Issue link: https://digital.copcomm.com/i/1500716
C A S Q U A R T E R L Y I S U M M E R 2 0 2 3 61 Scoring mixer Shawn Murphy A/85 Techniques for Establishing and Maintaining Audio Loudness for Digital Television." That said, the document "CALM Best Practices" does quote A/85 directly. It's important to note at this point that the commonly referenced BS.1770 iterations (1, 2, 3, and 4) are not specs, rules, or guidelines. They are technical white papers that outline the algorithms that measure LKFS. There is no specific rule or recommendation made in 1770; CALM compliance is contained solely in A/85. This is where things got a little messy, and I've never understood why because A/85 is very clear about what it recommends. It speaks at length about measuring an "anchor element," usually dialogue, as in "…forms the Anchor Element in the majority of television programs. During production, it is usually possible to isolate the dialogue and to measure its loudness accurately, regardless of the overall dynamic range or style of the finished program." The other way to measure loudness is to measure the "full program" content, which ignores any anchor element and instead measures loudness across all content in all channels of a mix. There's been a lot of movement around this in the few years since Greg and I wrote that original article, and to start with, it seemed like it would be an improvement. However, in reality, the targets for mixers to hit have gotten evermore blurry and disparate between the platforms to which we all deliver. While the technical information contained herein will be accurate, I am going to editorialize some of the other, more subjective factors because there are some areas in which we as an industry are not doing ourselves any favors—and I'm not going to try and hide my frustration. The issue has become so politicized that I need to anonymously quote some people who were directly involved in A/85 because of the implications of going on record about it, despite their input being as close to gospel as it's possible to get. So, here's the background, along with some definitions. The reason we're even talking about this at all is because of the CALM Act, which is a well-intentioned but fuzzy piece of legislation designed to stop the ads on TV blasting in at what seems like 10 times the volume of the show you were just watching. The CALM Act itself doesn't give any specific instruction per se, other than to follow the guidelines laid out in the document "ATSC Dolby Media Meter