CALM ACT TV LOUDNESS RECOMMENDATIONS REVISED

Posted on April 4, 2013 in ATSC News

Supporting the FCC in its ongoing implementation of the Commercial Advertisement Loudness Mitigation (CALM) Act, The ATSC has published revisions to its Recommended Practice A/85, Techniques for Establishing and Maintaining Audio Loudness for Digital Television. A/85 provides the industry with uniform operating strategies that optimize the audience listening experience by eliminating wide swings in sound levels.

The revised version of A/85 includes an update of the reference to the International Telecommunications Union Recommendation ITU-R BS.1770- Algorithms to measure audio programme loudness and true-peak audio level.

The revised A/85 now references ITU-R BS.1770-3. Version 2 of BS.1770, adding “gating” (excluding low level passages from the measured value) to the measurement algorithm. The update to version 3 of BS.1770-3 made some very minor editorial updates to the loudness measurement text and a modification to the true-peak measurement algorithm.

ATSC Recommended Practice A/85:2013, dated March 12, 2013, is the successor document to Recommended Practice A/85:2011, dated May 25, 2011.

In response to consumer complaints about loud commercials the CALM Act was enacted into law on December 15, 2010, requiring the FCC to adopt the relevant portions of ATSC A/85. The FCC adopted new rules in December 2011 requiring TV broadcasters, cable operators and other multichannel video programming distributors to be compliant by December 13, 2012.

Posted in ATSC News