ARC includes software processing algorithms that constantly make intelligent decisions to adjust loudness levels.
Linear Acoustic has been helping broadcasters meet FCC regulations with audio processing and loudness control for the past 15 years. These devices are used extensively across the broadcast community to ensure compliance and avoid costly fines. However, they themselves can be expensive and out of reach for many regions of the world.
At the 2018 IBC Show The Telos Alliance TV Solutions Group will spotlight a new hardware-based DTV stereo-only loudness processor called Linear Acoustic ARC (Automatic Realtime Control) that’s easy to set up, less costly and fully compliant with all global loudness standards and recommendations. The box uses Linear Acoustic’s proprietary APTO adaptive loudness processing to adjust the audio streams—AES, SDI or LiveWire+ AES 67—to fit the user-selectable profile.
The core of ARC is Linear Acoustic’s new APTO software processing algorithms, which analyze in real time the audio streams and make intelligent decisions about loudness. The user tells the box what they want the output to be and APTO adjusts the processing accordingly. [APTO is Latin for “to adapt”]
Jim Kuzman, Senior Content Strategist at The Telos Alliance TV Solutions Group
“In addition to being affordable, ARC works when it needs to work and does not change the content when it does not need to,” said Jim Kuzman, Senior Content Strategist at The Telos Alliance TV Solutions Group. “At the end of the day the user wants quality audio that closely adheres to the original content as it was delivered to the broadcaster. ARC is intelligent and adaptive, so it retains that quality throughout the entire loudness monitoring and correction process.”
It’s designed for price-conscious broadcasters looking to ensure compliance while distributing audio programming as stereo. ARC is packaged in a two program, 2-channel, 1RU frame that features a user-definable loudness target. There’s support for the EBU R128 and ATSC A/85 standards. Plus, real-time processing is still necessary, especially for live broadcasts where audio levels are unpredictable.
“This allows broadcasters to be CALM Act compliant (ATSC A/85 in the U.S.) or conform to whatever the regulations are in their respective countries,” he said. “The real time aspect is very important to our customers. You set a target loudness value (e.g., -23 or -24 for most users), pick a profile and it does the rest.
“What makes ARC unique,” Kuzman said, “is that it’s meant to appeal to a wider audience than some of our other loudness processing products (e.g., the Linear Aero Series, which handles surround sound [5.1 and beyond] audio signals in addition to stereo and coded audio). “We think it will find a home both in America as well as non-U.S. markets, due to its price point and ease of use. It’s a ‘set-and-forget’ box.”
Expected to ship in January 2019 for $3,995, the ARC is now the least expensive hardware box in the Linear Acoustic signal-processing portfolio.
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