Inside Limbo

Story: John Broomhall

BRIEF BUT POWERFUL

Andersen’s original brief was simple: ‘not like a videogame’. Which is perhaps not what a typical videogame developer wants to hear. But Playdead left him free to explore this notion of nothingness, and he found the iterative experimentation/decision-making process both engaging and inspiring.

Andersen explains: “I learned some interesting things. Trying to make Limbo sound like an old film, I put everything into mono but discovered I couldn’t engage with that sound. It just wasn’t immersive enough. I saw Limbo as such a tiny world, so I was trying to reduce all the sounds to something very simple and thin sounding. I distorted sounds, then afterwards I expanded them again to really spatialise them; almost anti-phase.

“I ventured into using antique audio devices; wire recorders, spring reverbs and tape recorders. In linear media you can make your mix from moment to moment, whereas in a game the sounds might be mixed differently every time you play. I discovered that using old machines created a homogenised sound. Running all of my sounds through an old tape recorder made them sit very well together in the mix.

“When I put my own bespoke-recorded physics sounds in the game, they sounded too real; the surface of the sound didn’t fit the image. So I ended up running them through an old spring reverb. I put the reverb to zero to use it as a hardware filter, which made the bottom disappear so it sounded narrow and thin. Because the sounds lost a lot of their main identity and clarity, they suddenly became more generic; I could use the same sounds for a metal box or a wooden box. It all contributed to making the world very small and defined.”

PLAYING WITH EMOTIONS

Andersen sees the overall narrative structure built into Limbo’s audio as his biggest contribution: “No one really pays attention to that aspect. For me, the overall framework played a very important part. I was trying to achieve the creation of a world structure with the audio going from the quasi-realistic, naturalistic sound you hear in the forest to becoming more abstract and almost transcendent as the boy progresses through the world.

“You have the most horribly traumatic moments and the sound suddenly turns into something melancholic, contrasting with what you see. It makes sense to me to say, ‘Ok, so this boy travels through all this violence and I have to respond to this in some way’, otherwise people would just get habituated to it. I wanted to make it feel like the boy got habituated to the violence rather than the player, leaving the player to wonder how they should feel. Sometimes the music would almost represent forgiveness.

“Limbo is really distinct; something unto itself. Despite real world references, the sound helped to make a ‘limit’; a wholeness to the experience as you move from A to B — a development and an ending.”

Small wonder then, that Playdead asked Andersen back to design music and audio for their second production Inside, an equally dark and atmospheric development of Playdead’s creative genius. Those who experienced Inside’s audio demonstration at UK conferences The School of Sound and Develop Conference in Brighton were blown away, with one impressed delegate declaring they ‘may as well give up sound design right now’.

This time, Andersen’s audio development is characterised by a blurring of sound design and sound implementation. In other words, he is creating game audio using the audio middleware and game tools themselves.

“It’s one thing to create great sounds,” said Andersen. “And another to make them come alive in the game. Creating Inside’s character sounds often required an iterative process where we’d first go and make sound recordings, start developing an implementation strategy for them and then, based on our learnings, go back and re-record in a way that would fit the implementation strategy.

“The more the sounds are shaped by various game parameters, the more the game comes alive. We expanded that approach by feeding output from the sound back into the game. For example, the sound system for the boy’s breathing features a real-time interpolation between natural breathing rhythms — ranging from relaxed to panic — extracted from actual sound recordings and the rhythm of his footsteps. The rise and fall of the boy’s chest is controlled by the ‘breathing’ audio data.

“On a global level, a lot went into implementing custom sound transitions between death and re-spawn in order to maintain immersion through the unloading/reloading process. That attention to the overall experience by embracing death/re-spawn is something I often miss in games. There’s an intangible dynamic between real-world and game-world time there. Even though my character dies and I go back in game-world time, real-world time still frames my experience, and I easily get annoyed hearing the same line or music cue over again as I die and re-spawn. However, if I quit the game and get back to it after a few days I probably do want to hear those sounds again. Making a distinction between load and re-spawn, and creating unique mix and music transitions for every situation are integral to Inside’s sound design.”

INSIDE JOB

Compared with the Limbo development experience Andersen had a much longer and deeper involvement with Inside, working closely with the team over years rather than months. This, combined with the respect Limbo’s plaudits have won him, has opened some significant doors for audio integration.

“It’s allowed me to get at the core aesthetically and technically,” said Andersen. “Doing things that are impossible to introduce later in the process, like prototyping game-play where timing and mechanics are hooked on music or clock time, rather than the usual but much more unstable game-time. It’s great for tight integration between music and game-play but a technical challenge… you have to demonstrate it’s worth the effort early on.

“Early involvement means sound becomes part of the creative toolset in forming the game’s structure, not a bolt-on. For sequences in which game-play and sound played very well together but eventually became too repetitive sonically, I could suggest changes in the game’s structure. That worked in reverse with the team suggesting sound structure changes, enabling us to create coherent musical build-ups that encompass entire sections of the game.”

Just like Limbo, Inside exhibits a unique sonic identity — not so common in today’s games — though according to Andersen, it’s more subtle this time: “It’s the graininess of early 12-bit digital audio hardware like samplers and delays. By means of convolution, we’re running an ’80s (then) state-of-the art hardware reverb dynamically in-game, which really makes the audio elements meld together. Aesthetically, I took inspiration from ’80s horror B-movies, which often feature a synthesiser soundtrack. I didn’t want any synth per se, just a vague association. I’d already been playing around with a real human skull in the studio in order to create bone-conducted sound. I made a workflow of processing synth sounds through the skull using audio transducers and contact microphones, and then restoring them. The result has a sombre, chill quality. As in those film scores, haunting tones often score something horrible taking place. My goal is that, like a siren song, the gloomy, faint echoes of synths will coax the player forward… to whatever end.”