Tech Focus: Networked Audio, Part 1 — Where Broadcast Sound Is Now
IP came on fast, if a bit unevenly, and it’s transformative
Broadcast-audio veterans will recall the tectonic shift that was the migration from analog to digital, a move that spanned the better part of three decades, from various PCM formats on tape to the complete virtualization of audio on hard drives. By comparison, the shift to IP-based signal transport has been incredibly rapid, taking less than a decade to become ubiquitous at the upper levels of audio production, including broadcast.
There are a number of reasons for that. A major one is that an entire IP infrastructure was already in place in the IT systems used for data-based applications from HR to sales, along with the skill sets to utilize it. That existing IP infrastructure was applied initially to signal control, but audio followed quickly thereafter.
Don Bird, VP, business development, Lawo, notes that broadcast has been able to “leverage existing off-the-shelf solutions that have undergone extensive testing and standardization for the computer industry.” But, he adds, “business decisions have to be made first and can often present challenges regarding project scope and timelines. And, as an industry, we are still working through our own issues of standardization around open protocols that will foster improved connectivity and control across the network.”
Kieran Walsh, director, application engineering, EMEA, Audinate, parent company of the Dante IP format, agrees that the penetration of audio over IP into broadcast has been rapid, but, he adds, it has often been uneven, largely because of the infrastructure of each company and each aspect affected: for instance, IP uptake is faster by plant studios than by remote production.
“It’s really moving on a case-by-case basis, depending upon the infrastructure and skills of each broadcaster,” he says. “It’s not surprising that OB production will take longer to integrate IP. At 64 channels, MADI is a very good fit; as a result, MADI will remain in place for some time to come.”
Although 30-year-old Will Hoult, UK-based senior product manager for Focusrite’s RedNet network interface line, wasn’t around for professional audio’s sometimes traumatic transition from analog to digital, he’s aware of its magnitude.
“Just switching from MADI or analog point-to-point to networked IP, the change of platforms and paradigms carries with it huge inherent risk,” he acknowledges. “The deployments we’ve seen in broadcast are generally more cautious, with new plant facilities quickly embracing IP while existing studios integrate it more slowly,” reflecting the criticality of live broadcasts like sports.
Hoult also notes that uptake of IP has been faster in the U.S. than in Europe, where state-backed broadcasters tend to make transitions in the background, often working closely with product developers, and then roll out the technology consistently throughout their plants. U.S. broadcasters, including the major networks, may push unilaterally for the transition to happen faster once their accountants see the cost savings that IP brings, resulting in uneven uptake across the industry.
“Point-to-point brings with it a higher total cost of ownership, due to the hidden costs of installing and maintaining a [cable-based] infrastructure,” he says. “Networked audio, on the other hand, leverages IT infrastructure and expertise that’s usually already in place and costs less to maintain. Different companies come to that realization at different times.”
Plugfests Show More Work Is Needed
Henry Goodman, director, product development, Calrec, attributes the rapid uptake of IP to the relatively fast development of standards around it. “With AES67 embedded in ST 2110, that approach is pretty much written in stone now for moving audio signals from point A to point B,” he says, referencing two key AES and SMPTE standards.
However, he adds, ongoing plugfests — small conferences designed to test interoperability of IP devices — continue to reveal issues in interoperability. The individual programming that each device can receive at these types of events also underscores the fact that more work remains before all IP devices can function as automatically as necessary in a live-broadcast environment.
According to Goodman, remote-production trucks offer perhaps the best environment for realizing the benefits of a full IP ecosystem. The truck is a standalone environment; in a broadcast plant, individual studios are converted to IP sequentially, creating a hybrid environment for an extended period. Longer term, he predicts, even consoles themselves will deploy switch-based routing internally, which would complete the transition from linear-signal to data-packet transport.
The Future Is Here
Despite’s IP’s rapid inroads, Bird agrees that broadcast will likely be a hybrid environment for the near term. “Hybrid infrastructures will still be the order of the day for many. Standards continue to be refined, yes, but the good news is that there remains a strong emphasis and focus on those standards being non-proprietary and enabling the maximum amount of flexibility in the design and operation of IP-based production workflows.”
Going forward, say all, there’s no going back: IP is the infrastructure of the future and for much of the present. Walsh points out that the most recent standards applicable to AoIP, most notably the SMPTE ST 2110 suite, incorporate more-practical elements along with the science. “It’s gratifying that we’re now getting more pragmatic proposals for these timing standards based on experience and less and less from the ivory tower.”
Bird cautions that the future will be about integrating audio with video and control data on an IP infrastructure. “The remaining challenges relative to audio lie around realization of an IP ecosystem that includes video and data as well,” he explains. “These are not audio-centric issues but are more about how all of the elements, video, audio, data, network infrastructure, and control are orchestrated and brought onto a homogenized platform that can be efficiently managed and utilized.”
Click here for Tech Focus: Networked Audio, Part 2 —Where Live Sound Is Now