Adapting to change
Jan 1, 1999 12:00 PM, Michael Garrison
Jubilee Christian Center, San Jose, CA, is on the forefront of contemporaryworship and ministry. Dick Bernal, senior pastor, ministers not only to hisown local congregation, but also to a national audience by hostingconferences and televising through Trinity Broadcasting Network, as well asinternationally through evangelistic campaigns. Ron Kenoly, asinger/songwriter and prominent worship leader, is Jubilee's ambassador ofworship. Jubilee is also a leader in the resurgence of the arts for thepresentation of the Christian message. In addition to the charismatic styleof the music worship services, there is a tapestry woven of dramaticpresentations with traditional deliveries for the Word of the Lord.
When the time came for Jubilee to plan and build a new 3,200-seat sanctuaryand world outreach center, the church leadership wanted state-of-the-artcommunication systems in a facility that suited the multi-faceted ministry.Richard Taylor, executive director of Jubilee Christian Center, served as acreative consultant to the design team. His background in video served thechurch's interest well because he was understanding of the church's specialneed to create a space friendly to the performance systems that remainedcomfortable 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 mycompany, Michael Garrison Associates (MGA), Fresno, CA, the project'sacoustical, audio, lighting and video designer and consultant. Jubilee,having placed high confidence in MGA, granted us deference in the designwork.
Unfortunately, the City of San Jose was not so sympathetic. After months ofprogramming studies and preliminary design efforts, a conceptual design wasselected that appeared to meet all of Jubilee's requirements. Early in theproject's design development phase, the city unexpectedly imposed a roofheight limitation of 37 feet (11 m), which had significant impact on theplanned ceiling height and, consequently, upon the preliminary designs forthe room acoustics, catwalk system, lighting system and loudspeakersystems. We had to scramble to come up with effective, affordable solutions.
AcousticsThe restrictions resulted in an inadequate ceiling height and greatlyreduced the initially planned room volume, which, in turn, threatened ourefforts to provide an acoustical environment conducive to congregationalsinging. We suggested solving this problem by embedding RPG Omni-ffusors inquantities to approximate a 50% fill of the ceiling area. This requiredmore than 1,200 units, and we were not sure that the owner or the architectwould go for it.
We prepared computer renderings of this ceiling concept that were presentedto the rest of the design team for discussion. Cost and feasibility studieswere performed by Lundquist, which proved favorable to this design, and sothe decision was made to use the Omniffusors.
Taylor said of this situation, "We were a little concerned when thediffusor ceiling design was initially proposed because we had never seensuch an unusual ceiling panel. Because MGA told us this would be the bestsolution for our dilemma, and we were able to fit it in the budget, wedecided 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 onwhat a neat ceiling we have."
The ceiling diffusors would help compensate for an inadequate reverberantfield to the benefit of congregational singing, but this was not the onlyacoustical consideration. The demands of the musicians who attend JubileeChristian Center also required acoustical conditions to be conducive toperformance. To supplement the ceiling design, absorptive wall panels werespecified for the side and rear walls as well as on the balcony face. Thistreatment, supplied by AVL Systems, Ocala, FL, reduced detrimental soundreflections to the stage area from the main loudspeakers and stageinstruments.
Audio systemsDesign of the loudspeaker system was also impacted by the reduced ceilingheight. Although satellite loudspeakers with signal delay were planned forthe balcony areas, we had counted on clear line-of-sight to the mainloudspeakers for all seating locations to create a proper sense oflocalization and to have as seamless as possible of a transition betweenthe main and satellite loudspeakers. This was no longer possible. Thesituation mitigated against the church's criteria of uniform sound coverageto a high standard. This pressure forced us to consider some unorthodoxsolutions for this project.
David Kennedy, MGA senior audio designer, said, "To achieve uncompro-misedspeech reinforcement in a space of this size, many factors are taken intoaccount. Conventional thinking would dictate the use of high-Q,constant-directivity horn loudspeakers for such a room. Our observationsare that although the individual horn loudspeakers may be a good solutionin theory, they do not integrate well in array systems. Furthermore, thetrade-off with these devices, in our opinion, has always been a degradedfidelity as compared to near-field loudspeakers, like those coveringbalcony and under-balcony seating. We expended a great deal of effort toexplore alternatives for achieving a studio monitor quality of sound forthe entire seating area without sacrificing intelligibility.
"We were attracted to Tannoy's Dual Concentric technology not only becauseof the reputation for superior fidelity and vocal articulation, but alsobecause of the off-axis performance and power-handling capacity of theSuper-Dual drive units," Kennedy said. "The Tannoy SuperDuals can reproducedetail in the program material at high SPLs, particularly the mid and highfrequencies where critical detail must be maintained. The Dual Concentricsare widely spaced; thus, the mid- and high-frequency comb filtering is sodense that it is not perceived.
"From this foundation we were able to build the performance model of theloudspeaker array using polar simulation and JBL's CADP2 mapping programs.Applying dipole spacing and shading techniques, we determined the bestrelative location for each low-band drive unit within the cluster. Thistechnique results in ideal low-frequency coverage with minimum spill on thestage. The resultant severe lobes in the mid-bass region are acceptablebecause the reverberant sound tends to fill in these direct-fieldcancellations."
