21,000 Seats, But Who's Counting?

An Awe-Inspiring Design for the New Latter-day Saints Conference Center in Salt Lake City

It's hard to picture an auditorium with 21,000 seats. That's more than 10 times the size of your average Broadway theatre, and almost four times the size of Radio City Music Hall. But the multipurpose auditorium in the new Conference Center for the Church of Jesus Christ of Latter-day Saints in Salt Lake City, UT, is just that: 21,000 seats in a sweeping, fan-shaped configuration that is quite awe-inspiring.

The design of the complex, which opened in April 2000 and was dedicated last October, was a joint venture with an architectural team from Zimmer Gunsul Frasca Partnership (based in Portland, OR), working closely with Latter-day Saints architects Leland Gray and Kerry Neilson and the team of San Francisco-based theatre consultants from Auerbach + Associates, headed by S. Leonard Auerbach. The firm of Jaffe Holden, based in Norwalk, CT, served as acousticians, with architectural lighting by Auerbach + Glasow, a division of Auerbach + Associates.

The large theatre is the focus of the 1.5-million-sq.-ft. Conference Center, which occupies an entire 10-acre lot adjacent to Temple Square in downtown Salt Lake City. The sprawling white complex also features a 911-seat proscenium theatre, and a 1,400-car underground parking structure. The goal of the architects was to have the new building honor the physical, historical, and spiritual significance of the Temple and other buildings within Temple Square.

“The intent of the architecture is to transform the building into landscape by creating a series of terraces that respond to the dramatically sloping site. The solution essentially doubles the size of the urban park-like quality of Temple Square; the terraces create a garden setting that enables the building to participate in the life of the city throughout the year,” says a brief from the architects.

“This is the largest project we have ever worked on,” says Len Auerbach, principal in charge of design for Auerbach + Associates. “I was teaching a theatre design seminar at Harvard one summer, and architects Leland Gray and Kerry Neilson, who are members of the Church, were participants. They approached me and asked if I was interested in seeing what they were doing.”

This was in 1995, when Auerbach came onboard as theatre consultant for the project. “On their laptops they had a project for a large space under a dome, and we started talking about the effectiveness of domed structures. They needed input from a theatrical point of view.”

Interestingly, the Latter-day Saints Church has its own design department that oversees the construction of several buildings each year. But this was to be the biggest one ever, designed to house the semi-annual General Conference, held in April and October, which draws 50,000 people, and features live pageant productions. The new auditorium dwarfs the Tabernacle at Temple Square, former home of the General Conference, which seats a mere 6,000 people.

Auerbach was not only a good fit for the project, but he had also worked with the Church's project manager, Thomas E. Hanson, on several projects in San Jose, CA. “They wanted a space to hold their General Conference, their main time of communication with their members,” notes Auerbach, who designed various configurations of anywhere from 18,000 to 30,000 seats before the final number was settled upon. The events at the two-day, five-session General Conference are broadcast worldwide via satellite in multiple languages to over 50 countries, so the facility also required a state-of-the-art broadcast facility.

Not a Sports Arena

“Our prime objective was to get 21,000 people into one space without having it look like a sports arena,” says Auerbach, whose team included Tom Neville as project manager. “The goal was to get their message across and design a building that is meant to last for 150 years,” Neville adds.

In order to get an idea of the production requirements for the large indoor pageants, the Auerbach team, including design principal Steve Pollock, went to Palmyra, NY, birthplace of the Mormon religion, and where the large, outdoor Hill Cumorah pageant draws 10,000 people each summer. “We looked at how they staged this pageant, which has 500-600 people onstage, and at how the performers got into place.” Of course the sightlines and technical requirements for a large indoor space would be quite different, but the Palmyra pilgrimage gave the theatre consultants a taste of what was waiting in the wings.

The auditorium itself, although amazingly large, has a surprising sense of intimacy and warmth. The beige walls and ceiling treatment contrast with reddish-brown seats, supplied by Irwin Seating of Grand Rapids, MI, and carpeting of the same color. The seats for the choir are upholstered in mohair; those for the audience are a blend. “The focal point of the room,” says Neville, “is a single person speaking, so we needed a large fan rather than an oval shape.”

