3D and IMAX may receive top billing, but the secret weapon of Alfonso Cuarón’s Gravity is something the audience will never even see. From the sound design to the score, Gravity features one of the most innovative and inventive sound mixes to make its way to theaters — one that breaks with modern movie convention in significant ways. It’s a film where space is actually silent, touch is the best way to hear, and dialogue whirls around the audience in an immersive 360-degree cyclone.
Two of the artists who helped bring it to life are sound designer and supervising sound editor Glenn Freemantle (Slumdog Millionaire, 127 Hours), and sound re-recording mixer Skip Lievsay, a frequent Coen brothers collaborator. We spoke with them both to learn about the techniques and tricks used to bring Gravity’s aural panoramas to life — and the technology that made it possible.

THE SOUND OF SILENCE
Glenn Freemantle first got involved with Gravity in December of 2010, when he was asked to do the sound design for a 45-minute previsualization that was going to be screened for studio executives. Over a few weeks he created a 5.1 mix with Cuarón that conceptually set the stage for what was to come: a film in which the audience would hear sound effects the same way the characters did. In space there’s no air to transmit vibrations, so that means total silence — unless you’re touching something and your body itself serves as the conduit.
Glenn Freemantle: It was at that point that we decided to do the sound design from the perspective of touch through vibration, and contact, in the whole film. Right from the beginning. We did that type of thing that you see right on that first little temp mix. Obviously we went and elaborated, and we shot loads and loads of stuff and you know, tried to refine the whole thing, but that was the beginning of the concept.
And that whole opening, I just loved it. You know, the silence — and then you come around, and then you hear. The great thing with the film and your contact, [is that] you hear things from the inside. There’s the whole thing of incorporating Sandra’s breath and her heartbeat. It was right in there, right from the beginning as well. So your whole contact with sound is through touch — but also through the person.
Every time something’s banging against something, and she’s not touching what it’s banging against, you don’t hear it. So it’s pretty intricate and very detailed and very time-consuming, but it pays dividends. It actually becomes a thing of beauty, because you’re not just bombarding everybody with every sound all the time.
Skip Lievsay: [Sound] is like a comfort layer that we all take for granted, you know? It helps us figure out which way to turn if we hear a car coming. We can hear that. There’s like a whole layer of things that we day-to-day deal with via sound, where we get our input directly from sound. And when you remove that, it’s like a huge safety net that you’re removing.
A LA CARTE AUDIO
Transmitted through touch or not, Freemantle and his team still had to create the sounds themselves. To start, he and foley artist Nicholas Becker visited a studio outside Paris where they submerged guitars in water. Recording with underwater microphones called hydrophones as well as contact mics, they rubbed different items along the guitar strings. Some of those recordings became the sounds audiences hear when Sandra Bullock’s character is hung up on a parachute during one of the film’s pivotal scenes.
GF: Hugo [Adams, foley editor], one night he was at a party, and he knew someone who knew someone who worked for NASA. Bang. So we get all this information from NASA. What are these tools made of, the stuff they use in space? And they were great. … But they use [the same kind of tools] in car manufacturing, they use them in hospitals, in operating theaters. So I thought, “Brilliant.”

So we went into General Motors, and we went into their test area. … We recorded on all these different mics, and then we recorded the robots that make their cars, and we stuck mics to them. Anything we could get that was metal or moving. We even recorded these air conditioning units for inside [the spacecraft]. We just recorded a stack.
It’s like making an a la carte meal. You need the best ingredients you can get, and then gradually, like you’d design a dish, the sound comes. You know what you want, and you’ve got the initial sounds, so you think “Oh, we can add a little bit more.”
The same philosophy applied to the background radio chatter. Rather than rely on pre-written dialogue performed by voice actors, the sound team turned to people that truly knew what they were talking about.
GF: Through our contacts, my company got hold of a group of NASA guys that worked there. And I set them up in a hotel room, and we Skyped them one day, and we sort of said, not giving away the plot or anything like that, but gave them scenarios that might happen in space. And recorded about four hours of proper space talk and scenarios and chatter. … We had four of them, and they had their own mics so we got some absolutely amazing stuff. It’s very subtle, but it’s the detail that you go to, to try and create this world that is true to what would be happening.
IT’S ALL IN THE FUTZ
George Clooney and Sandra Bullock spend the majority of Gravity’s running time ensconced in bulky spacesuits, communicating over helmet-to-helmet transmissions. When mixing the dialogue, Skip Lievsay created a special EQ to “futz” the audio — making it sound like it was coming over a radio rather than from a person in the room. He could then adjust that element based on the demands of a given scene. In emotionally intimate moments, he and Cuarón opted for less-processed audio, so words sounded clearer and warmer; other times they could dial up the futz in order to accentuate the distance between the players.
SL: The other side of the dialogue question was the panning. Alfonso likes the idea that the words are attached to people. If you’ve ever seen Children of Men, you see that nearly all the dialogue in that movie is panned [to match the actor’s position on screen]. I like that idea. It removes a certain veil of film shenanigans where the old simple idea is that all dialogue comes from the center channel — which is a film construct. It doesn’t happen that way in life, and it isn’t really necessary to do that in the modern film formats.

