Tech Focus: Intercoms, Part 1 — Finding Alternative Channels

A year ago, the imminent loss of RF spectrum was the main issue confronting intercom manufacturers and users. A year on, spectrum reallocation remains a concern in wireless communications, but the growing availability of VoIP-based signal transport for communications has taken some of the edge off the issue.

“It makes sense to continue pursuing [the IP] approach for audio, and it’s gaining traction,” says Robert Pennington, sales manager for Riedel Communications’ East Coast broadcast market. “It’s easier to use for signal transport on a number of different levels, such as being able to port intercoms over to digital radios. We’ve also introduced apps that allow intercoms to be ported over iPhones and build virtual panels for tablets and laptops. Going with IP really opens up a lot of doors.”

He says that the bring-your-own-device phenomenon, which has deeply penetrated many tech fields, is beginning to do the same with intercom audio and, in the process, is driving the category toward more use of networked audio. However, the introduction of so many consumer devices into the intercom signal chain has underscored the need for — and current lack of — widely implemented standards for their integration. Several manufacturers, for instance, are looking at making their systems compliant with the AES67 protocol.

Commercial networking solutions are also making inroads. Both Studio Technologies and RTS, for example, have signed on with Audinate’s Dante networking system.

Studio Technologies’ Model 45DR Dante-to-two-channel partyline intercom interface is designed for applications that use two-channel analog partyline intercom circuits, and its Model 45DC is designed for applications using one or two single-channel analog partyline intercom circuits. Both interface partyline circuits into standard Ethernet networks.

The ADAM intercom system from RTS, which along with sister company Telex is considered the market-share leader in intercoms for U.S. remote trucks, can be interfaced with an audio network via its RVON-I/O, providing a single RJ45 Ethernet connection for use with a 10Base-T or 100Base-TX network to achieve eight-channel I/O and offering configurable network and bandwidth parameters that can be tailored to individual network functions.

In fact, the proliferation of networking protocols offers opportunities for both diversity and confusion. According to Pennington, compatibility with both AES67 and Ravenna will arrive for Riedel’s products later this year, but the company will continue to support its own networking system, RockNet, which was deployed during last year’s World Cup broadcasts. “The real goal is to remain as standards-agnostic as possible,” he says.

Not All There Yet
Not everyone is enamored of IP-based networking as the main conduit for intercom audio. Vinnie Macri, product marketing manager, Clear-Com, says networked audio is fine for long hauls and, in particular, is suited for the accelerating trend of mixing and even directing sports shows from distant central locations, an approach increasingly implemented by both ESPN and Turner Sports from their respective operational centers in Bristol, CT, and Atlanta. But, says Macri, for getting from the track, the field, the stadium, or the rink to the truck, fiber cabling is more than sufficient, offering reliability that a LAN might not under mission-critical circumstances.

“If I’m doing a press conference in the Hilton, do I need to put all the microphones and the audio console on a network?” he asks. “What do I gain in that short a space, and what are the risks I incur on an IP system? If I want to send it to Chicago, then a network is a great idea. But, if it’s only going 50 yards, I’d stick with cable.”

Macri believes that IP-based distribution solutions will coexist with IP-based ones. Clear-Com recently introduced several products intended to be used on LANs, such as its LQ-Series compact interface boxes that can connect two-wire and four-wire audio and call signaling over IP networks. But, he adds, although IP transport can manage audio easily using developing standards like AES67, control data will be harder to make fully compatible across multiple manufacturers’ platforms.

George Hoover, CTO at truck builder NEP, sees IP intercom-signal transport in remote applications coming but not necessarily quickly or comprehensively, with wired MADI remaining a reliable mode for some time: as with consoles and microphones, there’s little to compel change on the part of the broadcasters that order the trucks and specify their main platforms, and largely freelance-based staffs will still look for familiar products on high-pressure projects. What Hoover does expect to prompt the shift to IP distribution in the long run is how open standards for networked audio make different brands and models of intercoms more easily interoperable, letting projects mix and match trucks. “Once an RTS can talk to a Riedel,” he says, “it makes it a lot easier.”

The move to BYOD, networked audio, and app-based intercoms will also bring more-sophisticated communications capabilities to the growing base of midsize and small remote vehicles increasingly used as infrastructure for regional sports networks, a market that all manufacturers are eyeing.

“There’s a much broader base of sports-broadcasting users now,” says Riedel’s Pennington. “Apps and iPads are going to let us reach price points that may have kept some people out of the market before.”

Click here for Tech Foccus: Intercoms, Part 2 — What’s on the Market