Auditorium Acoustics

Theater—Monroe Community College, Rochester, New York · OAA provided comprehensive consulting services to Popli Group and ME Engineering for this challenging renovation of a multi-purpose 600-seat college theater. This project received the following 2017 awards: Rochester Chapter CSI Annual Outstanding Project, AIA Rochester Merit Award, AIANYS Excelsior Merit Award for Public Architecture, and AIANYS Award of Citation.

600-seat college auditorium

Theater, Monroe Community College, Rochester, New York. Photo credit: Popli Design Group

  • Room Acoustics: The original finishes in the Theater comprised sound-absorbent side and rear walls, resulting in a reverberation time that was too low for music performances. Popli Group designed new visually-stunning wall and ceiling surfaces comprising wood-veneered gypsum board panels, and OAA assisted with custom and unique angles for every panel in the room. The panels provide stiffness for sound reflection and are aimed to provide superb natural reinforcement of sound from the stage. Gaps between panels were deliberately left open to increase the room volume and reverberation time. Operable sound-absorbing banners at the rear of the room tailor the Theater to conditions more suitable for either speech or music programs.
  • Sound Isolating Constructions: The original Theater ceiling was a continuous layer of gypsum board suspended below lightweight roof construction, providing sufficient control of rainfall noise. The new ceiling panels do not provide similar control of rainfall noise, so a special gypsum board “lid” was designed above the finished ceiling system. This “lid” system was challenging to construct effectively, since it is penetrated numerous times by roof structure, ceiling structure, ductwork, piping, etc. In addition to control of rainfall noise, the “lid” provides necessary control of ductwork breakout noise near the rear of the Theater, where ductwork is close to the mechanical room and before air handler noise is attenuated by duct silencers.
  • Sound System: The program called for a sound system providing speech reinforcement and successful support of musical theater. The users requested 24 channels of professional-quality wireless microphone capability, 32 channels of on-stage wired input capability, and a digital mixing system that could control this 0high channel count without the use of input fader layers. These requirements necessitated careful selection of equipment (including re-use of existing analog wireless microphones paired with new digital wireless microphones), as well as careful coordination regarding the space taken by sound system equipment (the installed sound system equipment fills two 65-inch-tall equipment cabinets and uses a mixing console system that weighs 100 pounds and is 64 inches wide). Although the Theater sound system was designed with a central loudspeaker cluster on the proscenium centerline, analysis via 3D acoustical modelling software indicated that the relatively low ceiling in this space also necessitated three mid-house fill loudspeakers in order to provide even coverage to all seats. The opening at the Control Balcony has no glazing and is protected by a roll-down grille, remaining acoustically open at all times.
  • HVAC Noise and Vibration Control: Pre-renovation sound levels in the Theater house ranged from NC-37 to NC-40. All existing ductwork outside the mechanical room was replaced with new, acoustically-lined ductwork, sized for low airflow noise and incorporating silencers. The existing air handler and ductwork within the mechanical room were re-used. Post-renovation, sound levels in the house range from NC-26 to NC-31, providing a significant reduction in sound levels.

Center for the Arts, The College of Staten Island, Staten Island, New York · OAA provided comprehensive consulting services concerning the acoustically critical spaces, including a 900-seat concert hall, 430-seat Williamson Theatre, and 150-seat recital/lecture hall. Recommendations for music rehearsal, cinema, and broadcast facilities were also developed.

Auditorium acoustics

The Recital Hall, ©2001 The CSI Center for the Arts

Acoustical issues included:

  • Protection of performance spaces from aircraft noise caused by Newark International Airport.
  • Planning adjacencies to minimize costly sound isolating constructions between performance, broadcast, and music teaching spaces.
  • Construction recommendations and details to assure effective sound isolation between spaces.
  • Shaping and finishes for optimum performance and teaching space acoustics.
  • HVAC noise and vibration control to achieve low background sound levels, which are critical to good hearing.
Cradle of Aviation Museum and Grumman Omnimax Theater, Mitchell Field, Garden City, NY ·
The museum is an open, multi-story building adjacent to two existing World War I hangars containing exhibition spaces. The new building contains a domed, state-of-the-art OMNIMAX™ motion picture theater. In the OMNIMAX theater, extraordinary sound control is essential for the audience to appreciate and enjoy the wide dynamic range of the theater’s digital sound track. OAA analyzed acoustical features of the proposed air conditioning system to identify noise and vibration control measures needed to ensure quiet.

Omnimax acoustics

Grumman Aviation Museum. © Wiedersum Associates, P.C.

Equally important is that overhead aircraft and nearby street traffic noise not be heard in the theater, especially during the quietest parts of the OMNIMAX program. OAA measured on-site sound levels for 24 hours to quantify the theater’s noise exposure. Wall and roof constructions were identified to provide the optimum degree of isolation.
OAA was selected for the project because of the firm’s familiarity with OMNIMAX theater technology and experience in solving problems in sound isolation and mechanical noise.

