Audio Networking Makes Deeper Inroads Into The Plant

By: Dan Daley, Audio Editor, Sports Video Group

Digital audio networking has dominated the conversation in pro audio for the last three years and with good reason: the transition to a streaming environment for signal transport is the biggest shift in the industry since the changeover to digital from analog. Sports broadcasting is already engaging in networked audio — it was present at the recent Olympics and World Cup productions that saw much of the switching and mixing of audio from venues done back at networks’ plants, and comms and commentary systems are embracing the idea of packetized audio because it brings with it so many collateral benefits, such as automated end-point discovery and naming.

However, bringing sports broadcast audio fully into the networked environment is going considerably slower. The broadcast culture tends to move inherently and understandably cautiously, considering the stakes. Broadcast sports has often been the tip of the spear when it comes to new technologies, such as surround sound over the air, but even that was essentially using existing technologies and formats in different ways. Moving to audio over IP (AoIP) is a paradigmatical shift. It’s also one that appears more inevitable every day.

“In a way it’s already here,” observes Roger Charlesworth, executive director of the DTV Audio Group and a broadcast-audio consultant to sports networks including Fox Sports, noting ongoing implementation of some aspect of networked audio, such as NBCs use of Ravenna and other networking platforms at the Olympics and World Cup. Charlesworth says networked audio’s usefulness is undeniable.

“It is going to be transformative because [comms, IFB and microphone sources] can be merged in the routing cloud instead of operating as separate systems,” he explains. “This will facilitate virtualization of production infrastructure, automatic of setup and routing, and more. A big driver for this will be ‘in-sourcing’ of production assets back to the network plant, such as ESPN’s Production Integration Initiative,” a reference to moving mixing and other functions once routinely done on site back to the main plant.” In fact, Charlesworth adds, routing audio signals alone isn’t networked audio biggest benefit. “That will be the ability to move control data and other metadata around with the audio,” he says.

It Depends

Not so fast, say others. “It depends on who you talk to,” comments Rod Allen, senior project manager at Bexel, a leading provider of broadcast services and video equipment rentals. “We’ve seen MADI really take hold in the last three to four years,” as a mode of audio transport, one that had been available for two decades before the broadcast industry embraced it widely. “MADI gave us compelling reasons to use it, such as sixty-four channels in each direction. We need to see the same compelling reasons to move in large scale to networking.”

Allen’s not saying those reasons don’t exist, but he does feel that the industry isn’t yet widely comfortable with putting broadcast audio onto a network. The push, he feels, will have to come from the major networks. “We’re waiting for a Fox or an ESPN to tell us they want to use something other than MADI,” he says. “So far, we’re getting some requests here and there, but not that strong push.”

Beyond the signal transport efficiencies that networking proponents emphasize, there are also economic and logistical ones. Phil Wagner, president of Focusrite Novation, whose RedNet modular Ethernet-networked audio interfaces use Dante as their network protocol, points out how being able to move 500 channels of audio between two points along a single fiber-optic cable can significantly reduce a truck’s weight by eliminating large amounts of copper cabling. “When you save weight, you’re saving money,” he states. “The efficiency of high-density Dante signals on standard networking infrastructure cannot be overlooked for new truck builds.” Wagner also noted that a new RedNet MP8R eight-channel mic-pre and D64R – MADI bridge have been designed for broadcasting requirements with redundant power supplies and Dante networking. Wagner strongly believes that the transition to a networked environment will be as momentous a shift as the transition from analog to digital was. But, he acknowledges, that shift is up against a well-entrenched culture in broadcast.

2015 Turning Point?

Audinate, which markets the Dante networking platform, says 2015 will be a pivotal year for the market share-leading system, which earlier this year crossed the 200-licensee threshold. The company announced in early April that its long-promised support for AES67, the interoperability protocol published in 2013, will initially be made available in a firmware update for the Dante Brooklyn II card, which will be released to Audinate OEM partners within 30 days of the announcement, for integration and testing into their products. Kieran Walsh, Audinate’s London-based director of marketing, says it’s a move that will make audio networking in general more attractive to a greater number of broadcasters.

“The use case is clear,” he states. “MADI is great for point to point for multiple channels but it’s not bandwidth efficient.” He cites Dante’s use of metadata and other capabilities as benefits that will become clearer once broadcasters feel more comfortable with the open-source AES67 aspect integrated into Dante, and hinting at “major deployments” in the U.S. broadcast sector this year.

Marty Sacks, vice president of the Telos Alliance and a spokesperson for the Media Networking Alliance, the trade organization promoting use of the AES protocol, says networking offers broadcasters reduced costs and more efficiency, and that those will overcome innate reluctance to change. “Broadcast tends to have a lot of islands within it — intercoms, audio routers — these are all islands unto themselves,” he explains. “Once everything is on the same network, the efficiencies increase dramatically; once it’s all on a single Cat-5 cable instead of hundreds of copper wires, costs go down.” Sacks says that AES67 will encourage more uptake of networked audio by increasing interoperability between devices from different manufacturers.

There is broad consensus that broadcast audio production will move onto networks at some point. Where there’s less agreement is when a tipping point may be reached and what that landscape will look like at that point, in terms of which systems and platforms will be dominant. But it appears certain that AV is heading into IT territory.