Tech Focus, Part 1: Surround Microphones Inch Closer to Primetime

By: Dan Daley, Audio Editor, Sports Video Group

The dedicated surround microphone occupies a unique niche in pro audio in general and sports broadcasting in particular: somewhat exotic, technically sophisticated, relatively expensive, alluringly complex, yet seductively suggesting a simple solution at a time when 5.1 surround or more has become ubiquitous. Still, market penetration, particularly in broadcast, has been relatively slight. The high cost of surround microphones has certainly been a major factor, as has the architectural diversity of many sports venues, which makes their predictable placement difficult.

However, the increasing ubiquity of surround sound on television means that these rarified transducers have been creeping into the inventory more often.

For instance, the DPA 5100 and Holophone H2Pro-5.1 surround microphones have been on the menu at CP Communications for 18 and six months, respectively, and demand for them has been picking up, says company President Michael Mason, although it’s not the networks that are driving it.

“It’s still very much A1-driven,” he explains, noting that some entrepreneurial A1s will either rent the single-point surround mics and then sublet them as part of their compensation package or just buy them outright and do the same. However, Mason adds, most of the time A1s still opt for a surround field created by using multiple single-point mono and stereo shotgun mics. “It also varies from sport to sport, too.”

Greater Variety
Cost remains an overriding factor. DPA and Holophone microphones can approach unit prices of $5,000 or more, and SoundField’s DSF-B Digital Broadcast Package ranges into the low five figures, including its processor. However, several companies have created simpler and lower-priced surround-mic products, such as Holophone’s Sports Mic and HD3, which sell for $1,000 and $2,000, respectively, a fraction of the $6,000 price of its H2 Pro flagship model.

Other companies are expanding the market with related technologies. This year, Sennheiser introduced its Esfera kit, which consists of an SPM 8000 two-channel microphone (a version of its MKH8040) and an SPB 8000 processing unit. The processing unit uses an algorithm matched to the microphones to generate a 5.1-surround signal at sampling rates of up to 96 kHz. It features four selectable presets: settings for the gain of the individual channels, front and surround focus, surround delay, rotation, filters and cutoff frequencies, compressor, makeup gain, output gain, limiter, and windshield compensation. The system is priced at $9,999.95.

Dave Missall, Sennheiser’s manager of technical services and market development in the U.S., acknowledges that the Esfera system, which made its broadcast debut at the World Cup in Brazil, generates a surround image via algorithmically manipulated phase and gain from a pair of microphones in an X-Y configuration, essentially upmixing a two-channel signal, instead of using multiple dedicated microphone elements. It’s also more expensive than some dedicated multi-element surround microphones, but, Missall says, it results in higher SPL and a wider frequency response, particularly in lower frequencies.

“We’ve done tests with NASCAR races, and it works very well,” he says. “Facing it towards the grandstand, you can hear a car approaching from the right rear channel, [traversing] the surround field, and then leaving from the left rear [channel].” Missal says other tests have been conducted by TNT with the Atlanta Braves.

However, Tom Sahara, VP, operations and technology, Turner Sports, discussing audio for the new NBA season, says TNT continues to evaluate dedicated surround microphone systems but none have met their expectations yet. “We’re continuing to experiment,” he adds.

Predictable Venues Help Proliferation
In Europe, particularly in the UK, it’s a very different story, and recently named NBC Sports Director of Sound Design Karl Malone is well-positioned to observe it: he began his career as an A1 in the UK. Given the overwhelming dominance of a single sport there (soccer, or football, depending on which side of the pond you live on), the limited number of national broadcasters, and the architectural uniformity of its stadiums permanently installed dedicated surround microphones are a good fit, he points out.

“UK stadia generally follow a certain build structure which places camera positions and announcers under an extended roof structure generally in the 130-ft. to 160-ft. height range,” he explains. “The announcer position can either be hanging from that roof closer to the rear stadium wall or extended out as much as 30 ft. [Hanging] a surround-microphone system [there] will give you lots of left-surround/right-surround crowd [sound] behind the microphone.”

By comparison, in the U.S., the variety of major-league sports, the diversity of their venues’ architectural designs, and the scattering of broadcast rights among a half dozen major networks and a growing number of regional sports networks, plus the relative independence of the freelance base of A1s and A2s (versus Europe’s staff-based production teams), work against a uniform approach to capturing surround elements.

As a result, the UK has a burgeoning infrastructure of dedicated installed surround microphones. Malone notes that “a major UK soccer broadcaster” specified that SoundField microphones be permanently installed at every Premier League venue so that they could be immediately accessible to visiting broadcasters.

“They do an extremely good job at providing a phase-coherent and relatively controllable 5.1 image from a single-point system,” he explains. “The wide deployment of the SoundField microphone in the UK gives the mixer and listener a consistent surround-weighted mix from every venue. This is very valuable in keeping things simple and technically reliable.”

Malone acknowledges that U.S. sports-broadcast culture is inherently inhospitable to single-point–surround microphones, citing “the time required to set it, test it, and secure it particularly if the placement is challenging.”

Musing on how that might ever change, he says, “If all NHL, NFL, MLB, NBA stadia were asked to supply permanently rigged/setup surround-microphone systems as part of their contracts with the rightsholding broadcasters, perhaps only then would we get a conversion to a surround-microphone system amongst major sports broadcasters.”

That may be changing. Holophone CEO Jonathan Godfrey is seeing more interest in the dedicated surround microphone at the network level. “3D audio is starting to look like a viable format for the future, especially for sports,” he says, noting multichannel formats from Dolby and the Fraunhofer Institute. “It’s the best way to achieve effective, realistic audio for sports. Also, 3D sound is what will be needed to match increasingly high-resolution television pictures.”

Single-point surround microphones will remain a niche for some time to come, but what will likely soon change is the size and scope of that niche. With new multichannel formats on the horizon and the need to fill surround channels for a larger array of sports shows, the next year or two could prove to be this category’s chance to shine.