SVG Summit: DTV Audio Group Looks at Past, Present, Future
DTVAG Executive Director Roger Charlesworth opened the event with a discussion of how the organization’s previous meeting, in Los Angeles during the AES Show in September, considered how immersive audio, in the form of Dolby’s Atmos format, was beginning to be applied to Hollywood content. A little more than two months later, he was able to tell the 40-plus attendees on Monday, “Now, Atmos for sports is here. The development of new soundbars and headphones make advanced surround sound possible.”
Charlesworth further acknowledged the AES as a location sponsor for the New York event and as a resource as immersive sound is applied to broadcast-sports audio in the future.
Besides shifting to immersive sound, broadcast audio is moving further and faster down the road toward full IP signal transport. Sam Schauland, technical director (Americas) for Lawo, addressed IP connectivity for large-scale events, citing the Rio Olympics, where Lawo deployed 17 of its mc256 consoles and 11 Nova73 compact routing systems for venue audio production, as well as 90 Lawo Commentary Systems (LCU) for remote production for various rightsholders, part of Lawo’s comprehensive VSM approach to broadcast control and monitoring. Technical challenges, such as clocking and troubleshooting in a complex broadcast environment, were examined, along with use of IP-based switching, which Schauland said had never been attempted on such a large scale before. Using VSM, he told the audience, was a substantial step to “getting out of the telco sandbox” and into a true IP-based signal environment.
Focusing on the present, sports-production consultant Jeff Willis reviewed the lengthy narrative that is RF-spectrum reallocation, which began in 2008 with the displacement of broadcasters from the 700 MHz band. Noting that the current reallocation auction for the 600 MHz range has missed expectations for the amount of bandwidth bid on and the amount of money it was expected to fetch from mobile-wireless developers like AT&T and Verizon, he posed the question, “Is the auction failing?” and quickly answered it with a mostly definite “no.”
Noting that 26 billion devices are expected to be connected by 2020, according to a CTA analysis, Willis declared that Stage 4 of the auction process — slated to begin this week — would be successful as an opportunity for those mobile developers to secure at least the minimum spectrum they need to maintain competitiveness with each other. “If you just bid tens of billions of dollars for 20 MHz of spectrum, would you want more or less of unsecured spectrum available to your competition for acquisition?” he asked. (It was a view on which other close observers of the auction at the Summit, including Sennheiser’s Joe Ciaudelli, concurred.)
Loudness, IP Mics, and Remembrance
Focusing on the present, a representative of a major network delivered a summary update on loudness management for streaming media. He reported that the Audio Guidelines for OTT and Video Streaming (AGOTTVS), a group formed within the AES Technical Council to study the issue related to audio-loudness variations, has issued preliminary results. The document, AESTD1005.1.16-09, is available now and includes recommendations for the use of loudness-control metadata and how to handle measurement in the absence of the U.S. -24 LKFS standard. A longer-range goal is to collect data for a wide variety of streaming devices to develop more-specific guideless for that environment.
Looking forward, Ben Cochran, product engineer at Audio-Technica, discussed his company’s development of an IP-connected microphone and its applications. IP-connected microphones, he said, are a key “edge,” or system-periphery, device that will help propel implementation of larger IP networks in broadcast, extending its high data rates and scalability. He used several diagrams to underscore the relative signal-transfer simplicity of IP-connected microphones versus ones using traditional copper connections. As important, he noted, is the fact that IP-connected microphones can include all of their relevant metadata in an automated bitstream, versus the handwritten “scribble strips” used now. He acknowledged security and other broadcaster concerns but pointed out that the incorporation of the AES70 standard, which addresses device control and monitoring, will ultimately help the uptake of IP microphones.
Rob France, senior broadcast marketing manager at Dolby, reported on the limited use of Atmos for the Opening Ceremony of the Rio Olympics, where an Atmos-encoded mix was backhauled via a DolbyDigital Plus (aka DD+ and Enhanced AC-3) compressed bitstream to NBC facilities in New York and to a reception at the Brazilian embassy in Washington. Another demo, this one at the Euro 2016 series, was done for delivery to China’s CCTV. That event also deployed a new Schoeps 3D microphone array using side-address cardioid elements pointing upwards. France said that the overhead channels in Atmos — which largely define immersive broadcast audio — made a huge difference in the broadcast experience.
France also announced at the DTVAG event that the UK’s BT Sport network will deploy Atmos for one Premiere League match per week starting Jan. 31, alongside BT’s 4K production, over 4K IPTV service.
The DTVAG event concluded with a remembrance of the late Bob Dixon, with anecdotes related by close friends and associates. Among them, SVG Chairman Tom Sahara, VP, operations and technology, Turner Sports, reminded the gathering that “[Dixon] changed audio as we know it, especially for live events. Much of what we see today has his fingerprints on [it].”