I Swear, from director Kirk Jones, is a biographical drama about John Davidson, a Scottish teenager who was diagnosed with Tourette's and labeled insane by his peers. Davidson campaigning for better understanding and acceptance of the condition, finding purpose in life and ultimately receiving his MBE from the Queen in 2019. The film was released in September and stars Robert Aramayo, Shirley Henderson, Maxine Peake and Peter Mullan.
Simon Hayes, AMPS, CAS, served as production sound mixer on the feature and shares his experience, which focused on capturing authenticity.
“When director Kirk Jones and I first sat down to talk about I Swear, it was immediately clear that authenticity would drive every creative decision. The story follows Tourette’s campaigner John Davidson, portrayed by Robert Aramayo, and Kirk’s vision was unflinching: audiences must experience Tourette’s as it really is - unfiltered, unpredictable and human.
“For me, that meant discarding many of the conventions of feature-film sound. Tourette’s doesn’t respect coverage or continuity; it happens in realtime. To honor that truth, the sound department had to embrace unpredictability, not control it. From our first conversations, Kirk and I agreed: we’re going to support our cast’s original performances in every way possible.”
Rethinking the rules
“In conventional film dialogue recording, we strive to control chaos,” says Hayes. “We ask actors not to overlap lines, to avoid interruptions, to give us ‘clean takes.’ On I Swear, those rules went out of the window. Robert remained fully in-character, free to tic or vocalize whenever he felt the impulse. The supporting cast, Maxine Peake, Shirley Henderson & Peter Mullan could respond naturally - sometimes speaking over him, sometimes waiting, folding his tics into their reactions and rhythm.
“That spontaneity produced dialogue tracks that defied standard cutting logic. There were sudden outbursts, whispered lines, unpredictable overlaps and a constantly shifting dynamic range. From day one, Kirk told me he never wanted to replace any of it in ADR. ‘If the goal is to put the audience inside John’s head,’ he said, ‘then every tic, every break in rhythm has to stay.’ That mandate shaped every technical decision we made.”
No rehearsal. No second takes
Hayes and Jones quickly established the mantra of being ready for anything, as they weren’t going to shoot a re-take.
“There were no rehearsals, no chance to preview levels,” says Hayes. “We rolled straight into performance. For the car interior scene, which has since become one of the film’s most recognizable and talked-about moments, featuring Robert Aramayo and breakthrough actor Andrea Bisset, who lives with Tourette’s, I placed our two digital Schoeps CMD42/MK41 boom microphones behind the front-seat headrests, aimed directly at each actor and feeding Sound Devices’ A20 digital transmitters. Every microphone was routed through the Nexus receiver into the Scorpio recorder, each with two discrete tracks: one with digital gain that I rode during the scene, and a second at unity gain - a pure 24-bit AES signal for safety. I had no idea how the scene would play out, and in fact, the rehearsal, which we shot as the first take, is the one that went into the film!”
By keeping the entire chain digital, from capsule to recorder, and running roughly 16 to 20dB lower than usual, Hayes gained huge headroom.
“We could handle explosive tics, shouted dialogue, without distortion or compressor/limiter artifacts,” he notes. “Due to staying completely in the digital domain, we could still capture the whispered lines too, without any recording chain noise, while preserving every nuance of breath and emotion. The actors were free to deliver whatever came naturally, knowing that the sound team would never ask them to repeat a moment for technical reasons.”
The sound of space
Another early decision was to avoid using lavalier microphones for interior shoots. Hidden mics can be useful, but Hayes feels they often flatten perspective and erase the character of a room.
“Because I Swear was shot largely single-camera, I had the luxury of letting the environment breathe as the boom positions could match the cameras frame,” he explains. “Each location - from family living rooms to echoing tower blocks - became part of the performance. I wanted the cinema audience to feel like they were in the room with John Davidson, and the best way of doing that sonically is to celebrate the room acoustic.”
The production used boom mics at all times rather than relying on the forced close-up perspective of lavs, or auto aligning booms and lavs.
“The wide shots don’t sound artificially close; they sound expansive and truthful,” he shares. “Reflections and air carry the emotion of the scene. I told Kirk, ‘I want this to sound like the best documentary you’ve ever heard.’ That became our philosophy: embrace the acoustics rather than fighting them.”
Two booms, total trust
None of this would have been possible without long-time boom operators Arthur Fenn and Robin Johnson.
“When we joined the production, it was just the three of us heading north to work with Kirk’s small, tight-knit crew,” says Hayes. “From the start, Arthur and Robin understood what was needed - two booms on everything, constant communication, and an instinctive feel for performance.”
Their precision and understanding allowed them to capture overlapping dialogue and spontaneous interaction without breaking the flow.And because lavs weren’t used indoors, every emotional beat depended on their mic movement and timing.
“The cast immediately became advocates for production sound, understanding that our presence on-set was about protecting their performances, not interrupting them,” he shares.
Perspective as storytelling
One scene that encapsulates the philosophy features John, walking to his new flat in a tower block while a group of kids on BMX bikes hear him before they see him.