Auditorium—Churchville-Chili Senior High School, Rochester, New York · Ostergaard Acoustical Associates provided comprehensive consulting services, assisting architects SEI Design Group, theater consultants Robert Davis, Inc., and mechanical engineers EC4B on the design of this new 1,200 seat high school auditorium.

Auditorium acoustics

Auditorium—Churchville-Chili Senior High School, Rochester, New York

  • Room Acoustics: Sound from speech and music on-stage must be understood clearly by the audience. A 3-dimensional acoustical model of the room was developed to assist in selection of finishes and achieve an appropriate reverberation time. The model was used to adjust the angle of the forward portions of the sidewalls and ceiling planes so as to better direct sound into the seating areas at the rear of the orchestra and the front of the loge. The model was also used to select among multiple options for seating rake and balcony height in order to optimize room acoustics.
  • Concert Shell: Since the auditorium has a tall fly tower and large wings, both of which absorb on-stage sound, a concert shell was designed and specified so music performance sound can be directed into the audience seating and not lost to the fly tower and wings. A Wenger Diva shell was selected, incorporating an aesthetically-pleasing wood finish that matches the characteristics of the rest of the auditorium; full reflector coverage at the stage sides, rear, and top; and air mover technology to efficiently store the shell during theatrical uses.
  • Sound Isolating Constructions: Special constructions are needed to separate the auditorium envelope from the mechanical equipment space as well as music and dance spaces. It is also necessary to keep sound from circulation spaces out of the auditorium. Appropriate partition construction methods were recommended, and all entry points comprise vestibules with two sets of doors.
  • Sound System: A sound system that provides speech reinforcement and successfully supports musical theater is necessary in a large auditorium. In addition, the principal of this school requested a method to simply override most sound system components, allowing sound system usage from a designated microphone input that bypassed the main mixing console. A system was designed that incorporated multiple wired inputs, 16 channels of wireless microphones, a 32-channel mixer, and the requested single-channel override. Output is via four full-range loudspeakers aimed to cover the orchestra, loge, and balcony, a subwoofer, and four stage monitors. The loudspeakers are mounted centrally above the proscenium, just forward of the first catwalk, providing line-of-sight to all audience seating and to the control room mix location under the balcony.
  • HVAC Noise and Vibration Control: Ostergaard Acoustical Associates developed an appropriate background sound level criterion that supports speech intelligibility over the large distances that exist in this auditorium. Preliminary recommendations were provided to the mechanical engineer to achieve the quiet NC-20 criterion. As the design progressed, specific noise control recommendations were made. Due to the use of large ductwork and open-ended ducts instead of traditional diffusers, post-construction measurements confirm that the NC-20 criterion was achieved, and no adjustments to the HVAC system were necessary.
Live Theater—South Orange Performing Arts Center, South Orange, New Jersey
The acoustics are terrific!” — Yo-Yo Ma

. . .fine acoustics. . .” — The Star Ledger

Performing arts center

Live theater ceiling clouds South Orange Performing Arts Center

SOPAC was an acoustically challenging project. In addition to a site adjacent to an elevated New Jersey Transit Railroad, the program called for a large multi-purpose room above the 415-seat live theater, with limited budget. Ostergaard Acoustical Associates provided acoustical consultation to achieve a first rate performance space that meets the needs of the community and Seton Hall University. Our consultation concerned intruding train noise and vibration, room acoustics, sound isolating constructions, and HVAC noise and vibration control.

  • Train Noise and Vibration: Initially we evaluated the potential of audible noise from train vibration passed through the ground. Pre-construction vibration measurements provided the raw data. Our analyses indicated that soil conditions reduced the vibration sufficiently so that radiated noise into the theater would be acceptable. Train noise would seldom be audible, and only at very low levels.
  • Live Theater Room Acoustics: The sound of speech and music performances needs to be clearly and correctly heard by the entire audience. Working with the architects, Rothzeid Kaiserman Thomson & Bee, side wall shape and ceiling clouds were selected and oriented to provide reflections for natural sound reinforcement, diffusion to eliminate harshness, and surfaces that control flutter echo. In addition, other finishes were selected to control echo and temper reverberation.
  • HVAC Noise and Vibration Control: Ostergaard Acoustical Associates collaborated with DVL Engineers to achieve appropriate background sound levels in the live theater. The first step was to establish noise criteria that balanced the conflicting needs for audibility of performances, inaudibility of train passes, and budget constraints. Preliminary noise control recommendations were provided to assist DVL in developing the mechanical design. The initial design was analyzed to determine to what degree the noise criteria would be met, and the noise control features were refined. Following construction, field sound measurements were made and, where necessary, systems were adjusted to meet HVAC sound goals.
  • Sound Isolating Constructions: Special wall constructions and sound isolating doors were recommended to control the penetration of train and street noise, as well as plumbing and other noise sources within the Center.

