Just when I get the TV volume adjusted to the optimum level, a commercial comes on and rattles the house like a sonic boom. Who’s the Einstein who decided I should listen to commercials at a level loud enough to rupture my eardrums? —Rick Gray
For as long as I can remember, home theater has had the same problem, namely, while the parts of a movie or TV show full of explosions are loud enough to strip varnish off a coffee table, dialogue at the same volume is barely comprehensible because it’s too damned quiet. Thus, you either have to constantly adjust the volume or resign yourself to the possibility of permanent ear damage every time you watch an action movie. What’s the deal? —Dan Rosenbluth
Several audio techniques are at work here, two of which, interestingly, work in opposite ways. But the motive is the same: Noise sells.
Viewers have complained about loud TV commercials since the 1950s, but advertisers paid no heed, figuring people couldn’t ignore your message if you screamed it in their ears. In the 1960s, the FCC began warning broadcasters to lower the volume but made no serious attempt at regulation, and industry efforts to self-police didn’t accomplish much either.
Things got worse in the era of digital TV, with improved technology greatly increasing the range of discernible sound volume, better known as dynamic range. Eventually, Congress stepped in, passing the Commercial Advertisement Loudness Mitigation (CALM) Act in 2010. The law directed the FCC to set advertising loudness standards for broadcasters, cable operators and other video distributors. By Dec. 13, 2012, a commercial’s average sound level must be the same as the average loudness of the surrounding programming. The idea is that once you get the TV volume adjusted to a comfortable level, you won’t risk having your eardrums ruptured by a sales pitch.
Human ingenuity being what it is, the new rule may not entirely solve the problem. Imagine a commercial skillfully interweaving tranquil footage of bunnies and butterflies with equal intervals of air-raid-siren-level noise. On average, the result is 100 percent FCC compliant. %u2028
Improved TV technology works both ways, however. Check your owner’s manual to see if you have a function called automatic gain control, audio compression or peak limiting. If you do, and you have the moxie to navigate through the byzantine array of menus and options on the average TV, they’ll enable you to control the peak noise level. My assistants Una and Fierra discovered their 5-year-old television had two of the aforementioned options, so there’s a decent chance yours might too.
That brings us to the related problem of loud movies. Increased dynamic range during regular programming was designed to enhance the vividness of the home-theater experience by reproducing the gamut of sounds you experience in real life. Unfortunately for your hearing, the approximation of real life favored by Hollywood tends to fixate on the whispers of the bedroom on the one hand and battling robots on the other.
Action movies are particularly problematic. Audio researchers found that whereas a typical episode of the sitcom Friends had a nontaxing dynamic range of 6.6 “loudness units,” the 1999 film The Matrix had a range of 25 units. The eruption of noise during The Matrix’s action sequences is part of its charm, of course, but such extreme dynamic range pushes the limits of what even the most sophisticated home system can reproduce, making it virtually impossible to find a comfortable volume level.
Once again, though, technology is your friend. The Dolby 5.1 system, for example, includes a “midnight mode” that compresses the dynamic range, lowering the sound peaks and raising the valleys to make a concussive soundtrack more listenable.
But here’s the surprising part. Where the movie industry uses increased dynamic range to make more noise, the music industry uses dynamic range compression to do the same thing. Dynamic compression is a major weapon in what’s been called the “loudness war,” the steady increase in the volume of rock and pop music. Going back at least to Phil Spector’s “wall of sound,” music producers and engineers have always been trying to make their records sound bigger and more exciting than the competition’s, and one way of getting a song to jump off a jukebox is simply to make the recording itself louder.
Because you can only turn the sound up so far before it becomes distorted, it eventually became standard practice to compress the dynamic range while cranking the gain until the song was uniformly loud—nevermind the loss of sound quality. Since the mid-1980s, the average loudness of CDs has increased by a factor of 10, a trend if anything exacerbated by the shift to MP3 players. How better to make a track really pop in shuffle mode than to torque its effective volume? Thus the curious paradox: A century of technological progress has culminated in popular recordings with less dynamic range than an Edison phonograph cylinder of 1909.
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