Latin America. ATSC has completed a major revision of its Emmy® Award-winning A/85 Recommended Practice: Techniques for Establishing and Maintaining Audio Loudness in Digital Television. This is the first comprehensive update to the industry benchmark since 2013.
The revision reflects more than a decade of technological evolution in the production, distribution and delivery of television content, providing broadcasters, equipment manufacturers, content creators and streaming providers with a modern guide to delivering a consistent, high-quality audio experience.
For years, the ATSC A/85 standard has been the industry's authoritative guide for measuring and managing audio loudness on television and has been widely used by broadcasters to comply with the U.S. Commercial Advertising Loudness Mitigation Act (CALM). More recently, the state of California enacted a new law on commercial audio loudness for various streaming media services, requiring practices "consistent with regulations adopted by the FCC pursuant to the CALM Act."
ATSC's new Recommended Practice modernizes the document with numerous technical clarifications and introduces two important new annexes:
A guide to establishing and maintaining a uniform loudness level in multimedia streaming services, using audio codecs with and without metadata.
A new Quick Guide to loudness and Pico Real, designed to simplify deployment for engineers and content providers.
"As audiences increasingly consume content across terrestrial and streaming platforms, maintaining a consistent listening experience has become more important than ever," said Madeleine Noland, President of ATSC. "This update to the A/85 standard provides the industry with practical and up-to-date guidance that reflects current production and distribution workflows, while preserving the high-quality experience that broadcasters have strived to deliver for years."
The revised A/85 Recommended Practice provides recommendations for measurement, monitoring, production, metadata management, dynamic range control, and audio loudness management throughout the entire content creation and distribution chain. By incorporating lessons learned from more than a decade of implementation, as well as addressing emerging broadcast workflows, the document helps ensure consistent audio presentation, regardless of how viewers access content.
This revision represents an important milestone for the broadcast industry, as media organizations continue their transition to hybrid IP-based broadcast and broadband distribution models. Extending loudness guidelines beyond traditional broadcast applications contributes to greater consistency for audiences, while reducing operational complexity for organizations distributing content across multiple platforms.
The revised A/85 recommended practice can be downloaded by clicking here.