“His tics echo around the concrete courtyard,” shares Hayes. “Traditionally, this would be covered with hidden lavs to maintain dialogue clarity, but that would have robbed the moment of perspective. Instead, we positioned a wide boom nearly a hundred meters away at its widest point, recording exactly what the kids would hear - a stranger’s voice bouncing off the tower blocks, growing louder - and closer - as he approached. The sound places the audience in their shoes, not John’s. It’s storytelling through perspective, achieved entirely through production sound.”
Workflow
I Swear was the first feature Hayes recorded entirely in the digital domain. From the Schoeps CMD42 capsule through the A20 transmitter and Nexus receiver into the Scorpio, the signal path remained pristine, with no analogue gain stages or colouration.
“The CMD42’s internal digital output allows gain adjustment after the capsule, keeping the noise floor constant at any level,” he explains. “Combined with digital transmission, the signal remained transparent end-to-end. For a film with violent dynamic swings, that consistency was invaluable.”
Each boom delivered two parallel tracks: a "hot" one with digital trim rides and a "safe" one untouched. It gave Hayes the flexibility of using a limiter on the gain-adjusted tracks, knowing the dialogue editor could go back to the lower-level track to remove any compressor/limiter in Pro Tools during post.
Editorial partnership
The success of the workflow depended on seamless communication with the editorial department. Before shooting began, Hayes was in discussions with picture editor Sam Sneade and dialogue editor Emma Butt to outline what they could expect.
“We all knew the tracks would be dense - full of overlaps, interjections and noise that would never be ‘clean.’ But they weren’t problems to solve; they were the film’s language.”
Throughout production Hayes kept in contact with Butt, providing reference notes and highlighting problem spots.
“She designed a dialogue editorial strategy that preserved rhythm, rather than imposing order,” he notes. “Her sensitivity to performance meant the raw material retained its emotional energy all the way into post.”
Once Jones and Sneade moved into the cutting room, Hayes stayed in close contact.
“Sam’s approach to picture editing aligned perfectly with ours in sound,” he recalls. “He embraced the overlaps and rough edges, cutting picture rhythmically around them instead of forcing the tracks to conform to continuity. The edit became musical - built on the cadence of real life.
Sound design
When sound designer Niv Adiri joined the process, he understood immediately that his role wasn’t to replace what was capture, but to extend it. Niv’s sensitivity to texture meant that the production track always sat at the emotional center of the mix.
“His atmospheres and design elements didn’t smooth the sound; they deepened it,” says Hayes. “In scenes of heightened emotion, Niv built subtle resonances around the production track - small reflections or low-frequency textures that amplify tension without undermining realism. It was a dialogue between departments, not a relay race, where one hands off to the next. Big shout out also to Joe De Vine, whose creative input on Niv’s team was greatly appreciated.”
VFX and mic visibility
Another essential partnership was with James Blann, the film’s director of photography, and the team at Automatik VFX, who embraced microphone visibility as part of the modern workflow.
“On rare occasions when we shot two cameras on interiors, they supported booms being in the wide shot frame, as removal was a simple compositing task, with the boom operators protecting each take by leaving a couple of seconds clear of the booms before swinging in as Kirk shouted ‘action,’ so we had a take specific plate on every clip, helping the VFX team match if there were changes in ambient light on a take for take basis.”
Supporting the Tourette’s community
Beyond craft, I Swear carried a moral responsibility. Several cast members live with Tourette’s, and the film’s mission was to represent their experience honestly.
“It was vital that our recording process supported them, not constrained them,” says Hayes. “By creating a sound environment where they could tic freely without concern for ‘spoiling’ a take, we gave them genuine creative freedom. They felt seen and heard, literally. The set became a space of trust, where production sound wasn’t policing noise but protecting expression.”
Editorial
When production wrapped, Hayes joined Jones, Sneade, 1st assistant editor Annalisa Boyd, Butt, and Adiri for extended playback sessions, reviewing each scene in detail.
“By the time we reached the final mix, the soundtrack was a tapestry woven from production, design and score,” says Hayes. “Nothing felt isolated. Every decision traced back to the set, to the moment the microphone captured real emotion.”
Final mix
The last stage of the journey took place at The Post Republic, where re-recording mixer Dan Johnson brought all the threads together.
“Dan’s mix was nothing short of marvelous,” says Hayes. “From the first playback, I could hear how sensitively he had approached the material - matching the emotional tone of Kirk’s picture edit while respecting the dynamic, naturalistic production tracks.
“When I visited the final mix, I offered notes grounded in the same ethos that had guided the shoot: I wanted the mix to always match camera perspective and the room’s acoustics. Dan achieved that beautifully. As the camera moved closer, the sound moved closer. When it pulled back, the ambience expanded. Every shift in perspective felt organic, never manipulated.”
For Hayes, I Swear stands as proof that sound, picture and story can develop together, rather than sequentially.
“Working with Kirk Jones reaffirmed what I’ve always believed: great sound begins long before the first take,” Hayes shares. “It starts with a director who values it, an editorial team that respects it, and a post pipeline that protects it. From prep to final mix, communication never stopped. Every department - camera, costume, VFX, picture, sound - shared information and priorities. That transparency allowed us to make fast, creative decisions on-set instead of defensive ones in post. Kirk’s leadership encouraged that openness. His instinct was always to protect performance first, and he trusted his heads of department to find the technical solutions. That trust made the work exhilarating.”