‘Amanda Knox’: How the Audio Team Found the Eerie Sounds for Documentary

Amanda Knox Netflix
Courtesy of Netflix

A brutal murder. A sensational trial. Exhaustive TV coverage of the headline- making case of an American in Italy convicted of killing one of her roommates and later acquitted by a higher court. Those are the broad strokes of the new Netflix documentary “Amanda Knox,” which premiered at the Toronto Film Festival. The film is about the highly publicized case of the student from
Seattle who, in 2007, was tried and found guilty of murder.

But visuals tell only part of this dramatic story. Sound design and music do a lot of the heavy lifting.

“The big challenge in both the design and mix was giving emphasis to all the case material and the details,” recalls audio post producer and re-recording mixer Tom Paul, of New York audio house Gigantic Post. “There’s a lot of text and graphics, and we had to find the sweet spot between over-melodramatic, cheesy swishes and being right on point. We did that using the right amount of reverb and levels. We also wanted to make all the archival footage, which is intercut with interviews, feel very present.”

A key consideration: the parts where the prosecutor visits the crime scene.

“We added specific broken-glass sounds and foley footsteps so that it’s like a movie,” says Paul, “and very experiential and emotional.”

Paul was brought onto the project through writer and editor Matthew Hamachek. When Hamachek had to leave for a prior commitment, Paul in turn enlisted supervising sound editor and re-recording mixer Chris Stangroom of New York’s Hobo Audio, with whom he has collaborated on many jobs over the years.

Stangroom received all the audio elements from Hamachek and directors Rod Blackhurst and Brian McGinn, and, with his team, dug into the job at hand.

“We went through all the dialogue, cleaned it up to ensure it was audible and usable, and then tackled the sound effects,” he says.

Stangroom says there were big challenges on a number of levels. “We had to deal with footage from news outlets, police footage, home video, and archival,” he says. “Those different sources were not focused on the audio quality.”

Stangroom worked at re-creating audio tracks for scenes in the Italian town of Perugia, where the crime took place, and Seattle, Knox’s hometown. He then focused on what he calls the “emotional” sound design.

“We got the music pretty early on and created some ‘drone-y’ sound effects to keep the tension up,” he says. “That was a big note from the directors — give it an eeriness without straying into horror-film territory, and to underscore the intensity of the events.”

Adds Hobo CEO Howard Bowler, “Compared with all the other documentaries we’ve done, this was very exacting work to come up with the right sonic direction.”