Movie previews may get quieter

Have you found yourself playing back movie soundtracks lower than the "calibrated" level? Do you instinctively try to cover your ears during previews at the theater? If so, you're not alone.

The New York Times reports that a study undertaken by Dolby Laboratories involving 334 students from the University of Southern California demonstrated that most viewers think movies are too loud. The students (average age: 20) viewed the action thriller Con Air at the recommended playback level and were asked for their reactions afterward. The majority rated it "too loud."

Dolby is working with Hollywood studios to scale back the sound level of previews (known as "trailers"), commercials, and feature films. Recent advances in audio technology have greatly increased recording engineers' power to move air in the theater (and in the well-equipped home). One unexpected result is that theater owners are receiving an increasing number of complaints from movie fans. Their response, like yours, is to turn down the playback level to make the heart-stopping sound effects and bombastic music tracks in action-movie trailers acceptable for most viewers.

This lowered level has the unfortunate effect of making some dramatic dialog inaudible. Result at the SMPTE Film Conference last spring. In the paper, Allen points out that, although the baseline sound level hasn't risen much, the increase in available dynamic headroom has led to the present level of excess. He notes that mixing engineers on studio sound stages now routinely wear hearing protection at work. He also theorizes that some of the unpleasantness in studio sound may be attibutable to overdriven, underpowered ampifiers---an artifact familiar to all audiophiles. "Riding gain," a recording engineer's method of adjusting level to keep a recording from overloading, is also a skill theater projectionists and home-theater fans need to master---at least until more progress is made toward more tolerable sound levels.

The film studios will probably learn to use more discretion as they get comfortable with the new technology, but at present they're as unlikely to stay within reasonable limits as a 16-year-old with a brand-new motorcycle. The complete text of Ioan Allen's paper, entitled "Are Movies Too Loud?," can be viewed at Dolby's web site: