The Northshore Performing Arts Center in Bothell, WA, recently opened to much acclaim with actor Ben Vereen performing a tribute to Sammy Davis, Jr. The center is the result of a unique partnership between the Northshore School District, the Northshore Performing Arts Center Foundation, and the City of Bothell.

“It's kind of like a little piece of New York,” says Ed Parker, executive director of the foundation that raised funds for the center and is now the resident presenting organization. “It's a reward for our community.”

When the Northshore School District put up a bond for construction that included a new auditorium, Neil Larson, president of the foundation, saw an opportunity to build the kind of performing arts center that he and his colleagues had been working toward for several years. A voter-approved bond earmarking $6.3 million for the theatre — plus fundraising for the remaining $2.5 million by the Foundation — helped to seal the deal.

Located on the Bothell High School campus, the 25,000sq.ft center has two performance spaces, a 607-seat proscenium theatre and a black box theatre that doubles as a drama classroom. The center is a stark contrast to the school's previous arts venues: a 200-seat theatre and the school gymnasium, where Larson remembers parents crowding outside to hear their children perform at band concerts. At the new center, everyone has a seat, and students now share the stage with artists like Grammy Award-winning George Winston, the Dublin City Dancers, or the cast of Ain't Misbehavin'.

A recording studio and green room afford a real-world theatre experience for students, while the full fly tower and catwalk lighting systems help them learn the technical aspects of show production. School officials hope that this first-class facility will help stimulate the education process.

With visual and performance art that ranges from drama and dance to lectures and music of all genres, a challenge going into the project was providing optimal sound for all of these scenarios. In designing a multipurpose facility, the range of space that works for both speech and music is very narrow. Achieving this delicate balance, while also trying to minimize the noise and vibration from mechanical systems, is a little like walking a tightrope.

Speak Easy

A main goal on this project was to provide excellent speech intelligibility for lectures and drama performances. A monaural theatre sound reinforcement system with a single loudspeaker cluster is suspended above the center of the stage opening. There is infrastructure to support installation of stereo speaker systems with subwoofers in the future.

The center speaker cluster utilizes active speakers (Renkus-Heinz PN12/6-2(T)) with signal processors and power amplifiers that are installed within the speaker cabinets. The processors optimize each speaker's performance in addition to providing protection against excessive sound levels and overheating.

The sound reinforcement system can operate on automatic mode for speech-only events for which a technician can plug in up to four microphones. The system optimizes microphone gain to prevent acoustical feedback. The sound system can be powered and automatic mode activated from a small control station located backstage.

The system also has a manual mode, employing a 32-channel mixing board (Mackie SR32-4 VLZ PRO) for more sophisticated performances. A transportable sound playback and electronic effects equipment rack accompanies the manual audio mixer. Both can be relocated from the control booth to an alternate location in the audience when needed. This is useful for rehearsals and allows more accurate sound mixing during actual performances with an audience.

Microphone and auxiliary (line) input jacks are distributed around the stage to allow easy connection of microphones and other audio signal sources.

Portable monitor speakers can be connected at many locations on and about the stage. Additional speaker connection points exist at the back of the house as well as at the overhead lighting catwalks above the audience to broadcast special performance sound effects.

A wired production intercommunications system links behind-the-scenes production personnel and others to distribute program production cues and other relevant information. The backstage area paging system employs ceiling-mounted loudspeakers and local volume controls to distribute sound within the green room, dressing rooms, the control booth, and other places. This system distributes voice pages originating from the production intercom system as well as performance sounds originating at the stage.

A dedicated paging system serves the lobby and public restrooms. It permits show patrons to be addressed directly from the sound control booth by voice for crowd notification and control. An electronic audience recall chime sound may also be broadcast to alert patrons that a show's intermission period is concluding. Performance sounds from the stage may also be distributed over this system.

A fixed central equipment cabinet, which contains system power amplifiers, processors, wireless microphones, hearing assist system transmitter, and other devices resides in the control booth that overlooks the stage.

Scattering Sound

Since a theatre's design can either add or diminish value from the performance of music — particularly classical music for band and orchestra — shaping, surface texture and finishes, and total volume all come into play. These affect both reflected sound — the direction and strength of the reflections — and reverberant sound.

The faster tempo of modern music such as jazz or a stage band does not require as great a room response as classical music. Classical music sounds best in a space where the sound persists for a longer time and surrounds the listener, creating a sense of envelopment. To achieve this sense of intimacy and clarity, it's critical to balance early energy from the sound that arrives at the listener's ears directly from the stage with late energy that primarily consists of the reverberant sound.

Early energy is created by a combination of direct sound from the stage plus reflections from the proscenium cheek walls and eyebrow reflector. The cheek walls and eyebrow reflector were shaped to produce a strong reflection to the entire audience area to create the needed early energy. The rearmost overhead reflector (where the sound is typically the weakest) also adds to the early energy, since the time delays of the sound from this reflector are very short. The result is a strong connection between stage and audience and clear music definition. As an added benefit, shaping the cheek walls in this manner helps reflect useful energy to the audience when an actor or musician is turned away from it.

