Live Broadcast of Annual Festival Parade Enjoys Flawless RF Audio in Downtown Chicago

The live HD broadcast of Chicago’s 2011 Magnificent Mile Lights Festival by WLS-TV, an ABC-owned TV station, is a challenging event, requiring extensive use of wireless microphones and intercom systems in an RF-intensive outdoor environment. Performers included Grammy-winning sister duo Mary Mary. Parade grand marshal Mickey Mouse was on hand to illuminate more than one million lights on 200 trees lining Michigan Avenue, officially kicking off Chicago’s holiday season. This perennially difficult assignment became much easier in 2011 with the use of a new and unique wireless microphone system: Shure Axient with frequency diversity.

WLS enlisted the aid of On Stage Audio (OSA) in suburban Wood Dale to supply the needed audio equipment. OSA senior staff engineer Pete Wiejaczka, along with Kelly Epperson of Easy Live Audio, offered the station the opportunity to employ the new Axient system. Axient is Shure’s state-of-the-art wireless network management system, designed to handle the most crowded RF conditions with a range of advanced features that include extremely tight RF filtering combined with spectrum management, frequency diversity, and remote transmitter control via wireless data communications.

The parade route is on Michigan Avenue in the heart of downtown Chicago, an RF-rich environment made even more complex by event logistics. ABC 7’s temporary broadcast site included a “backstage” tech area and nearby dais for three broadcast anchors. It also required wireless signals for street reporter Val Warner on the parade route and the nearby performance stage. The location provided additional wireless challenges by being within line of sight of several nearby DTV antennas and adjacent to a competitor’s broadcast studio.

After the capabilities of Axient were explained to them, WLS and audio engineers Lou Sabatini and Mike Cunningham could not pass up using the new Shure system. “Once we saw what Axient can do, we knew it was perfect for this event,” explained Cunningham.

As a result, eight channels of Axient were employed, including a handheld and bodypack system for Warner, and a pair of handheld mics for Mary Mary. The results did not disappoint.

Axient constantly monitors the full RF spectrum to detect potential interference. In addition, its frequency diversity feature enables a second, independent frequency from the transmitter. When interference is detected, the system can seamlessly switch to a clear backup frequency, enabling mission-critical transmitters to survive even the most challenging conditions without a glitch.

“We had an absolutely flawless wireless system throughout the broadcast,” reports Sabatini, who handled the broadcast mix. “We also got to see first-hand how Axient can detect and prevent a problem before it happens.”

During rehearsal, the system detected interference on one of the anchors’ system. “The display on the receiver turned red to show us the problem,” reports Cunningham, who was responsible for frequency coordination. “It turned out to be interference from an unplanned in-ear system. Axient switched the transmitter and receiver to a safe frequency. That would have been a major panic situation, but Axient handled it seamlessly – detecting the problem, alerting us, and having a safe channel ready to go.”

The other demonstration of Axient’s capabilities involved reporter Val Warner. Her handheld Axient was working fine in low power mode as the broadcast began, but as the parade route filled with the estimated 250,000 attendees, the system detected a reduction in signal strength. “She was about three-quarters of a block away when the receiver went red,” reports OSA’s Pete Wiejaczka. “I was able to push data to that handheld to switch it to high power mode and right away, we had a solid RF signal again. It was great that, with the tools Axient provides, we were able to deliver a seamless performance for our client.”

Shure Axient wasn’t the only piece of advanced wireless technology contributing to the success of the broadcast. For PL communications, Clear-Com provided four channels, 10 users, of Tempest900 wireless intercom for parade coordination. The all-digital Tempest system operates in the 900 MHz frequency band, and its patented spread spectrum frequency-hopping RF architecture assured excellent range, coverage, and no interference from other RF sources.

“This was the first time Tempest was used in Chicago,” reports Lou Sabatini. “We had crystal-clear communications throughout the broadcast, which was critical for those coordinating the flow of the parade.”

Finally, to get broadcast audio to the bleachers located across Michigan Avenue from the broadcast position, Wiejaczka employed the new Shure PSM 1000 personal monitoring system in its point-to-point mode, sending full-range audio to the PA system with no discernible latency or quality loss. “It’s really a great system,” Wiejaczka notes. “The sound quality is excellent, and the PSM 1000’s point-to-point mode allows me to use a Shure UHF-R receiver, which meant I had real balanced XLR outputs instead of just the mini headphone jack that’s on an in-ear bodypack. It’s a great solution anytime you can’t run cable to the PA system.”

Video from the November 19 live broadcast of the 2011 Magnificent Mile Lights Festival is available on the station’s website, and will be rebroadcast by ABC7 Chicago and in 72 markets nationwide via syndication throughout the holiday season.