Cultural Life Center, Roberts Wesleyan College, Rochester, New York · The Cultural Life Center includes the 950-seat Hale Auditorium and the Shewan Recital Hall. These were designed with optimal acoustics in mind to meet the College’s unique needs.

Auditorium acoustics

Cultural Life Center, Roberts Wesleyan College, Rochester, New York

  • Auditorium Serves Diverse Needs
    The college’s 950-seat Hale Auditorium features adjustable components designed to provide the best acoustics for Roberts’ well-known music program, as well as for theatrical programs and events for the spoken word. Ostergaard Acoustical Associates designed the following acoustical features:
  • Classic shoebox shape, selected for the same excellent acoustics exhibited by many of the world’s great concert halls such as Boston’s Symphony Hall.
  • A custom concert enclosure that retracts to expose a theatrical stagehouse.
  • An adjustable canopy forward of the stage with shutters that can open and close.
  • Side wall panels designed to provide lateral reflections that increase the width of the sound image.
  • A loudspeaker cluster that directs sound into the audience areas for clear voice reinforcement.
  • Adjustable rear wall sound absorption for variable reverberation control.
Auditorium acoustics

Robert Shewan recital hall

  • A Recital Hall that Mirrors the AuditoriumThe Robert Shewan recital hall is designed to parallel the auditorium, providing excellent natural acoustics for choral and instrumental classes, rehearsals, and intimate musical performances.  The large 106,000 ft3 volume facilitates balanced sound without  excessive loudness, as well as with appropriate reverberation.  An overhead canopy provides early sound reflections to allow sections of the performing group to better hear each other.  Two exterior walls pitch inward to eliminate flutter echo and reflect sound into the performance/audience areas.
  • HVAC Noise Control: Acoustical aspects of the air handling systems for both halls are engineered by Ostergaard Acoustical Associates to provide low mechanical noise levels so that program sound is not masked. The auditorium is designed for RC-20, and the recital hall is designed for RC-25. To achieve these goals, each element of the air handling system was acoustically modeled to identify required noise control features.
Auditorium acoustics

©2001 Victoria Theatr

Victoria Theatre, Dayton, Ohio · The Theatre, on Dayton’s Main Street, consists of an 1890 Second Empire building, as well as a 1915 auditorium and stagehouse. The interior of the 1890 building and the entire stagehouse were replaced, and the auditorium renovated and restored to create a state-of-the-art 1,200-seat auditorium.
OAA performed an acoustical evaluation of the auditorium prior to renovation. These tests confirmed complaints of poor intelligibility in certain orchestra seats. The problem was traced to delayed sound reflections off of the high ceiling area above the proscenium. OAA specified corrective finishes compatible with this highly visible ornamental plaster area; the finishes controlled the problem reflections and improved intelligibility. OAA also provided finish recommendations to promote an appropriate degree of reverberation, create useful reflections for natural speech reinforcement, and eliminate echo. OAA engineered sound isolation features to control street noise penetration and identified HVAC noise control features to achieve NC-20 levels.

John Harms Center for the Arts, Englewood, New Jersey · The Harms Center occupies a 1926 vaudeville house in downtown Englewood. The $6.6 million renovation included a general refurbishment of finishes in the spirit of 1926, a balcony extension, and the addition of an air conditioning system. The balcony was extended toward the stage to increase capacity by 300 seats, to a total of 1,500. Ostergaard Acoustical Associates analyzed the proposed changes and recommended finishes to promote natural sound reinforcement, while controlling reverberation and echo.
The new air conditioning system allows the center to operate year-round for the first time. OAA established criteria for the system noise levels, provided initial noise control guidelines to the system designers, and analyzed the proposed system to identify noise control measures needed to meet sound level objectives. Methods to control the penetration of street noise were identified.

Additional Auditorium Projects

  • Clifton High School Auditorium
    Clifton, New Jersey
  • Our Lady of Mercy Performing Arts Center
    Rochester, New York
  • Chatham High School Auditorium
    Chatham, New Jersey
  • Donald M. Payne Sr. Technical School Auditorium
    Newark, New Jersey
  • PS-169Q Auditorium
    Queens, New York
  • Chatham Middle School Auditorium
    Chatham, New Jersey
  • West Orange High School Auditorium
    West Orange, New Jersey
  • Indian Hills High School Auditorium
    Oakland, New Jersey
  • Sussex County Community College Theater
    Newton, New Jersey
  • Union High School Auditorium
    Union, New Jersey

Auditorium Acoustics << Architectural Acoustics