Hearing in the Dark: How Horror Developers Design Soundscapes You Can Navigate By

In Hollowmere, the frogs are a warning system. On a quiet night in the marsh, the chorus is constant, rising and falling in a loose rhythm around ranger Ada Kell. When something moves beneath the water nearby, the frogs closest to it go silent first. Players who notice that pattern start reading the gaps in the chorus like a radar screen. Players who do not tend to have a much harder time.

That kind of information is what Callum Achterberg, audio director at Bracken & Bone, spends most of his time thinking about. “Horror audio has a reputation for being about loud noises,” he says. “The loud noises are maybe five percent of the work. The other 95 is building a world quiet enough that the player can hear where things are.”

Sound as a map

Hollowmere’s hand-drawn map fills in only as you explore, and the boardwalks seem to rearrange themselves when you retrace your steps. That makes sound the most reliable navigation tool in the game. Each ranger cabin has a woodstove with a distinct crackle, audible from a surprising distance, so players learn to walk toward safety by ear. Running water marks the edges of the marsh. Reverb tells you whether you are in open reeds, under trees, or inside a structure. Bracken & Bone recorded most of those sounds on location in a coastal wetland over two seasons, including several nights spent sitting still in waders to capture how a frog chorus reacts when something large moves through the water. It does not go silent all at once, Achterberg says; the quiet spreads outward from the disturbance, which is exactly the effect the game reproduces.

Achterberg’s team built those cues with positional accuracy in mind. Every important sound is placed in 3D space and filtered by what lies between it and the player. A creature behind a wooden wall sounds muffled and slightly low; the same creature behind reeds sounds thinner but clearer. “If you can tell the material between you and a sound, you know whether it can reach you,” he says. The team also limited how many sounds can play at once in quiet areas so that important cues are never buried. In the tensest stretches of the marsh, there may be only five or six sources active, and each one means something.

We mix for headphones first. Stereo speakers and soundbars collapse a lot of the vertical and rear information, and in a game where the threat is under the water, below you is the direction that matters most.

Callum Achterberg, audio director at Bracken & Bone

Abyssal Choir and the sound you make

Bracken & Bone’s next game, Abyssal Choir, turns that idea around. The creatures in the flooded Thalassa Deep station hunt by echolocation, so the player’s own noise becomes the danger. Breathing gets louder as oxygen drops; metal boots ring on dry decks; a dropped tool can carry through an entire section. Achterberg says the team has built a separate mix layer just for player-generated sound, so you can always hear yourself clearly enough to know how much noise you are making. Playtesters found that unnerving at first, because it made them self-conscious about every movement, which was the point. The team has since added a subtle rhythm to the diver’s breathing that slows when you stand still, so players can calm themselves by stopping, and hear the station settle around them.

Getting the most from horror audio at home

• Use headphones or a headset, and set the game’s audio output to its headphone mode if it has one. Both Bracken & Bone games do.
• Turn off any “night mode” or dynamic range compression on your system. It raises quiet sounds and lowers loud ones, which flattens the cues the mix depends on.
• Avoid stacking spatial processing. If the game has its own 3D audio mode, pick either that or your headset’s virtual surround, not both.
• Set the master volume so the quietest ambient layer is just audible, then leave it alone.

Kestrel Audio’s Nightjar headset, which supports per-game spatial profiles, was used during parts of Abyssal Choir’s audio review sessions, and Kestrel has published a Bracken & Bone–tuned profile for Hollowmere in its companion app. Profiles like this are a starting point rather than a requirement; Achterberg’s main advice is simply to listen closely. “The marsh is telling you things the whole time,” he says. “Most people only notice when it stops.”