Adapting to change
Jan 1, 1999 12:00 PM, Michael Garrison
Jubilee Christian Center, San Jose, CA, is on the forefront of contemporary worship and ministry. Dick Bernal, senior pastor, ministers not only to his own local congregation, but also to a national audience by hosting conferences and televising through Trinity Broadcasting Network, as well as internationally through evangelistic campaigns. Ron Kenoly, a singer/songwriter and prominent worship leader, is Jubilee's ambassador of worship. Jubilee is also a leader in the resurgence of the arts for the presentation of the Christian message. In addition to the charismatic style of the music worship services, there is a tapestry woven of dramatic presentations with traditional deliveries for the Word of the Lord.
When the time came for Jubilee to plan and build a new 3,200-seat sanctuary and world outreach center, the church leadership wanted state-of-the-art communication systems in a facility that suited the multi-faceted ministry. Richard Taylor, executive director of Jubilee Christian Center, served as a creative consultant to the design team. His background in video served the church's interest well because he was understanding of the church's special need to create a space friendly to the performance systems that remained comfortable to Jubilee's congregation.
The design team consisted of architect David Austin Smith of San Ramon, CA, Keith Lundquist of Lundquist Construction Management, San Jose, CA, and my company, Michael Garrison Associates (MGA), Fresno, CA, the project's acoustical, audio, lighting and video designer and consultant. Jubilee, having placed high confidence in MGA, granted us deference in the design work.
Unfortunately, the City of San Jose was not so sympathetic. After months of programming studies and preliminary design efforts, a conceptual design was selected that appeared to meet all of Jubilee's requirements. Early in the project's design development phase, the city unexpectedly imposed a roof height limitation of 37 feet (11 m), which had significant impact on the planned ceiling height and, consequently, upon the preliminary designs for the room acoustics, catwalk system, lighting system and loudspeaker systems. We had to scramble to come up with effective, affordable solutions.
Acoustics The restrictions resulted in an inadequate ceiling height and greatly reduced the initially planned room volume, which, in turn, threatened our efforts to provide an acoustical environment conducive to congregational singing. We suggested solving this problem by embedding RPG Omni-ffusors in quantities to approximate a 50% fill of the ceiling area. This required more than 1,200 units, and we were not sure that the owner or the architect would go for it.
We prepared computer renderings of this ceiling concept that were presented to the rest of the design team for discussion. Cost and feasibility studies were performed by Lundquist, which proved favorable to this design, and so the decision was made to use the Omniffusors.
Taylor said of this situation, "We were a little concerned when the diffusor ceiling design was initially proposed because we had never seen such an unusual ceiling panel. Because MGA told us this would be the best solution for our dilemma, and we were able to fit it in the budget, we decided to give it a go. The acoustics in our new auditorium are wonderful. Nearly everyone who comes into our church for the first time comments on what a neat ceiling we have."
The ceiling diffusors would help compensate for an inadequate reverberant field to the benefit of congregational singing, but this was not the only acoustical consideration. The demands of the musicians who attend Jubilee Christian Center also required acoustical conditions to be conducive to performance. To supplement the ceiling design, absorptive wall panels were specified for the side and rear walls as well as on the balcony face. This treatment, supplied by AVL Systems, Ocala, FL, reduced detrimental sound reflections to the stage area from the main loudspeakers and stage instruments.
Audio systems Design of the loudspeaker system was also impacted by the reduced ceiling height. Although satellite loudspeakers with signal delay were planned for the balcony areas, we had counted on clear line-of-sight to the main loudspeakers for all seating locations to create a proper sense of localization and to have as seamless as possible of a transition between the main and satellite loudspeakers. This was no longer possible. The situation mitigated against the church's criteria of uniform sound coverage to a high standard. This pressure forced us to consider some unorthodox solutions for this project.
David Kennedy, MGA senior audio designer, said, "To achieve uncompro-mised speech reinforcement in a space of this size, many factors are taken into account. Conventional thinking would dictate the use of high-Q, constant-directivity horn loudspeakers for such a room. Our observations are that although the individual horn loudspeakers may be a good solution in theory, they do not integrate well in array systems. Furthermore, the trade-off with these devices, in our opinion, has always been a degraded fidelity as compared to near-field loudspeakers, like those covering balcony and under-balcony seating. We expended a great deal of effort to explore alternatives for achieving a studio monitor quality of sound for the entire seating area without sacrificing intelligibility.
"We were attracted to Tannoy's Dual Concentric technology not only because of the reputation for superior fidelity and vocal articulation, but also because of the off-axis performance and power-handling capacity of the Super-Dual drive units," Kennedy said. "The Tannoy SuperDuals can reproduce detail in the program material at high SPLs, particularly the mid and high frequencies where critical detail must be maintained. The Dual Concentrics are widely spaced; thus, the mid- and high-frequency comb filtering is so dense that it is not perceived.
"From this foundation we were able to build the performance model of the loudspeaker array using polar simulation and JBL's CADP2 mapping programs. Applying dipole spacing and shading techniques, we determined the best relative location for each low-band drive unit within the cluster. This technique results in ideal low-frequency coverage with minimum spill on the stage. The resultant severe lobes in the mid-bass region are acceptable because the reverberant sound tends to fill in these direct-field cancellations."
