Two Acoustic Solutions for Today's Multi-Use Halls

The multi-use hall emerged in cities around America during the 1950s and 1960s as a logical outgrowth of the grand but artistically unsuccessful municipal auditoriums of the 1920s and 1930s. The municipal auditorium in American cities was the inevitable result of pressures from the artistic community's need for a larger, grander performance facility and the need to further the artistic development of the local symphony, opera, and theatre companies. It also served as the convention hall, grand ballroom, and ceremonial space for downtown.

After World War II, there was a feeling among designers and politicians that modern halls should take on a more egalitarian and democratic form, and thus eliminate the exclusive boxes and grand tiers that created barriers between audiences. As part of this post-war civic expansion and civic pride, democratic buildings were designed as homes for the city's symphonies, theatre troupes, and community concerts, as well as expanded convention meeting spaces. In the 50s and 60s, cities such as Austin, Charleston, Memphis, and Dayton built what were then considered state-of-the-art facilities. At the time they were designed, these single-balcony, wide, fan-shaped halls were considered state of the art technically, acoustically, and artistically. Acoustically, these halls lacked sonic impact and intimacy for theatre, provided limited presence or clarity for opera, and were devoid of the warm, rich reverberation for the symphony.

A new breed of multi-use halls, which offered vast improvement both visually and theatrically over these civic auditoriums, was built in the 70s and 80s. Often they were little better acoustically than the buildings they replaced; they were technologically unsophisticated, often using a number of massive, moving ceilings that closed off the hall volume in order to create adjustable acoustic environments to meet the range in reverberation time needed. These multi-ton, counterweighted, steel contrivances were at times unsafe and in the end provided only a gross level of acoustics tunability and variability. No wonder the multi-use hall got a black eye within the musical community.

In the 1990s, our firm, Jaffe Holden Acoustics, set about to solve the conundrum of providing acoustic excellence for symphonic performances while meeting the theatrical and acoustic needs of opera, ballet, musical theatre, and amplified performances. We actually developed two new design directions based on the needs of the facility, users, and budgets. One uses a sophisticated orchestra shell called the “Concert Hall Shaper,” the other an innovative system of double pit lifts to bring the orchestra almost fully into the hall, where the auditorium can function as a one-room concert hall.

Thelma Gaylord Theatre
The new Thelma Gaylord Theatre in the Oklahoma City Civic Center serves as the home to the Oklahoma City Philharmonic, the Canterbury Choral Society, and Ballet Oklahoma, as well as host to touring Broadway and popular productions. But with such a truly multipurpose venue, how does one create an acoustic setting suitable for all performances? The answer was to create a high-tech, flexible stage that has the ability to change its shape, and an audience chamber that can change its response to sound.

To that end, Jaffe Holden Acoustics designed the Concert Hall Shaper. The Shaper consists of a ceiling that stretches from wall to wall, just above the proscenium opening, actually sealing off the stage from the upper stage house. When the ceiling is dropped into place from its storage position on the rear wall of the stage, it creates a closed chamber of approximately 250,000 cu. ft. around the orchestra.

Another component of this design is the acoustical reflectors that extend over the orchestra toward the audience, which both project and direct sound out to the audience and reflect sound across the stage to enhance onstage hearing, communication, and intonation.

Conventional-looking acoustical wood rolling shell towers are positioned around the performers to further reflect, blend, and balance sound and can be located in three configurations: chamber music shell for 40 to 60 musicians; full symphonic shell; and finally, the maximum depth to flatter a 90-piece orchestra and chorus.

The orchestra pit lift in front of the stage is raised to extend the performance floor 12' toward the audience, creating a greater sense of intimacy between performers and audience, and positioning the string section closer to the audience and hall reflecting surfaces, such as side walls and forestage reflector. All the Concert Hall Shaper elements can be stored out of the flyloft and rigging, totally clear of the linesets for the next show in less than one hour.

To meet the needs of the amplified productions, adjustable acoustic elements are also located within the audience chamber. These elements are in the form of moveable, heavy velour, 100% full curtains located on the upper and lower side walls, designed to adjust the amount of reverberation time and reflected energy in the room. When the drapes are exposed, along with the storing of the Shaper, they transform the very “live, resonant, and warm” hall that is ideal for symphonic performances, into a more “dry” environment, which is more suited for amplified productions.

When the hall was ready for opening, consultants from Jaffe Holden tuned the hall to optimize the settings for each type of performance. For symphonic music, the Concert Hall Shaper shell ceiling reflectors and the forestage reflectors were adjusted during the orchestra's rehearsals and initial performances. By raising and lowering the reflectors and adjusting their angles, the acousticians balanced the orchestra sections to optimize onstage hearing and communication, as well as control the amount of energy being projected out into the audience, providing the optimum acoustic environment for symphonic productions.

Bill Heard Theatre
The 2,000-seat Bill Heard Theatre at the River Center for the Performing Arts in Columbus, GA, was designed to meet both stringent budget requirements and the acoustic goals of a true multiple-use hall: the ability to flatter symphonic events, opera, ballet, and Broadway productions, as well as amplified performances by country music stars, such as Travis Tritt.

As an alternative to the Concert Hall Shaper, where the symphony perhaps draws a smaller audience and the cost is an issue, our firm wanted to create a new, compact orchestra shell and position the symphony out into the hall, occupying what would be the first eight rows of seats. Two lifts raise the floor to stage level, positioning ⅔ of the orchestra 30' out into the hall.

The advantages of this are many. First, the stage proscenium must be closed off so that sound is not lost in the theatrical drapes or flyloft. Orchestra shell towers are used to either completely close off the opening, or perhaps create an area for the chorus, if one is performing with the symphony. With the stage opening closed off, the hall is acoustically a one-room concert hall — the ideal symphonic environment, because the symphony and listeners are in the same space, not separated by the proscenium opening.

Other advantages: Research shows that 1,600- to 1,800-seat halls are acoustically more successful for symphonic music; there is more air volume per seat in the hall as seating is reduced. This enhances reverberation time, richness, and reverberation.

One result of locating the orchestra on the lifts is that the source location of musicians can vary over a large area — from the proscenium to 30' out into the hall. This causes unusual challenges for wall shaping and ceiling shaping that must provide optimal acoustic response with very limited resources. Shaping the side walls in sweeping convex curves spreads and blends sound from the orchestra to maximize presence and clarity (early sound) while blending and mixing warmth and reverberation (late sound).

In addition to two stage elevators and a 25-ton forestage canopy, there is another adjustable acoustic system primarily for use by amplified concerts, lectures, and conferences, etc. Motorized thick velour drapes extend from pockets hidden in the side walls and cover large expanses of walls under the balcony, upper side wall areas, and in the large acoustic volume. These drapes serve to dampen and control reverberation and liveness for these productions by reducing reverberation time and hall responsiveness.

The conundrum of providing acoustic excellence for symphonic performances while meeting the theatrical and acoustic needs of opera, ballet, musical theatre, and amplified performances has been solved in two ways. The Oklahoma Civic Center uses a sophisticated orchestra shell called the Concert Hall Shaper; the River Center a clever system of double pit lifts to bring the orchestra almost fully out into the hall.