<I>Guardians of the Galaxy Vol. 2</I>: Blockbuster sound design
Issue: May 1, 2017

Guardians of the Galaxy Vol. 2: Blockbuster sound design

The Guardians of the Galaxy just saved the universe from Ronan the Accuser (Lee Pace) and deposited the purple power stone safely into the hands of the Nova Guard on Xandar. Marvel’s Guardians of the Galaxy Vol. 2, in theaters now, picks up the story several months later as the Guardians seek out the father of Peter Quill (Chris Pratt).

Supervising sound editor David Acord, who led the post sound team on the first Guardians of the Galaxy film, welcomed Addison Teague as co-sound supervisor on Vol. 2. Both are part of Skywalker Sound in Marin County, CA (www.skysound.com). 

To handle the tremendous amount of sound design, Teague and Acord began work on the film during the director’s cut last June. Teague was embedded with the picture department at Disney’s Riverside Editorial in Burbank, CA, where Marvel had set up camp. Picture editing, visual effects and previs, plus sound editorial, are all self-contained in one location. Teague says, “It’s amazing what you can learn by being in the same space as these people, and they liked having access to Dave or me just by walking down the hall. We always want to get involved early on so that we have an imprint on the track and our sounds get carried along. That way, there are fewer surprises when you get into premixing and the final. This setup gives us a better chance to give them what they want in terms of sound.”

Director James Gunn wanted what he described as a ‘pulpy’ vibe for the sound on Vol. 2, which Acord translates as having a Flash Gordon (1936) sci-fi sound. He applied that direction to the sound design of Ego’s power. Ego (Kurt Russell) — Peter Quill’s father — can produce a power that ranges from benign to malevolent. While it’s always a challenge to create a sound for something that doesn’t exist, Teague notes it was even more challenging since they lacked a visual reference initially. “Since we were involved so early, they were still developing some ideas themselves,” he says. 

Teague and Acord created a demo session for Gunn that contained roughly six different power sound ideas. Gunn could pick and choose specific aspects of the different ideas to create new ideas. “We evolved the sound until it became what he was looking for, but it was a trial and error process. We were evolving the sound while James [Gunn] evolved the visual effects,” says Acord. 

Ego’s power needed to represent the sound of light. It also had to be versatile: magical and beautiful in one instance and gigantic and evil in another, yet still retain its core characteristics. “There had to be a signature thread so that you could tell acoustically that this was the same power,” says Acord. 

Acord created one core element of Ego’s power sound by recording a ladle swirling around inside a metal mixing bowl. This produced a resonant sound akin to that of rubbing the rim of a wine glass, only more metallic. Acord applied flange to create a warpy feel and time-stretched the sound to give it a screamy vocal quality. He used Ina-GRM Tools Warp plug-in to help round off sharp edges, particularly when the power needed to sound more benevolent. “I could use Warp to lower it, soften it, to give it an airy quality and quiet it down,” he says. 

Another key element was a warbly layer that added a feeling of movement to the power sound. Acord recorded ice swirling inside a bowl. He pitched that down and did multiple passes of Denoise processing with iZotope’s RX 5. “You’re left with pure transients — with all of these little plinks and buzzes that happen in this cacophonous way. It no longer sounds like swirling ice, but it added this nice layer of constant movement,” says Acord.

One challenge for Teague was creating the voice of baby Groot. Groot only says three words, “I am Groot.” Since that’s his response in every situation, the inflection really matters. So Gunn created a one-off script for actor Vin Diesel, the voice of Groot, explaining what Groot was really saying in each scene.  

Baby Groot’s voice is higher in Vol. 2 — much higher than Diesel could perform naturally. Because Diesel has a very deep voice, it was easy to get into extreme pitching, like eight or nine semi-tones. Teague experimented with several different scenarios, like having Diesel perform it higher, and then pitching that up. “If he performed it the way he did on the first film and we pitched that up to the frequencies we wanted for this film, it was a very different result than if Vin performed it in a higher pitch and then we pitched it just a little bit,” says Teague. In the end, Teague found the best result came from Diesel performing his lines slower because “there was less artifacting when we pitched it up.”

Diesel performed 417 takes of “I am Groot.” On the ADR stage, they set up live pitch processing so that Gunn could hear an approximation of the final sound. But they didn’t record the processing on the take since the realtime processing had a significant amount of artifacts. “But this setup allowed us to know what the end result would be if he performed the line in that register. Vin performed all the lines in a higher register, his normal register, and then slower. We needed him to perform this full range of options because we only had him for one day on the ADR stage,” explains Teague.  
Other sound design highlights for Teague include creating a new jet pack sound. Using a Sanken CO-100K high-frequency mic, he recorded a culinary torch that he waved around and then pitched those recordings way down. He also recorded a handheld Mattel Electronics football game from the '70s. And got to create fun new '80s video game/arcade sounds to accompany it.

Acord’s favorite sound in the film is that of Groot walking across the floor while he’s soaking wet. Acord says, “His squishy, wet little feet are all sound design. We used this stuff called Flarp, which is this squishy, fart-in-a-can toy for kids. Also, there’s some wet sponge and a leather creak. That’s a great sound.”