Last April, the Billboard Latin Music Awards celebrated its 15th anniversary with a big show at the Miami Arena. Produced and broadcast live for the first time on Telemundo, the event is Latin music's largest awards show, and recognizes artists on the basis of radio and retail chart performance. Performers included Arturo Sandoval, Gloria Estefan, Luis Fonsi, and Alicia Keys, among others.

From a technical point of view, this year's event was also noteworthy for making extensive use of wireless audio technology, both inside and outside the venue. The show included wireless systems from different manufacturers, including Audio-Technica and Shure, but Sennheiser systems were used most extensively. All of the Sennheiser tools were provided and operated by Professional Wireless Systems, a Masque Sound company out of Orlando, Fla.

Working Wireless

Tallying the RFs used inside the venue, the additional systems used outside for the red-carpet portion of the event, plus those used by the ENG crew outside, Professional Wireless president James Stoffo estimates that around 150 wireless mics were used at the show site.

Onstage, a live performance by Alicia Keys made use of Sennheiser's new RF Evolution G2 Series. Keys sang and played piano on “If I Ain't Got You,” a duet with Cuban-American jazz trumpeter Arturo Sandoval.

“She was using a Sennheiser G2 wireless monitor and the new SKM 935 transmitter with the MMD 935 dynamic capsule,” Stoffo says. “The G2 gear easily cut through the forest of RF.”

It didn't even require Stoffo's purpose-designed helical antenna system, he says. “We just had her G2 receiver backstage with the Sennheiser paddles, and the signal was solid the whole time. It was an interesting marriage of old and new technologies. The Evolution systems with the high-end Sennheiser equipment both performed flawlessly.”

Introduced at the beginning of this year, the Sennheiser G2 series features smaller bodypacks, expanded receivers, 1,440 available channels (due to a broader switching bandwidth of 36MHz), free channel search scan, and true diversity receivers and compatibility with earlier E series models.

Sennheiser's high-end EM 1046 multi-channel receiver systems were also used inside and outside the arena, along with lavalier microphones, SK 50 bodypack transmitters, and SKM 5000 series handhelds. Each receiver module of the 1046 can be tuned to one of 4,800 different frequencies, ensuring solid RF performance during the event despite the large number of devices in use.

Bandwidth challenges

Stoffo spent several years working at Vega Wireless in Los Angeles before starting Professional Wireless Systems in the early 1990s. He is well versed in the art of pulling clear bandwidth out of the cluttered airwaves, and his team again faced this challenge at the Billboard event.

“We've fallen into doing high-end, live broadcast wireless operations, whether it requires mics, coms, in-ear systems, or IFBs,” he says. “One of the main challenges we encounter is that with digital TV (taking up bandwidth normally used in wireless applications) it's kind of tough to find clean, uncongested areas.”

While Stoffo does use web resources to isolate problem areas for RF, he says he does that primarily when shipping gear. “But when we get onsite, we have spectrum analyzers, radio scanners, and intermodulation software to determine problem areas,” he adds. “Because once you get on site, there may be things that the web database doesn't know about.

“There's a ton of illegal stuff out there. There's always low-powered stations that are shifting around, and there's harmonics,” Stoffo continues. “I just did a sweep in Jacksonville for the (upcoming 2005) Super Bowl earlier this year. The stadium is right next to two huge RF towers. When you're that close to an FM transmitter, you're going to get spurs, harmonics, and intermods — very nasty. So we usually show up with a spectrum analyzer and the tools to coordinate realtime.”

In addition to these precautions, Professional Wireless Systems also custom designs and builds all of its own helical antennae, as well as its own splitters, combiners for in-ear monitor transmitters, and pretty much any outboard accessory gear.

Of course, even with proper planning and isolation of frequency bands, unavoidable problems are occasionally encountered. Before each event, Stoffo selects some back-up frequencies and makes sure they're clean, so that if the signals have to change during show, he'll already have a dozen places he can switch them to. Even so, Stoffo says he has to keep monitoring systems whenever he has an opportunity. For instance, as soon as the Billboard event would go to a commercial, he would kill the transmitter and look at the receiver. During a two-hour show, Stoffo says he may have to change frequencies a half-dozen times.

The show must go on

With so much competition for bandwidth, even increased receiver transmitter sensitivity and stability won't make much of a difference. This issue can make or break a show in short order, Stoffo says.

“That's why the producers of the Latin Billboard Awards told me ‘You are the frequency coordinator. You have complete authority to shut people down,’ ” he says. “Typically, on a show like this, it's the run-and-gun ENGs that will come in with 20 to 30 RF systems that you never anticipated. You've got to keep a watch on that, and be authorized to shut them down if they step on you.”

With so many potential problems, bringing versatile technology to the event is crucial. Stoffo says the Sennheiser RF system allowed the team to re-tune onsite and have the tools to reprogram across any bands — from 500 to 800MHz.

“Everybody else's equipment stays within a 24MHz band, and that's what you get. And that band may not work very well. You need to be able to shift things around a little, and it's fairly easy to do with Sennheiser.”

Inside and out at the Billboard event, Stoffo used the Sennheiser/Neumann hybrid RF handheld mic, which combines a 5000 Series wireless transmitter with the Neumann/Sennheiser KK 105 S capsule. The mics were used for the show's two hosts, Mauricio Islas and Candela Ferro, and for numerous live performers.

For those just getting started doing wireless work, Stoffo recommends focusing on frequency coordination.

“The reason that's so hard is that we can't see, hear, or smell RF. So your first indication that there's a problem is when it hits your mic: you get a loud noise burst through the system, and everybody yells at you. Monitor RF in advance and coordinate around it — whether you use a list that you pull off a server somewhere, or you bring an expensive spectrum analyzer. Basically, the next few years will present greater changes to the RF spectrum than any other time in history. So it's really important to pay attention to frequency coordination now.”

Alex Artaud pens SRO's audio column and is a musician, engineer, and writer based in Oakland, Calif.