The implementation of these concepts has led to a close working relationship between the two companies. MGA's design staff developed custom cabinet requirements and preliminary plans that were refined and built by Tannoy.
"The heart of this design is the relatively low-Q Dual Concentrics, which conventional thinking would dismiss for this reason alone," Kennedy said. "The fact remains, however, that these custom clusters deliver superior coverage uniformity, intelligibility and fidelity throughout the auditorium."
The Jubilee system consists of a main center (mono) cluster with outriggers, a stereo loudspeaker system, delay loudspeakers and a subwoofer system, all featuring Tannoy Dual Concentric and Superbass drivers.
These loudspeakers are driven by QSC PowerLite series amps, which are also a critical element in sonic quality. All major amps available today are reliable and, but I have observed that the PowerLite amps have a unique sonic quality that we and our clients definitely perceive and appreciate.
"Another crucial area for us is signal processing," said Brian Roggow, MGA systems designer and project manager. "We chose BSS Soundweb because of its reputation for sonic purity. Its Omnidrive units have been the practical benchmark for DSP for years, so we had great confidence."
The house and monitor mixing consoles were an important selection in which the Jubilee technical staff was included. Several major consoles were evaluated, and a 64-channel Midas XL-200 was chosen for the house location because of its user-friendliness and sonic characteristics. A 48-channel Allen & Heath GL-4000 was chosen as the monitor desk due to its cost-effectiveness and unique flexibility.
Lighting The church wanted the house lighting fixtures to be dimmable and to provide uniform coverage without glare. A total of 359 fixtures composed of six different models were required to achieve this performance. Kurt Versen, a manufacturer of premium light fixtures, was selected, because of the excellent non-glare characteristics of its units.
"We have difficulty seeing our house light fixture specifications through to completion," Paul Luntsford, lighting co-designer with PLA Designs, Aloha, OR, said. "Often, a well-meaning contractor promotes substituting a lesser equivalent to cut costs, and the client usually entertains these overtures. We have examples of other churches where this type of substitution was allowed with disastrous results. Therefore, we directed Jubilee to contact these other churches, and the battle was over."
ETC was chosen to supply the lighting dimming, control and distribution equipment, as well as the production lighting instruments. Two ETC Sensor SR48 dimmer racks were installed with a total of 96 dual 20 amp dimmer modules. An ETC Express main control console was provided with 72-channel two-scene operation or 144-channel one-scene operation. Convenience controls are through a number of Unison control stations. A total of 84 ETC lighting instruments were included in the package and supplemented by a number of the church's existing units.
Video Jubilee had high requirements for its new video systems. It also produced for a broadcast audience, are recorded to tape and edited in-house for broadcast prior to distribution. To enhance this aspect of their ministry, Jubilee's main platform features unique, dramatic set design of the Bay Area cityscape that combines commissioned paintings with 3-D models. The set helps create different moods and environments with special lighting effects. We designed a pipe grid for the stage area to provide maximum flexibility for locating lighting instruments, loudspeakers and other special effects units. This assembly, along with a vertical lift curtain, were provided and installed by Stagecraft Industries of Portland, OR.
Jubilee, in keeping with its commitment to excellence, purchased a package of broadcast-quality video equipment from Philips, including LDK-100 cameras and a D-10 digital switcher. These items were installed in combination with the church's existing video production equipment. The facility includes a video control room, an edit suite and an out-take studio that also serves as the pastor's lounge.
The video image serves not only the broadcast needs, but also the large-screen video projection and video monitor systems in the sanctuary. Image magnification and the projection of song lyrics, announcements, computer graphics and other video was important to Jubilee. We used computer modeling to help design this system and to optimize screen orientation to the viewers. An AutoCAD model was created by Tim Garrison, MGA's senior CAD designer, who then checked sightlines and viewing perspectives from various seating locations.
"We use 3-D computer modeling extensively in our design process," Tim Garrison said. "We learned a few years ago that this tool is not only useful to us for acoustic, loudspeaker, lighting and sightline studies, but also to our clients for visualizing significant architectural features."
Simple hidden-line perspective printouts and fully rendered color images were shown to the architect and church for discussion and decision making.
"MGA's design development architectural rendering services proved to be of much usefulness in planning and implementation and helped produce great results," Bernal said. Once the screen size and location was determined, Tim Garrison's next challenge was to work out the optical path for the projectors. Because there was not enough room for a straight shot, mirrors were required.
Jubilee wanted the highest quality image possible, so we recommended Hughes-JVC model 330S ILA projectors with a Faroudja LD200 line doubler to provide a 109x13.259 (254 mm x 337 mm) image on Stewart Filmscreen's Lumi-glass 180 screens-one on each side of the stage. A total of 20 Sony V22 27 inch (686 mm) monitors provide coverage to the upper balcony and lobby.
Summary Jubilee's new facility, completed in June 1998, stands as an example of modern church architecture with a careful blend of traditional values and high technology. These results could not have been achieved without the cooperation among the designers and construction staff, all of which was fostered and carefully nurtured by Jubilee. This, plus Jubilee's commitment to excellence and its original design priorities, resulted in the successful completion of this project.
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