Late energy, in the form of reverberation and corresponding envelopment, were increased in the design by raising the roof of the theatre to create more volume. Overhead reflectors in the middle portion of the house were decreased in size to expose the volume of the roof to the audience. These reflectors have a short radius to scatter sound that would otherwise reach the roof. The combination of the increased room volume and scattered reflections improves the strength of the reverberant field.

Audiences give higher marks to musical venues that have strong lateral energy. Lateral energy is created by sound that reflects to the audience from the side walls of the theatre. The shaping of the cheek walls that improves the early energy also creates the needed lateral reflections. To maximize the perception of the lateral reflections, the methods used to create sufficient late energy were also used to weaken the effect of the overhead reflections. Scattering some of the overhead sound creates multiple, weak reflections that shower the entire audience and create a more complex acoustic environment. The weaker, more complex overhead reflections allow the subtle lateral reflections to emerge.

A retractable curtain on the rear wall of the theatre was added to reduce the room response for speech and fast tempo music. This curtain can cover the back wall or be retracted above the rear reflector. The goal was to prevent late sounds from returning to the stage, thus reducing the reverberation time in the theatre.

Noise Reduction

At the school district's suggestion, the project team incorporated eco-charettes to explore sustainable design approaches for the center. These charettes led to the decision to install an under-floor air delivery system, in which air enters the theatre through grilles in the face of each seating riser.

An under-floor air delivery system produces air that is slightly cooler than the desired room temperature and significantly warmer than air that is delivered in a more traditional overhead duct system. It is virtually impossible to feel a cold draft due to the moderate temperature of the air conditioning. More air is needed to produce the same amount of cooling. To make sure the air movement is not perceptible, the velocity of the air out of the grilles is very low. Not only does this system increase audience comfort and reduce operational energy expenses, the low velocity of the air delivery reduces sound levels.

The acoustical design goal for the heating and ventilating system was to achieve a level of background noise that is unobtrusive in quality (frequency content) and low enough in level (amplitude) that it doesn't interfere with what's going on in the theatre. A plenum below the seating allows the air to be delivered at a very low velocity, which reduces noise and permits the subtle nuances of a performance to be heard clearly.

Community Connection

The delivery of this space has fueled collaboration between the school district and the members of the Bothell community, some of whom were weary of driving to nearby Seattle to enjoy the arts and others who needed local performance space.

“There was a huge demand for a real theatre that was not a gymnasium,” says Nikki Neuen, director of communications and marketing for the Northshore Performing Arts Foundation. “Local residents were hungry for a space to practice art. We are thrilled to have a space which serves the diverse interests of our community.”

Michael R. Yantis is a principal of Yantis Acoustical Design in Seattle. Email him at myantis@yantis.com.

NORTHSHORE PERFORMING ARTS CENTER SOUND SYSTEM

Microphones:

8 Shure Beta58A Vocal Mic
3 Crown CM-31 Choir Mic
2 Crown PCC-170 Boundary
1 Astatic 621L Handheld Lobby Page Mic
1 Astatic 202 House Monitor Mic
2 Shure ULXP14/85 Lavalier Mic System
2 Shure ULX2/BETA58 Handheld Mic/Transmitter

Playback:

1 Denon DN-T645 tape/CD/MP3 Player
Mixer:
1 IRP VM-4043 Automatic Mixer
1 Mackie SR32-4 VLZ PRO Main Mixer

Processing:

1 Shure P4800 Main Processor
1 Symetrix 322 DSP Monitor Delay Processor
1 Symetrix 421m AGC
1 Symetrix 532E Dual 1/3rd-Octave Equalizer
1 Rane ME15B 2/3-Octave Equalizer
1 dbx 166XL Compressor/Limiter
1 Yamaha REV100 Reverb/Effects Processor

Amplifiers:

1 Crown CH4
2 TOA A912Mk2 Backstage/Lobby Mixer-Amplifier

Loudspeakers:

1 Renkus-Heinz PN12/6-2(T) Dual Speaker Active Array (main)
1 TOA F-122CU Ceiling Speaker (Program/Paging)
1 Electro-Voice Eliminator Monitor E Portable Monitor/Effects Speaker
1 Mackie HR824 Booth Monitor Speaker

Racks:

1 Lowell L268-77 Main Rack
1 Lowell L258-36 Portable Effect

Hearing Assist:

1 Gentner TX-37A Transmitter
20 Gentner Digital 6 Receiver with Earbuds

Production Intercom:

1 Clear-Com MS232 2-Channel Master Station
7 Clear-Com KB211A Speaker Station
10 Clear-Com RS-501 Beltpack
12 Telex PH-1 Headset