The scariest aural effects can often be invisible

The closer you listen, the more terrifying “No Country for Old Men” becomes. That’s because in scenes so quiet as to be almost completely silent (save for the low, ghostly howl of the West Texas wind), every isolated sound factors in the characters’ uphill battle for survival.

“In the novel, Cormac McCarthy refuses to tell you what people are thinking and just describes what people are doing,” explains Ethan Coen, whose adaptation (with brother Joel) emphasizes the same level of physical detail. “That can make for really engrossing moviemaking.”

Consider two separate scenes set in cheap hotels. In the first, Llewelyn Moss (Josh Brolin) retrieves a briefcase full of stolen money from an air-conditioning vent while the menacing Anton Chigurh (Javier Bardem) executes a team of rival bounty hunters in a neighboring room. Sound designer Craig Berkey concocted the muffled noise Chigurh’s shotgun makes when fired.

“Everyone expects a gunshot to be really loud, and you don’t want to give that up because it’s really stimulating to the audience, but at the same time, there’s supposed to be a silencer, so we were looking for ways to convey that it’s still like a concussive event,” says supervising sound editor Skip Lievsay.

Moss doesn’t hear the shot, but he can feel it as the walls and vents carry the reverberations between the rooms.

Moss escapes the close call and retreats to another hotel, where he holes up with a shotgun, waiting, listening. A chair falls offscreen. Moss calls the front desk and hears the phone ring, unanswered. The floorboards creak and Chigurh’s proximity sensor beeps as he approaches, then falls silent.

“The challenge was to make those clues as low as possible in the soundtrack as to be just audible,” says Joel, who insisted on pressing what Lievsay refers to as the “edge of perception.” From the sound effects provided, the audience deduces that Chigurh has arrived, eliminated the hotel clerk and stalked Moss to his room.

“Actually shooting that crap is pretty damn boring, as you can imagine,” Joel says. “The view of the door and the light under the door, and now you hear something over here.” The excitement came in editing, where the Coens (working under the pseudonym Roderick Jaynes) tested “how far you could milk something without it becoming too much.”

According to Ethan, “We had three bailout points, none of which we availed ourselves of,” just in case the timing didn’t work. Adds Joel, “You just have to proceed by feel in terms of what you think is appropriate in building and sustaining the tension.”

That unnerving balance factors in other scenes, too, such as the coin toss at the convenience store. Chigurh snacks on a bag of cashews while grilling the clerk — “friendo.” There’s menace in the air, augmented by the absence of music (Carter Burwell’s score, less than 16 minutes in the entire film, consists mostly of “dying or bending notes,” often subliminally tied to car steadies or other ambient sounds, Ethan points out).

To punctuate the scene, Chigurh lays the crumpled cellophane wrapper on the counter, where the resulting noise cuts the silence.

In his days working with Martin Scorsese, Lievsay devised a rule: If a director uses an insert, then it has to have a sound. “It doesn’t always have to be literal,” he says. “Otherwise, why would you put the shot in there? You’re changing it up, you’re drawing another card from the deck.”

Nearly all the sounds in “No Country” are explained by the environment — with one notable exception. As Chigurh claims his first victim, choking an unsuspecting deputy with his handcuffs, the roar of a non-existent freight train echoes the sounds of their struggle.

Because of the diminished use of score, Lievsay explains, “We had to find a way to give Chigurh his normal theme with sound instead of using a music piece, so we started experimenting with that distant-thunder rumble, and that led Craig to the train motif.” Those locomotive noises shadow Chigurh throughout, subliminally reinforcing his heavy, unstoppable approach. “The idea,” Lievsay says, “was Chigurh is a force that comes and goes, and like the fate he represents, he’s on the wind.”

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