Computer renderings and 3D drawings of critical elements were made by the team at Auerbach to calculate the scale of the building so that everyone involved would understand where all the systems had to go. “In spite of its large size,” says Neville, “we had to get the technical systems and ductwork into the same space. It is like a large jigsaw puzzle and parts of it are very complicated. The individual pieces are pretty straightforward, but the whole thing is so large.”

Pollock, a vice president at Auerbach, worked on the seating configurations so that no seat is more than 270' from the pulpit. He also worked to create interesting and workable circulation paths. “The pageant in Palmyra is a major social event,” notes Auerbach. “The audience is greeted by missionaries who talk to you about the Church, so we couldn't deal with this as a normal theatrical space where you just go in and out.”

As a result, the auditorium is designed with cross-aisle concourses, which allow audience movement and break up the blocks of seats. “Even with 21,000 people, the hall can empty in 10 minutes,” Auerbach adds. “There are lots of exits. The audience flow and circulation work very well. And as the hall empties, another 21,000 people are waiting to enter.”

One of the first requirements for the auditorium was seating for the 352-voice Mormon Tabernacle Choir and a rostrum for a 158-member general council. “If we had made this a permanent structure, it would have been as high as a five-story building,” points out Auerbach, adding that the seating units can be removed to provide a flat floor for the pageant productions. When the auditorium moves into pageant mode, the first 40' of seating moves away so that the stage area can be extended.

The end result is a rostrum made of aluminum and steel paneled in cherry wood, and built by Stageright of Claire, MI, that measures 150' wide, 80' deep, and 30' high. It is designed to be demountable and moved offstage in modular sections that weigh up to 10,000lbs and are mounted on air casters to facilitate movement into upstage storage bays. A computerized chain hoist system with hardware by JR Clancy of Syracuse, NY, moves the sections as they are suspended and stacked behind Auerbach-designed walls, 20' wide by 70' tall, which open and close on a single pivot point.

Attacking the large space from a theatrical standpoint, Auerbach + Associates designed a structural steel grid that sits 90' above the stage, rostrum, and backstage areas (a combined space roughly 250' × 150", or half the size of a football field). The grid accommodates an automated variable-speed rigging system with 40 motorized point hoists installed to date (the system can be expanded to include another 30 points in the future).

“This allows them to fly 1,000-2,000lb scenic elements anywhere over the area, or combines to lift larger loads,” says Auerbach. The computerized control relies on the Nomad Motion Control System from UK-based Stage Technologies. Hand-carried remotes allow technicians to operate the hoists (some of which are used to move the rostrum modules).

In front of the rostrum are two large columns, 8' in diameter that support what Auerbach calls the “king” truss, which is over 150' long and 32' high. From this, there are 10 radial trusses that stretch from the king truss to the radius wall approximately 300". “All the other elements tie into the king truss,” explains Auerbach.

Power of the Spoken Word

For Christopher Jaffe and the team of acousticians from Jaffe Holden, the challenge was to take such a large environment and have it respond to the human voice, and work well as a performance venue for the choir, orchestra, and the pageant (which is prerecorded). “Our two goals were rather oppositional,” notes Byron Bishop, project manager/sound system, for Jaffe Holden. As the space is often used with just one person speaking at the pulpit, the sound is all about the spoken word.

“For this it needs to be intimate, so the acoustics were designed with a short reverb time, like a lecture hall,” says Bishop. “But for performances by the Mormon Tabernacle Choir, a longer reverb time is needed.” To meet these dual requirements, the reinforced sound system for one voice uses a distributed system, putting the speakers as close to the people as possible. For music, they add reverb using Jaffe Holden's patented ERES (Electronic Reflected Energy System), which emulates natural reflections.

“In effect there are two distinct systems,” says Bishop. “Crisp and clear for the spoken voice, and a more acoustic environment that gives the sense of being in a concert hall with reflective surfaces.” The center cluster has four EAW MH433 and one EAW LDS 812 (custom) loudspeakers, and is placed directly over the pulpit. “This can be a big problem, as the speakers are in a direct feedback path, so we use DSP manipulation to keep the sound off the podium and avoid feedback,” says Bishop. “We did some beam steering to move blocks of sound around. You can do beam steering anyplace in the room.”

