native to Middle Tennessee. Even the nickel-silver finishings were designed to enhance the hall's reverberant quality, which Scarbrough's CAD-based measurements place at 1.96 seconds (the time it takes for a transient sound to return to its origination point after bouncing off the rear wall) in the middle frequencies—between the 1.85 seconds of the Boston Symphony Hall and the 2.1 seconds of Vienna's Musikvereinssaal, two of the rooms that served as acoustical templates for the Schermerhorn.
This lively reverberance, though, is tamed by technology. Along each side of the room, fabric-covered fiberglass panels sit on tracks in thin silos under the floor and can be raised to absorb sound reflections. Also, on the side balconies and on the clerestory level, several heavy (32 ounce weight per yard) draperies are stored in curtain pockets. All of these acoustical tools are automated, and eventually their controller will have single-button configurations for various types of performances.
The Schermerhorn uses technology not just to enhance the acoustics inside, but to block noise from outside. The hall is a building-within-a- building, with a two-inch acoustical gap running between the inner and outer shells. All noise-generating systems, such as the HVAC, rest on absorptive neoprene-puck foundations in the basement, where the ground mass also helps stabilize them; in some cases (such as ductwork and pipes), they are also supported by ceiling hangers. When potentially disruptive noise has an unavoidable track into the shoebox—such as through the HVAC system—it encounters ducting that is lagged on the outside with two layers of gypsum board and has fiberglass lining.
Convertibility
One of the Schermerhorn's most radical design features is its convertible floor space. The audience seats are arrayed on eight massive "chair wagons"—movable platforms that are roughly 60 feet wide by 15 feet deep. (The most famous chair wagon in the country is the bandwagon at Radio City Music Hall, installed in 1933, which still moves the orchestra forward during Rockettes performances.) Each of the Schermerhorn chair wagons, independently powered by small electric motors, rolls—guided by side rails—from its place on the floor toward the front of the house.
Just in front of the stage, where the lowest-raked of the chair wagons will sit, the floor is actually an elevator whose area is just slightly larger than that of a chair wagon. One by one, the platforms can be lowered, via a spiral lift (a self-extending, screw-type device), to the basement below the audience area. They are then rolled off in reverse order from their rake, revealing a 5,770-square-foot open floor that can be used as a ballroom. And it became just that on Sept. 9, 2006, for the Schermerhorn's formal opening ceremony, when a performance by the symphony gave way to an evening of dancing on the floor. The changeover time was less than an hour.
"This is more than just your typical symphonic concert hall," says architect Randy S. Nale, of architect-of-record Earl Swensson Associates. "This convertible floor makes it a multiuse space, but it never compromises its primary purpose of being the home of a symphony orchestra."
The design of the chair wagons, which was specified by the theaterdesign consultants Fisher Dachs Associates of New York City and fabricated by J.R. Clancy, a stage-rigging manufacturer in Syracuse, N.Y., is as complex as it is clever. The fact that each one weighs more than 30,000 pounds is not an accident. "We needed mass, and lots of it," says Scarbrough. "The purpose was to avoid creating a membrane in the floor of each unit that could resonate in response to the music and suck the low-frequency energy out of the room." Thus, each chair wagon has a heavy tubular metal frame, on top of which are layered a ¼-inch steel plate and hardwood floorboards.
Joe Mobilia, an associate principal at Fisher Dachs, says one major challenge was to move the massive load across the main floor without damaging it. "The chair wagons were moving across a polished floor that had to always look good, and wheels could cause ruts or dents in the floor," he explains. The solution was several rows of 6-inch-wide steel rollers on which the mass of each wagon would be more evenly distributed. Technicians at J.R. Clancy then devised the sprocket-andchain guide system, and they created a scaled mockup of a Schermerhorn chair wagon that was run over a wood surface for several thousand cycles to test for potential damage to the flooring.
The Grand Tour
On their European tour, David Schwarz and Paul Scarbrough visited classic concert halls in five cities: Vienna, Berlin, Amsterdam, Barcelona, and Zurich. Back in the United States, they also dropped in on Boston Symphony Hall. "We listened to a concert in each of them," says project acoustician Scarbrough. "They were in quick enough succession that you could grasp the differences between them, as well as what they had in common that made them such great concert halls."
From each stop, Schwarz and Scarbrough drew inspiration for elements of the Schermerhorn's design:
From Vienna's Musikvereinssaal: The hall's rich reverberance, sonic impact, and ample natural light.
From Amsterdam's Concertgebouw: The permanent choral seating behind the orchestra and the reverberant characteristics.
From Berlin's Konzerthaus and from Vienna's Konzerthaus: The gracious series of public spaces around each hall.
From Zurich's Tonhalle: The dynamic impact of sound in a small hall.
From Barcelona's Palau de la Música Catalana: The incredible natural light and the richness of the visual environment.
From Boston Symphony Hall: The use of two side tiers to promote good balance between reverberance and clarity.
by Dan Daley
