TV Loudness: The Wild, Wild West - TvTechnology

TV Loudness: The Wild, Wild West

How effective is the CALM Act?
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ASHLAND, ORE.—Back in the day of three television networks, analog NTSC, and epic westerns, radio stations engaged in endless loudness wars, but television stations strove to match their audio loudness with other stations in the market.

Those were the days! Commercial producers, of course, tried to make their commercials as loud as they could get away with. This was a constant battle, with the commercial producers maintaining that their product did not deflect the vu meter any higher than program audio.

We knew, of course, that although that was true, loudness could be increased through using audio compression to increase the average audio level, while keeping the peak level legal. So the vu meter did not go too high, but it dwelt near the peg. From the network side, there was constant effort to keep commercials from being offensively loud.


As we moved into the digital age, this battle continued, but now the program producers also wanted to push audio levels to the limit. As the person who wrote and maintained the high-def program delivery spec for a major broadcast network, I engaged in many conversations with program producers about the audio levels on their programs. I remember one producer insisting passionately that they really, really needed that extra one dB that got their show rejected.

The digital television era also brought us 5.1 channel sound to accompany HD, and I recall one energy water commercial that pegged the peak meter of every audio channel, including the surrounds and the subwoofer, aka Low Frequency Effects. Meanwhile, another network went for maximum loudness as an objective, a practice that continues to this day.

The loud commercials situation produced the Commercial Announcement Loudness Mitigation (CALM) Act, a law with a clever title. Let me quote the opening paragraph of the FCC’s web page on the Act:

Federal Communications Commission (FCC or Commission) rules require commercials to have the same average volume as the programs they accompany. In the Commercial Advertisement Loudness Mitigation (CALM) Act, Congress directed the FCC to establish these rules, which went into effect on December 13, 2012.

As a loudness reference, the FCC mandated use of ATSC A/85, “ATSC Recommended Practice: Techniques for Establishing and Maintaining Audio Loudness for Digital Television.” From what may be determined from the ATSC website, A/85:2013 appears to be the current version of this Recommended Practice. It specifies the use of AC-3 tools such as Dialnorm and Dynrng , and also use of the loudness measurement algorithm contained in ITU BS.1770, updated in 2013 to BS-1770-3, which included a better loudness algorithm than BS.1770. In fact, BS.1770 is currently up to BS.1770-4, published in 2015, but it does not appear that the ATSC documentation has caught up. 

[Read: CALM Act Facts Revealed]

Parenthetically, your author worked on some of the early stages of the development of BS.1770, as did many audio experts. A number of algorithms were considered, going back as far as the algorithm used in the CBS Loudness Meter devised in the 1960s, and it is accurate to say that, while the CBS loudness algorithm was indeed better than some of the more recently devised ones, the algorithms used to measure perceived loudness have seen real improvement in recent years. The FCC regulations apply to broadcast, cable, and satellite TV, but not to internet. Sounds good, right? Or does it?


For a while now, I have been out of the loop, a pure viewer, and my observations have been that these regulations are frequently honored in the breach. Particularly in the cable world, audio loudness levels vary dramatically between channels, which is not, in itself, a violation; but it is distracting to the viewer, many of whom switch among channels.

In the AC-3 world, the honest, reasonable application of Dialnorm should render this a non-problem. On the broadcast side, there is, at least, consistency in the average loudness level of programming, element-to-element, as the broadcast networks take pains to assure it. The commercials, however, are a different story. Sometimes, the levels vary commercial-to-commercial, with some commercials being softer than the program material, and some louder.

There is one broadcast network whose commercials and network promos are consistently louder than their program material. I have confirmed this by noting it in a large market and a smaller market. And because I now live in market #138, the local commercials inserted into the pods are notably worse than the network commercials, on all network affiliates. This is partially because this market would seem to be where all the 1960’s screaming puker DJs ended up, now doing local commercial voice overs. A number of the locally produced commercials are not just loud, they are totally obnoxious. There are of course some very well-produced local commercials as well. Some.

Cable is frequently worse than broadcast for loud commercials and uneven commercial loudness. The worst, of course, is commercially-supported online TV. It appears that the commercials are typically inserted from different servers from the one that runs the programming, and possibly from multiple servers during a single commercial pod. The non-commercial streaming services with which I am familiar do a nice job of maintaining even program loudness. The commercially-supported services, i.e., the online streaming services of the broadcast and cable networks, are still on a steep learning curve with regard to relative loudness between program and commercial elements.”

To sum up, it appears that in 2018, the CALM Act is about as helpful to the consumer as the Do Not Call List.