Volume control at U T: A mammoth 45-foot-wide, 17-foot-tall loudspeaker cluster pumps up the volume to compete with vocal Vols fans.

Jul 1, 1997 12:00 PM, Brian Blackmore

When more than 100,000 people congregate in any one place, the sound system is going to have a tough time competing. When those 100,000 people are orange-clad, football-obsessed enthusiasts of the Volunteers at the University of Tennessee, odds for sound that is loud enough and still intelligible get even longer. Yet that goal was met in a sound-system redesign that would make any consultant proud.

UT's Neyland Stadium in Knoxville has undergone 14 expansions since the field was built in 1921, and this latest expansion is probably the last. Last summer 10,000 seats were added to the newly constructed canopied upper deck area in the north end zone, bringing the actual seating count to 102,544. This addition required the dismantling of the existing end-zone loudspeaker cluster. The architects for the stadium project, Neyland Stadium Designers, located in Knoxville, TN, contacted renowned acoustical consultants Coffeen, Fricke & Associates in Lenexa, KS, to design a new sound system. Coffeen, Fricke & Associates' latest projects include Ikeda Auditorium and Makiguchi Hall, Japan, the Deustche Bundestag in Germany, and Dulles International and Washington National airports in the United States.

Goals and timetables The project team at Coffeen, Fricke & Associates included John Fricke, John Ledo and Jill Elmers. Their goal was to provide clean, intelligible, high-level sound throughout the stadium for more than 100,000 screaming UT fans.

"Today's audiences expect intelligible sound," said Fricke, president of Coffeen, Fricke & Associates. "Given the noise level in this stadium, speech intelligibility was our major concern."

As with many stadiums, the architecture limited the possible locations for mounting the main loudspeaker cluster. Ledo, the team leader, designed the sound system with the main loudspeaker cluster placed on top of the stadium's huge press box. Having the center loudspeaker cluster positioned at mid-field presented Ledo with some unique challenges as to pattern coverage, low-frequency dispersion, the configuration and angling of the high-frequency horns and coverage for the under-balcony areas, canopied upper-deck seats and the seats directly below the press box.

Ledo's system design was presented and approved. Subsequently, in an attempt to amortize the cost of the system over two years, the officials at UT decided to implement Ledo's design for the new loudspeaker cluster and north end-zone loudspeakers in 1996, and complete the loudspeaker installation in east, west and south zones the following year. What ensued was fairly predictable. UT fans seated in areas covered by the new sound system were ecstatic about the intelligibility of the game's announcer and the power and clarity of the music. On the other hand, the fans located in the non-renovated sections quickly became disgruntled with the poor sound emanating from the existing loudspeakers. They bombarded the athletic office at UT with phone calls, asking when their sections would have better sound. After the second home game, the officials at UT decided to make all the fans happy and have the remainder of the loudspeakers installed before the third home game on Oct. 26th.

Bigger and better The new sound reinforcement system at UT is impressive in both size and capacity. One of the major concerns was low-frequency directivity within the cluster. Ledo evaluated several possible low-frequency cabinets, and after careful acoustical evaluation, decided to use Altec Lansing's massive, horn-loaded bass cabinets. Sixteen Altec Lansing 817B cabinets were customized and outfitted with two 515-G-series woofers, fiber-glass coated and fitted with weatherproof grilles. Designed to perform in venues where directivity control at low frequencies is critical, these horn-loaded systems provide performance advantages not found in ordinary bass systems.

"We were fortunate to work with a manufacturer like Altec Lansing - a company that has the freedom and ability to customize their components easily and efficiently," noted Fricke.

For high-frequency coverage, 20 Electro-Voice large-format HP horns were strategically positioned in a three-tiered loudspeaker cluster to cover the playing field and the stands. Chosen for their constant directivity and smooth frequency response, HP series loudspeakers control directivity down to 500 Hz.

The main loudspeaker cluster is 45 feet (13.7 m) wide, 17 feet (5 m) tall and sits on top of the largest press box in the country. This mammoth press box itself is 300 feet (91.5 m) wide, four stories tall and 50 feet (15.2 m) deep. It serves not only as a press facility but also as home to a number of private boxes and suites. The top of the press box, where the main cluster sits, measures the full width of a football field. The cluster is so large that a section of the stadium's lights had to be moved and reset to accommodate loudspeaker placement. With a total of 32 bass loudspeakers and 39 high-frequency drivers, this cluster produces 75% of the sound for the entire stadium.

The main cluster is divided into three sections with three tiers of loudspeakers housed in each section. The center section has four low-frequency cabinets across the bottom row, an HP9040 horn, two bass cabinets and an HP6040 in the second row, and two HP4020 horns flanking either side of the two bass cabinets across the top. This center grouping sits perpendicular to the stadium.

