Tech Focus: Networked Audio, Part 2 —Where Live Sound Is Now
Sports venues’ sound systems are getting smarter, benefiting from IP
Live sound in the venue is undergoing the same tectonic transition that broadcast audio is experiencing: the migration from analog and digital point-to-point transmission to being fully hosted on IP-based networks. Venue sound systems have inherent limitations when it comes to this paradigm shift — signals generally go back to analog for their “last mile,” from amplifiers to speakers (although active/powered speaker systems can have a very short last mile) — but, from source through DSP processing and amplification, most new sound systems and major system upgrades feature signal transport over IP.
Click here for Tech Focus: Networked Audio, Part 1 — Where Broadcast Sound Is Now
Ben Cating, senior consultant/VP at A/V consultancy Idibri, which has worked on such venues as Angels Stadium and U.S. Bank Stadium, says most new sports-venue sound systems encompass some degree of dedicated audio networking. The transition happened quickly, he adds, propelled by manufacturers’ integration of various networking protocols. These included AES67 and AVB standards when they became available, but, by far, Dante compatibility spurred the effort.
“It happened very fast, and Dante drove a lot of that, though AES67 and AVB also pushed it along,” he says, noting “alternatives, including QSC’s Q-SYS network, that are widely used. We’re also still designing in analog backup to major parts of systems. That will also be around for a while.”
Paul Murdick, GM, audio/video, integrator TSI Global, whose sound systems are in Busch Stadium, Citi Field, the Edward Jones Dome, and Target Field, sees IP as a de facto standard for venue sound. However, it’s up to individual venue owners and managers to determine how deeply those systems go into networked domains.
“Is it going to ride on a separate network, or will it be part of the existing VLAN inside the venue?” he asks. “Those are the kinds of things that are being decided now. The idea of using a network at all is less of a question: a network will be involved to some extent. When networks were operating at 100 Base-T, sound needed to have its own network, which could add to the cost of the overall system. But now that we’re routinely at 10 GB and higher levels of broadband, existing network infrastructures can have enough bandwidth on them to allow audio to share them.”
Networked audio for live sound in venues is adding flexibility to system design and implementation. For instance, as venues strive to make the experience consistent between the bowl and the concourses around it, point-source and line-array systems covering the playing field can easily be integrated with distributed systems better suited for back-of-house coverage.
Networked systems offer certain efficiencies, such as lower maintenance costs, remote access for monitoring, repairs with software able to flag potential failure points, more-precise zoning allowing better coverage, and elimination of analog-cabled problems, such as ground loops and other artifacts.
However, Murdick points out, the IT skills that broadcasters are leveraging for audio-over-IP applications aren’t completely fungible when it comes to live sound, which has aural nuances that cannot always be precisely quantified.
“You cannot replace human hearing and what a trained and experienced ear can discern, when it comes to audio quality and things like artifacts,” he stresses. “You can turn a sound person into an IT technician with training, but doing the reverse is a lot harder. As IP gets deeper into live sound, it argues for a hybrid set of skills.”
Kieran Walsh, director, application engineering, EMEA, Audinate, parent company of the Dante IP format, believes that, although the incremental steps that have led to the current level of AoIP in sound have been challenging, IP clearly washed over the industry remarkably quickly.
“When you’re dealing with bringing it on in the moment, on a day-to-day basis, you really feel the pain,” he says. “But, looking back, it was certainly less so than going from analog to digital.”