There are over 400 loudspeakers in the auditorium, in the following positions: tech column arrays (four EAW KF860s, eight EAW KF861s, and two EAW KF695s); over orchestra ring (19 EAW 7672 JHSes); over/under balcony rings (34 EAW ASR690 JHSes); rostrum (120 EAW SL12 customs, 150 EAW BB-4T customs, and 30 EAW UB22s); ERES speakers (139 EAW ES621s, 134 LARES 440s, and 58 EAW SB180PD1s).

The loudspeakers are driven by a variety of QSC CX Series amplifiers, while DSP is provided by four Peavey MM980NT units fully loaded with DSP cards. Mixing is done by two Soundcraft Series 5 consoles with one Soundcraft Series 5 Monitor and one Yamaha 01V console. The mixing position is located in the middle of the auditorium floor, yet recessed as not to block sightlines. Racks of audio gear are built in under the seats behind the consoles.

Since there are no hard surfaces around the choir members, they could not hear themselves sing, so small custom speakers were added to their chair backs as monitors. “With the ERES, we were able to create an environment just for the singers,” says Bishop, who spent 14 days on site calibrating and tuning the sound system, which was installed by SPL Integrated Solutions, a PRG company. “I got a pedometer and logged 76 miles walking around the building in those two weeks,” Bishop adds.

World's Largest Lighting System

The theatrical lighting system was designed by the Auerbach team as a continued development of the networked system by Strand Lighting they had specified for the San Francisco Opera House a few years ago. “The client wanted an assurance that what we did was going to work, and they asked us to use proven technology — no prototypes and no products under development,” Auerbach says.

In this case the lighting system was provided by ETC (Electronic Theatre Controls in Middleton, WI), and in spite of a no “vaporware” clause, a new control console was developed for the job, based on ETC's Obsession II with new software. “This is the largest theatrical lighting system we know of in the world,” says Auerbach. There are 6,000 control circuits in the building and a central network for the theatrical and architectural systems, the large auditorium, and the smaller theatre.

It is designed as a fully redundant control network, which has two streams of the same information running in a parallel manner with separate conduit runs. This way there is a dedicated backup so that the system cannot fail. “If they go offline, they go off to the entire world,” says Auerbach. A UPS power supply is followed up by a generator (all of the lighting control is powered from UPS circuits, and the UPS units are backed up by a generator). The system was provided by Justesen & Associates of Salt Lake City.

Working as a subcontractor to the general contractor (Legacy Constructors), ETC provided onsite project management, R&D engineering, and technical services required for contract completion. “I began traveling to the site on a regular basis shortly after we were awarded the project to begin coordination with both the electrical contractor [GSL Electric] and Legacy,” says Robert Degenkolb, project manager for ETC. “We worked very closely with GSL's engineers to ensure that cable paths and load-wiring requirements were understood and accounted for, and that GSL had the required information for proper MEP coordination.”

ETC was also involved in onsite and offsite mockups, including a late-night fixture test from the catwalks (where they found that the 5∞ Source Four worked more as a washlight because of the throw distance) and an offsite ceiling mockup distribution hang. “The early engineering was one of the most creative elements of the project, as we were trying to determine how we were going to get all of the stuff installed in the building within the time constraints of the project,” Degenkolb says. “The end result was that a number of installation and mounting methods were developed specifically for this jobsite.”

The system is composed of redundant network routers connected via fiber-optic cable to network switches located in various control and dimmer rooms throughout the building. The switches are responsible for sending the proper ethernet information to the ETCNet2 DMX nodes, some of which are dedicated to outputting DMX512 information to the dimmer racks. Level information is input to the system by way of several Obsession II DPS systems and Unison Architectural control systems with LCD touchscreens. Additionally, WRFUs (wireless remote focus units) allow the operator to control individual light levels from anywhere in the hallway.

The “fully redundant” aspect of the lighting system means that any major control element (including network routers and switches, as well as Obsession processors and ETCNet2 DMX nodes) can fail without the lights going out. Everything up to the output of the ETCNet2 DMX Node is on a TCP/IP network, and third-party equipment (Cisco Systems) is responsible for resolving the network redundancy. Redundant Obsession processors and ETCNet2 DMX nodes are provided, and almost every dimmer in the facility receives DMX signal from two separate DMX nodes. The fiber and UTP cable plants were engineered and installed to support this level of redundancy throughout the facility.