The two end groupings of the main loudspeaker cluster are mirror images of each other, with the Altec Lansing 817B bass cabinets angled 15% off the center line and the HP horns angled to reach the far north and south end zones. Each of these side groupings contain four Altec bass cabinets with an Electro-Voice HP6040 and HP4020 horn positioned on either side on the bottom row; two HP4020s, one HP6040 and two bass cabinets are in the center row; and an HP6040 and two HP4020s are on the top row. Nineteen of the horns are loaded with Electro-Voice DH1A/2MT dual large-format, high-frequency compression drivers; the remaining horn has a single DH1A driver. In addition to the main cluster, two HP6040s are hung under the light truss on the right hand side of the main cluster and angled to cover the outermost seats the main cluster could not reach.

A total of 294 Electro-Voice S-60T loudspeakers are used throughout the under-balcony areas of the stadium. The S-60Ts are mounted singly or in groupings of twos and threes, depending on coverage patterns. Two areas required additional loudspeaker support: the canopied area in the upper north end zone, and the section directly below the press box. Four Electro-Voice PI-100 loudspeakers were used to cover the largest distance between the seats and upper north end zone roof deck; a number of single S-60Ts cover the shorter distances. To reach the fans sitting directly under the press box, 55 MG 820 CX coaxial loudspeakers were flush-mounted underneath.

Getting the job done Sound system contractor for the project is Lowrance Sound Company, located in Union City, TN. This is the third project Lowrance Sound has done with Coffeen, Fricke & Associates; the two companies already collaborated on the 65,000-seat North Carolina State football stadium and the University of Tennessee's Martin Physical Education Complex. Mark Lowrance, president of Lowrance Sound, spearheaded the installation.

Working closely with John Ledo, Lowrance displayed exceptional organizational capabilities. One of the first issues Lowrance dealt with was how to raise the main loudspeaker cluster to the top of the Neyland Stadium press box, more than 300 feet (91.4 m) above the field.

"To set the bass cabinets on top of the press box, they had to be raised not only over the press box, but over the lighting towers as well," said Lowrance. "Working with Ray Bell Construction, Neyland's general contractor, we found the largest crane available in a five-state area. This $1.5 million, 300-ton Krupp crane lifted the steel frame that holds the cluster in place. It was lifted in a day and a half, and the bass cabinets were lifted in only three hours. Good planning always pays off. We began the lift at 1 p.m., and at 4 p.m. I walked into the construction office and told the site manager we were through with the crane. They couldn't believe we had lifted and anchored all the bass cabinets in three hours."

Although the top of the press box supports the main loudspeaker cluster, the control and rack rooms are located on various floors of the press box itself. Most of the processing gear and all the amplifiers are housed in 12 racks, each 77 inches (2 m) tall, in a newly configured third-floor amp room. System front-end processing includes four White 4702 dual-channel programmable equalizers, two Electro-Voice XEQ-2 electronic crossovers, 10 Electro-Voice DDL-204 electronic signal delays with optional input and output transformers, a Yamaha D1030 crossover-processor and four Symetrix 501 compressors.

Powering the system are a total of 54 Electro-Voice AP-series amplifiers. Ten AP2600A/SA and two AP2300SA dual-channel amplifiers drive the high-frequency horns. Each of these channels is outfitted with DSTR tweeter protectors in custom rack mounts designed and constructed by Lowrance Sound to protect the HF drivers from excessive long-term power input. The bass drivers in the main cluster are powered by 16 Electro-Voice AP3200s. Eleven Electro-Voice AP2600A/SAs, two AP2300SAs, and 13 AP3200s drive the delayed and distributed loudspeaker circuits. Each of these amplifiers has a custom output panel with either an AT100 or AT300 autoformer matching the amplifier outputs to the actual line loads. Lowrance designed and constructed custom panels for both input and output devices as well as the tweeter horn protectors.

"In this installation, the rack wiring is a work of art," said Fricke. "It's one of the best installations I've seen in years."

The press box control area is located on the fifth floor and divided into three separate levels: The top level accommodates sound-system operations, the center level is dedicated to the scoreboard, and the game announcer and support team occupy the lower level. The sound system operation level is equipped with a Tascam compact disc, cassette deck and a Symetrix 425 compressor-limiter. A Mackie 1604VLS mixer controls all inputs. Other rack-mounted equipment includes a LynTech Crowd-Comp level-compensating device, a White 4702 equalizer for the wireless systems, an Oxmoor buffer amplifier and an audio distribution amplifier. Electro-Voice DO56 microphones on specially designed CFA stands are used by the game announcers. Electro-Voice RE11s serve as field mics; the game referee uses a Vega U2020 UHF lapel system.

"When we first got this project, we were both happy and somewhat apprehensive. With two other projects that had fall completion dates, we were short on time and personnel," said Lowrance. "But as it turned out, everything went so well, it was almost scary. The initial installation was finished 30 days ahead of schedule and everyone was delighted with our work. After the final delay loudspeaker installation in October, fans in the stadium seating area hear much better than before. Special thanks goes to the folks at Electro-Voice and Altec Lansing, and their reps, Wally and Brent Wilson, from Wilson Audio Sales. Without everyone's cooperation, this project could not have finished early or gone so smoothly."