Audio: Gaining Ground and Looking Up

Lawo Remote Production Kit

Change is in the air at NAB Show. Next Gen TV, also known as ATSC 3.0 continues to pick up momentum; object-based audio is gaining ground; IP-based workflows are starting to coalesce around a standard; and console-makers are offering new live production workflows.

Meanwhile, for wireless audio equipment operators, things are looking up — up the frequency spectrum, that is.

Calrec RP1

Just ahead of the show, the Advanced Television Systems Committee published A/342 Part 2 and Part 3. The publications respectively describe Dolby’s AC-4 and Fraunhofer’s MPEG-H audio codecs, which support immersive audio and personalization in the ATSC 3.0 suite of Next Gen TV broadcast standards.

Broadcasters are already on-air with immersive audio, said Roger Charlesworth, executive director of the DTV Audio Group. “MVPDs like Comcast and DirecTV are delivering Dolby Atmos to the home,” he said. Cinema-derived Dolby Atmos content is available for home consumption and now Amazon, Netflix, HBO, Starz and others are commissioning shows to be mixed in Atmos, he added.

Delivery is currently via Dolby DD+ JOC (E-AC-3 with Joint Object Coding). “But I think we’re going to start to see people switching over to AC-4,” said Charlesworth. Sports, particularly the U.K.’s Premier League soccer, and live music concerts are also driving Atmos adoption, he said.

Shure ULX-D

SMPTE’s set of IP media networking standards, ST-2110, has built momentum for the AES67 audio-over-IP interoperability standard. Video vendors have rallied around 2110, which describes a specific implementation of AES67 as the transport for the separate audio essence.

“At the Video Services Forum Interop in Houston, 30-some-odd companies tested equipment including AES67,” he said. “We now have what will be a widely supported standard.”

With the forward auction phase of the FCC’s Incentive Auction over, wireless equipment operators have clarity on the future RF landscape, said Charlesworth. “As we suspected, we’ve lost all the 600 MHz band down to Channel 37. That’s going to make wireless operation in the UHF band very problematical in some areas.”

Wheatstone At-Home

The DTV Audio Group and its members — manufacturers, consultants and heads of audio from TV networks — sought alternative spectrum from the FCC during the lead up to the auction. The FCC’s Report and Order opened access to significantly more spectrum in the 900 MHz band; access to a portion of the 1435–1525 MHz band at specified times and places, subject to coordination requirements that protect critical aeronautical mobile telemetry; and access to portions of the 6875–7125 MHz band.

“In metropolitan areas, 900 MHz is widely used already. For ̔The Today Show,̕ for instance, when they are on Rockefeller Plaza, all the mics and IFBs are in 900 MHz,” said Charlesworth. He predicts that some manufacturers may unveil 1.4 GHz equipment at NAB Show.

Some manufacturers are showing higher-density UHF solutions. Shure and Zaxcom, as examples, offer high-density solutions that fit 50 or 60 channels into a 6 MHz chunk. “But if you need a couple hundred or a thousand channels, like the Super Bowl, that doesn’t help,” said Charlesworth. “And if you’re in New York or Los Angeles there just isn’t going to be enough UHF.”

Manufacturers saw the present scarcity of RF bandwidth coming before the transition from analog broadcast to DTV. Audio-Technica responded with a new company, Alteros, dedicated to providing solutions that address the evolving RF landscape.

Building on A-T’s experience with digital Ultrawide Band technology operating above 6 GHz, Alteros is launching its GTX Series wireless mic system at NAB Show. The system, which requires no frequency coordination, supports 24 body-pack transmitters with a network of up to 32 antennas and can be deployed in a few hours, according to the manufacturer.

The widespread adoption of AoIP networking transports by broadcast audio mixing console manufacturers has enabled mixing, routing and processing resources to be distributed across a network, including over significant geographical distances. At-home production, pioneered at events such as the Olympic Games and by Europe’s LiveIP project, where sources at an event are transported over IP to the plant for mixing, is now poised for wider adoption in the United States.

Using IP interface, routing and DSP products such as Wheatstone’s selection of Blades, Calrec’s RP1 remote production engine or Lawo’s mcÇ MicroCore, sources in the field can be mixed for air at the distant home studio as if they were coming from the studio next door. The ability to cover more events for less money? That’s the sort of change broadcasters can believe in.