The implementation of these concepts has led to a close workingrelationship between the two companies. MGA's design staff developed customcabinet requirements and preliminary plans that were refined and built byTannoy.
"The heart of this design is the relatively low-Q Dual Concentrics, whichconventional thinking would dismiss for this reason alone," Kennedy said."The fact remains, however, that these custom clusters deliver superiorcoverage uniformity, intelligibility and fidelity throughout theauditorium."
The Jubilee system consists of a main center (mono) cluster withoutriggers, a stereo loudspeaker system, delay loudspeakers and a subwoofersystem, all featuring Tannoy Dual Concentric and Superbass drivers.
These loudspeakers are driven by QSC PowerLite series amps, which are alsoa critical element in sonic quality. All major amps available today arereliable and, but I have observed that the PowerLite amps have a uniquesonic quality that we and our clients definitely perceive and appreciate.
"Another crucial area for us is signal processing," said Brian Roggow, MGAsystems designer and project manager. "We chose BSS Soundweb because of itsreputation for sonic purity. Its Omnidrive units have been the practicalbenchmark for DSP for years, so we had great confidence."
The house and monitor mixing consoles were an important selection in whichthe Jubilee technical staff was included. Several major consoles wereevaluated, and a 64-channel Midas XL-200 was chosen for the house locationbecause of its user-friendliness and sonic characteristics. A 48-channelAllen & Heath GL-4000 was chosen as the monitor desk due to itscost-effectiveness and unique flexibility.
LightingThe church wanted the house lighting fixtures to be dimmable and to provideuniform coverage without glare. A total of 359 fixtures composed of sixdifferent models were required to achieve this performance. Kurt Versen, amanufacturer of premium light fixtures, was selected, because of theexcellent non-glare characteristics of its units.
"We have difficulty seeing our house light fixture specifications throughto completion," Paul Luntsford, lighting co-designer with PLA Designs,Aloha, OR, said. "Often, a well-meaning contractor promotes substituting alesser equivalent to cut costs, and the client usually entertains theseovertures. We have examples of other churches where this type ofsubstitution was allowed with disastrous results. Therefore, we directedJubilee to contact these other churches, and the battle was over."
ETC was chosen to supply the lighting dimming, control and distributionequipment, as well as the production lighting instruments. Two ETC SensorSR48 dimmer racks were installed with a total of 96 dual 20 amp dimmermodules. An ETC Express main control console was provided with 72-channeltwo-scene operation or 144-channel one-scene operation. Conveniencecontrols are through a number of Unison control stations. A total of 84 ETClighting instruments were included in the package and supplemented by anumber of the church's existing units.
VideoJubilee had high requirements for its new video systems. It also producedfor a broadcast audience, are recorded to tape and edited in-house forbroadcast prior to distribution. To enhance this aspect of their ministry,Jubilee's main platform features unique, dramatic set design of the BayArea cityscape that combines commissioned paintings with 3-D models. Theset helps create different moods and environments with special lightingeffects. We designed a pipe grid for the stage area to provide maximumflexibility for locating lighting instruments, loudspeakers and otherspecial 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 packageof broadcast-quality video equipment from Philips, including LDK-100cameras and a D-10 digital switcher. These items were installed incombination with the church's existing video production equipment. Thefacility includes a video control room, an edit suite and an out-takestudio that also serves as the pastor's lounge.
The video image serves not only the broadcast needs, but also thelarge-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 usedcomputer modeling to help design this system and to optimize screenorientation to the viewers. An AutoCAD model was created by Tim Garrison,MGA's senior CAD designer, who then checked sightlines and viewingperspectives from various seating locations.
"We use 3-D computer modeling extensively in our design process," TimGarrison said. "We learned a few years ago that this tool is not onlyuseful to us for acoustic, loudspeaker, lighting and sightline studies, butalso to our clients for visualizing significant architectural features."
Simple hidden-line perspective printouts and fully rendered color imageswere shown to the architect and church for discussion and decision making.
"MGA's design development architectural rendering services proved to be ofmuch usefulness in planning and implementation and helped produce greatresults," Bernal said. Once the screen size and location was determined,Tim Garrison's next challenge was to work out the optical path for theprojectors. Because there was not enough room for a straight shot, mirrorswere required.
Jubilee wanted the highest quality image possible, so we recommendedHughes-JVC model 330S ILA projectors with a Faroudja LD200 line doubler toprovide a 109x13.259 (254 mm x 337 mm) image on Stewart Filmscreen'sLumi-glass 180 screens-one on each side of the stage. A total of 20 SonyV22 27 inch (686 mm) monitors provide coverage to the upper balcony andlobby.
SummaryJubilee's new facility, completed in June 1998, stands as an example ofmodern church architecture with a careful blend of traditional values andhigh technology. These results could not have been achieved without thecooperation among the designers and construction staff, all of which wasfostered and carefully nurtured by Jubilee. This, plus Jubilee's commitmentto excellence and its original design priorities, resulted in thesuccessful completion of this project.