ETC field service technicians Tony Walla and John Hessler temporarily relocated to Salt Lake to supervise and direct the installation of the dimming, distribution, and control systems. The complete theatrical and architectural control system was mocked up by ETC R&D and system engineers Ed Prasser, Karen Meuth, Dan Hilstead, and Dan Talajkowski in an offsite facility. “This provided us the opportunity to configure and test the entire system in a controlled environment, which led to a seamless migration and installation of equipment in the Conference Center,” says Degenkolb.

The size of the building required extremely long signal distribution runs (often as long as 2,000"). There are four large dimmer rooms nestled high among the trusses for the more than 4,200 ETC dimming and relay circuits in the main space alone. Access to the lighting locations is via 700' catwalks that run from support wall to support wall.

On Air

Since the proceedings of the General Conference are broadcast worldwide, the lighting must adapt quickly to television standards. Veteran television lighting consultant Bill Klages was brought in to design a broadcast plot, which was integrated into the overall plot for the auditorium. Large video screens (29' × 21") flank the rostrum and can retract into the ceiling when not in use. The rigging for these is an Auerbach design with hardware by Clancy.

A complete HDTV studio was installed by the New Jersey-based IMMAD, with a fiber-optic connection to the local broadcaster that does the uplink for satellite broadcasts. In the main auditorium, robotic camera pylons telescope up and down so they can be concealed in the floor for non-broadcast events. Also with the television broadcasts in mind, the speaker's pulpit has a remote-controlled variable height so that the television shot looks the same no matter how tall the speaker might be.

The “Smaller” Space

The 911-seat theatre is a fully equipped proscenium theatre designed for musical theatre or touring productions, as well as an overflow for the large theatre, and has an orchestra pit for up to 35 musicians. The ETC lighting system has over 700 theatrical and architectural dimming and relay circuits, including five dedicated 64' electrics and an array of network equipment, plus an ETC Obsession II DPS system provided by Justesen & Associates. Rigging hardware, including general-purpose linesets, light ladder side battens, side-stage tab battens, onstage electric battens, a stage fire curtain, white sharkstooth scrim, and a 400-sq.-ft. orchestra lift, was all provided by Texas Scenic. The stage in this space measures 110' wide by 48' deep, with a gird 75' above the stage with 61 permanent counterweight linesets. The orchestra pit lift can be used to reconfigure the stage front as an apron or for additional seating.

“The lighting system in the smaller theatre is on a separate network that is ‘tied’ to the large theatre and lobby lighting systems,” explains Degenkolb. “What this really means is that it can operate independently or as part of the rest of the system. Yes, you can sit in the main control room and control all of the theatrical and architectural lighting throughout the facility. We — as well as Utah Power and Light — just don't recommend you type “Dimmers One through 8192 at full enter.'”

The architectural lighting package, designed by Auerbach + Glasow, includes over 1,100 interior fixtures with 20 different custom designs. Winona Lighting provided the majority of the custom interior fixtures, including sconces and pendants for the main lobby; additional custom fixtures were provided by Shaper Lighting, Taylor/Stokes, 3D Art. Standard fixtures are by Kurt Versen, and Translite, while lighting for the restrooms includes sconces by Boyd Lighting and vanity lights by Neoray. Custom exterior fixtures, including decorative poles and units, arcade sconces, and decorative lighting bollards, were manufactured by Sterner Lighting. Standard fixtures were provided by Bega, Lightolier, and Shaper Lighting. Outdoor fountains are lit with Hydrel fixtures and Fiberstars fiber optics.

The architectural lighting design adds warmth and intimacy to the space, with fixtures selected to address the criteria of Church tradition and universal appeal. “The design of the custom fixtures was a collaborative process beginning with our sketch ideas and those of the architects. This led to our design studio developing every detail from the glass to the fasteners,” says Patricia Glasow, vice president of Auerbach + Glasow.

Somewhere in the Mormon scriptures is a prophecy that one day they would have a building so big there will be trees and water on top of it. Coincidentally, there is a 75' height restriction for buildings in Salt Lake City, so part of this new complex is built into the hillside, providing access to the roof where the architects have built a plaza with fountains and trees. Divine planning, some might say.

Click here for a credits and partial equipment list.