Director Alfonso Cuarón
"Alfonso likes the idea that the words are attached to people."
Let’s say a person within the geometry of a scene, a person comes in the door — which would be geographically in the rear, where the left surround would be, let’s say. If you put the sound of the door and their “Hey, what’s going on?” dialogue over in that channel, nearly every filmmaker will tell you, quite scientifically, that will distract the audience and throw them out of the scene … Even though the actors on camera turn and look to that direction, and then the camera spins over to see the person entering, most filmmakers will argue with you that that is a distraction and that you need to hear it on the center channel, or maybe on the left side — maybe. And I think one of the great things about cinema is the presumption that things are happening outside of the proscenium. That the film is pointed in one direction, but everything else is still going on outside of that frame.
SCORE
Steven Price started on the project as a music editor before his ambitious ideas earned him the composer role. Cuarón’s primary directive was to avoid a traditional symphonic score, something that Price took to heart — with a twist.
SL: Price created a lot of sound with samplers and digital equipment, but he also recorded a score at Abbey Road, which they then took and manipulated those sounds. So there are quite a lot of orchestral movements in the film, but they’ve all been futzed and kind of wrangled a bit so they don’t sound so dry and ordinary. So within that idea, Price and his crew did a fantastic job of delivering material that was orchestral emotionally, but not literally.
"Price and his crew did a fantastic job of delivering material that was orchestral emotionally."
GF: He got into this amazing idea of changing score … When we weren’t going to use sound — you know, like traditional sound design, like blowing something up — to let the music be like a ballet at that particular point. And even the timings and what he was using. We know what he was using all the time, and we’d talk all the time as well. So it was a very cohesive journey through the film.
Gravity’s score received the same kind of dynamic panning as the sound effects and dialogue. Lievsay and music editor Christopher Benstead used 5.1 mixes of the score broken down into groups of instruments and sound types — called “stems” — that they could then manipulate individually across the 7.1 soundstage while mixing. Lievsay controlled the volume while Benstead handled the panning.
SL: What we did basically was, we would rotate the whole track. So if you imagine a steering wheel, on the top of the wheel is LCR [the left, center, and right audio channels behind the movie screen], and on the bottom of the wheel is left surround and right surround. And you turn the steering wheel, you can see what that’s going to create panning-wise. … So the emphasis goes from front to back, so it creates a gigantic feeling of movement when you reverse roles, basically, and the energy which is always in the front rotates to the back, and the afterburn — in the form of the reverb — ends up in the front.
THE DOLBY ATMOS MIX
Gravity was originally mixed in 7.1, but Freemantle is quite clear that the ultimate version of the film's sound is the Dolby Atmos mix. Launched last year, Dolby’s latest platform is an impressive leap beyond traditional surround sound on a number of fronts. With 5.1, audiences had those three LCR channels behind the screen, with two additional banks of speakers powered by the left surround and right surround channels. 7.1 split those surround channels up; filmmakers could target the left side or the left rear groups discretely, for example.
Atmos adds speakers to a theater’s ceiling for overhead effects, but more importantly, it does away with the concept of fixed channels almost entirely. Instead, it allows sound designers to place sound elements in extremely specific locations within a theater, down to the individual speaker. It offers the ability to do things like pin Clooney’s voice to a specific point on the theater wall, and then have it travel speaker-by-speaker towards the screen, rather than mushily pushing it towards the entire left bank as in traditional setups.
"All of a sudden the theater is space, around you. You’re in the world!"

GF: I remember saying to Dolby, “Look, there’s this film I’m doing, and it would be the film for Dolby Atmos.” It’s got Dolby Atmos written all over it, you know? Because all of a sudden the theater is space, around you. You’re in the world! And also, because we’re not going to slam it forward, millions of things all the time — we’re going to be very specific, even in our approach of how we use the sound. I mean very, very detailed, but very clear, and accurate with everything.
After completing the original mixes in the UK, the team relocated to a stage at Warner Bros. for the Atmos version. The panning information from the original mix had already been transferred into the system, so it was time to experiment.
SL: Once we had copied the [7.1 audio] pans, we then took the pans and pushed them further into the new channels that we had. That’s when we found the glory of Atmos, which is a lot of very high-fidelity destinations for your sound. Everything sounds so much better because everything beyond the front screen is being played in full-frequency channels.
GF: Dolby Atmos and these immersive sound systems work brilliantly when you can move things through the spaces throughout the room, and you can actually hear them. When you’ve got masses of things going on, you lose that clarity. … And also Atmos then creates this smooth transition around [the theater], and over the top. Like when George is going around and he looks up at the stars. He looks at Earth, and the voice is crisp, and they twist right around and come back out the other side. But it’s seamless. So sound becomes real emotional, because you’re contacting the characters and you’re moving with them.
Gravity is now playing in theaters. The film’s sound team also included re-recording mixer / sound design editor Niv Adiri, supervising dialogue / ADR editor Nina Hartstone, sound design editor Ben Barker, dialogue editors Emilie O’Connor and Gillian Dodders, sound effects editors Eilam Hoffman and Danny Freemantle, and assistant music editor Robin Baynton.