When you think of Dolby, you may think of moments that are, well, loud: the Imperial Star Destroyer flyover in Star Wars, for instance, or the epic battle that ends Marvel’s The Avengers.

But recently, Dolby has been involved in making one element of your home theater experience quieter—the commercials.

Toward the end of the last decade, an age-old problem with TV commercials came to a head. Advertisers were making their commercials really loud—much louder than the shows that the ads interrupted—to get viewers’ attention. Turning down the volume during commercial breaks was an annoying necessity.

The engineers at Dolby noticed the problem and devised a technology called Dolby® Volume to help. Built into A/V receivers, sound bars, and other home theater products, Dolby Volume detected volume spikes, like those in commercial breaks, and brought them back in line with the rest of the broadcast.

But Dolby Volume only solved the problem for households with home theater components that included this new technology, leaving millions of households in the United States to continue fumbling for the remote during every commercial break. And those millions weren’t happy—they were flooding the US Federal Communications Commission (FCC) with complaints.

In 2010, Congress passed the Commercial Advertisement Loudness Mitigation (CALM) Act. The CALM Act, which took effect in 2012, requires that commercials have the same average volume as the programs they accompany. Simply put, you can set the volume once and watch the whole program without being blasted by shouting hucksters.

The CALM Act is great for TV viewers, as evidenced in the sharp decline in complaints to the FCC about commercial noise since its passage.

But complying with the law can be a challenge for content creators. Loudness, like any attribute that ends in “-ness,” is subjective. It’s a quality that is difficult to accurately and objectively measure. And, of course, some scenes require louder (and even softer) elements to convey the right emotion or mood.

A change for the better

The Dolby broadcast team is helping to make CALM Act compliance simple and seamless for content creators and broadcasters alike. Dolby engineers worked with broadcasters and other engineers from around the world to develop an internationally accepted method for making loudness measurements.

While it may seem easy to recognize a loudness difference between programs, in order to fix loudness problems, broadcasters and content creators needed professional tools to measure program loudness and understand the differences that we hear. Dolby engineers invented the Dolby Broadcast Loudness Meter LM100 and the Dolby Media Meter, which provided an independent method to measure program loudness. And that in turn led to the ability to control the loudness of programs.

Once content creators have made sure everything is as it should be, our technology uses metadata to tag content that complies with the law. New audio codecs from Dolby will identify “trusted content,” essentially giving it a digital seal of approval. That makes it easier for broadcasters to ensure that everything they send to your living room complies with the law—that’s a particularly popular feature with broadcasters because it means they don’t end up paying fines when they violate the CALM Act.

Obviously, even at a reasonable volume, some ads are still annoying—especially when you see them for the 20th time. But we’re proud of our role in helping to control commercial volume—after all, if we have to have people hawking their goods in our living rooms, at least they can use their “inside voices.”

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