Venue Sound, Part 2: The Technology Story

It all started in church. The house-of-worship market, as it’s known in the pro-audio business, began demanding a new level of performance in large sound systems about two decades ago, coincident with the rise of the mega-church. These massive facilities, which can seat several thousand worshippers, had two key requirements: high intelligibility for speech, to allow pastors to be understood amidst the reverberant interiors of these immense venues, and full-range frequency capability, to better project the rock bands that were part of the shift to contemporary worship styles. As sound-system manufacturers realized the potential of this huge burgeoning market, they were spurred to product innovation, accelerating the use of line arrays that had previously been used mainly in touring sound and were now becoming part of the installed-sound technology arsenal.

Some observers believe that the church market’s demand for better sound was prompted by the arrival, in the late 1970s, of Dolby and THX cinema-sound technologies. But there’s no doubt that the next big market to benefit from these high-performance sound systems was sports venues. The rebuilding and expansion of major-league stadium and arena infrastructure over the past two decades took the sound-system business along. Of all sports-venue AV renovation projects, the leading type is sound.

Not surprisingly, manufacturers began by adapting existing products for the sports-venue market and then built dedicated systems for it. Brad Ricks, applications expert at JBL, says his company developed the PD700 point-and-shoot line of enclosures in 2000 specifically for larger arenas and stadiums. Its first installation was at Ford Field for the Detroit Lions.

“Before that,” he explains, “we and the few other companies that had targeted this market early on were using existing three-way systems that we also sold into other types of venues, like performing-arts centers.”

Ricks, who previously had worked at sports-AV design consultancy WJHW, notes that this new market had its own demands for sound systems. They needed to be louder, as much as 100-plus dB, to fill ever larger venues and, in the case of point-source systems, throw distances as far as 750 ft., and they had to have improved directivity, to better steer the sound away from reflective surfaces that would impair intelligibility and keep it contained in the bowl and not waste the energy needed to produce the new volume levels (or generate noise complaints from the surrounding community). That led, he says, to dedicated venue systems like JBL’s VLA line-array system. A beta version of that system was installed at Chicago’s Soldier Field in 2003 and was so successful that it was productized three years later and is now installed in 25 sports venues, 13 of which are end-zone systems.

The Market Takes Off
JBL’s experience mirrored that of other companies, such as EAW, which were early entrants in the sports-venue market. The growth of the market was initially in major-league and top-tier college sports but more recently has been seen in other collegiate markets and even secondary schools — there are two VLA systems installed in high school stadiums in the U.S. And it has drawn a raft of other manufacturers, with both dedicated and adapted systems, particularly for indoor venues, which do not need harder-to-manufacture weatherized speaker components.

L-Acoustics, for example, a provider of sound systems for music touring, has expanded its presence in sports recently. According to National Manager for Installation Projects Dan Palmer, sports is spearheading an important area of the company’s installed-sound division, and systems have been installed in several NHL arenas, including the Phoenix Coyotes’ Jobing.com Arena and the Vancouver Canucks’ Rogers Arena. The Marriott Center in Provo, UT, home to the BYU Cougars basketball team, recently installed an L-Acoustics KARA line-array system to support another aspect that sports venues have had to develop: multi-use capability, specifically to support touring music acts, theatrical performances, and corporate events.

“Sports venues now are looking for the full entertainment package,” says Palmer. “They want high intelligibility for announcements during games and life safety, and they want the sound systems to be musical. They want impact, clarity, and imaging. And, as the video systems get bigger, that’s upping the ante for sound: both have to have higher resolution. That’s part of what’s driving product development now. Sports is entertainment, and the sound has to keep up.”

Problems in the Mix
However, all that added volume has had implications for broadcast sound. At the same time that sports-venue sound has become more focused inside the arena or stadium and louder in the process, sports-broadcast audio has been adding more microphones to create larger surround-sound fields. Unfortunately, those two trends are starting to conflict.

“It’s all becoming just too loud,” complains Phil Adler, a veteran A1 for NFL and NBA broadcasts. “The constant barrage of fan prompts and other sound through louder PA systems makes it impossible to filter out all the noise with all of the microphones we now have out there. The sound is great, it’s clean, and the low end is great, but, ironically, that’s making it a bigger problem. I can’t compete with all of the sound they’re putting into the stadiums and arenas. It’s getting into the broadcast sound more than ever.”

All sports have gotten louder in recent years, a result of PA-technology advances, but some of that sound is less easily managed in some types of venues. NFL games can be extremely loud, but Adler points out that the use of the PA system is usually at least predictable.

“The league won’t let the PA be used during play, so we have a chance to bring the faders down ahead of a postplay announcement,” he says.

But, he adds, sometimes the PA announcer or on-field referee will pipe up faster than expected, piling on to already full sound in the surrounds and spiking the meters. “You’ve got your parabs wide open, and suddenly the PA is all over everything before I have a chance to pull back the faders. As a result, I tend to keep those channels more limited and compressed than I might otherwise, in order to catch those moments.”

But the biggest problems are in NBA arenas, where more microphones are picking up amplified sound that’s not only much louder than even a few years ago but also contains far more low-frequency information, which can overstimulate the subwoofer channels of home 5.1 surround systems. Compounding the problem is that, at the behest of team owners, some NBA arenas have deployed their own microphones to pick up and put through the PA the same kinds of sound effects that broadcast audio looks for, placed in similar locations, such as above the stands and on the backboards. These live-sound effects can wind up affecting the on-air effects mix balance or cause artifacts like comb filtering.

According to several sources, within the past couple of years, the NBA conducted a series of courtside sound-pressure level (SPL) measurements aimed at determining at which points in the game the interior sound levels were the loudest, but the results have not been published. The NBA would not comment on the program.

Adler says that the distributed sound systems that grew in popularity in the past 10 or so years to bring sound closer to the fans in the stands now also bring PA sound closer to announce booths, where headsets and handheld mics pick it up and it can compete with commentary. He says, in some cases, he’s had to ask the venue to turn off the PA zones closest to the booths.

“The biggest problem is when it gets into the commentary mics,” he adds. “When that happens, it’s not only bad for the on-air mix but for the camera operators and production folks who rely on the announcers [for cues].”

Answers in Technology
Even these problems, however, may find technological solutions. Joe Rimstidt, systems design engineer for Yamaha’s NEXO line of speakers, points to the Rupert Neve Designs Portico 5045 Primary Source Enhancer that his company distributes. The two-channel analog unit, which enables up to 16 dB of additional gain before feedback and reduces background, thus enhancing the intended main audio source, has been installed for use with referee microphones in the Alamo Dome, Notre Dame, Northwestern, Green Bay Lambeau Field, Cowboy Stadium, Reliant Field in Houston, University of Phoenix Stadium, and the Rose Bowl.

“Sound systems are getting better all the time,” says Rimstidt, citing greater output, lighter-weight enclosures, higher efficiencies, more articulation, and better phase response as the kinds of improvements that systems in general are achieving. “Better directivity is among them, and that will help keep some of the live sound out of the broadcast.”

Nonetheless, the problem underscores how the trajectories of both live venue sound and broadcast sound over the past decade, which have been substantially amped up to enhance the fan experience, have also been on something of a collision course. There’s no doubt that both broadcast audio and venue live sound have accomplished their respective missions. Now they may have to find out how to better coexist.