Horror Sound Design’s Secrets: How Audio Experts Craft Bone-Chilling Scares

Sound has, in my opinion, the biggest part to play in creating tension and scares. As an exercise, if you ever watch a horror film on mute you’ll instantly see it’s not anywhere near as frightening. For me, the best tension is crafted using sounds or tones with no fixed pitch.

Simply creating a ‘movement’ in the sound-bed with undulating volume and pitch manipulation makes for an anxious feeling of being unable to identify the source, immediately putting you on edge. Whether this is done delicately or heavy-handed, the effect is surprisingly similar. We’re often afraid of what we don’t know or understand, so if you can’t tell what a sound is or what’s making it, that’s when something sounds scary!

 

Creating scary sounds is super fun, but unless used correctly, they won't have the desired effect. Good horror sound isn't just about the jump scares, it's about the moments in between – the ebb and flow of silence, or emptiness that builds tension. 

In horror it's also common for vision to be restricted, low lighting for example limits the information available to an audience. To compensate, the brain will rely on sound to fill in the gaps, making you more sensitive to what you are hearing. So when your brain is desperately searching for sound cues to reassure you that you're safe, the absence of sound can be the scariest thing you can hear. 

There is also a commonly used device in horror sound design known as infrasound. This is the use of frequencies typically below the range of what humans can hear. We find infrasound scary because we have evolved to associate these frequencies with danger. They occur in nature when created by earthquakes, volcanos, avalanches, etc. This effect is commonly replicated by layering ambiences with low frequency bass rumbles or drones.

I'll often take regular sounds and significantly pitch shift them down to create new, dark textures or even automate slow pitch shifts down by a few semitones to create a sense of ‘falling’. Combined with spatial effects such as reverbs or echoes, the most innocuous of sounds can become terrifying.

I also find that ‘dirtying’ your mix can really help. Liberal use of distortion and saturation can create sounds that are extremely unpleasant to listen to – which under most circumstances is the opposite of what we're trying to achieve as sound designers. However in horror, it can be an invaluable tool, so sometimes forgetting the traditional approach to gain staging and pushing into the red can be extremely effective!

When it comes to the perception of danger and horror, I like to apply the power of semiotics to drive the audience’s emotions in desired directions. 

I like ‘hiding’ sounds that reference uncertainty and distress – like screams, sirens, roars, tinnitus, heartbeats, etc. – in my sound design and compositions to enhance the perception of discomfort. For example, an avalanche layered with a rumble or a scraping sound combined with a pitched-down whale call sounds a lot more threatening than the actual sound on its own. It becomes unique and almost foreign. 

Introducing contrast and unfamiliarity can be an effective way to push the audience outside the auditory comfort zone. Sharp loudness shifts and the use of silence can be great tools here. Additionally, I enjoy experimenting with tuning my sound design around the music. For instance, if you alter the pitch of tonal ambiances like room tones or even birds and insects in various tonalities, you can create more dissonant worlds and textures. 

Audiences are emotionally reacting to sound on a subconscious level which makes it a crucial instrument in horror and thriller films. When done in an elegant way, it can be very effective and powerful.

 

I think there’s three elements to a successfully scary soundtrack. Authenticity, relentlessness, and silence.

Authenticity is vital; our brains are wired to respond instinctively to certain sounds and when these sounds are authentic and raw, they resonate deeply. Triggering our innate fears, the more plausible the sound, the more real that emotional connection is. 

The threat is real! It’s rare in commercials, but I love using repetition in sound, and in horror, when that sound is relentless, it can be terrifyingly inescapable. This kind of auditory pressure immerses us in a state of unease, ensuring that we never quite feel safe. It mirrors the relentless nature of the horror itself, trapping us in a cycle of dread.

Finally, I’d like to give a shout out to silence. Nature abhors a vacuum, and silent moments in film allow the imagination to run wild, and not in a good way. By depriving the viewer of information their worst fears fill the void. It messes with their head.

You can always follow a period of silence with a jump scare but remember it’s not big and it’s not clever, but I ask you, what’s worse than a jump scare? The absence of a jump scare. Don’t give them the relief they’re craving. Turn the screw. Double down. Mwahahahahahaha!!!

Have you ever watched a horror scene without sound or music? It’s just not as scary, right? This is the perfect example of how powerful sound can be in storytelling. 

Sound design is a key tool for manipulating audience emotions, heightening tension, and amplifying fear in horror films. Sudden loud noises, eerie tones, and prolonged dissonant sounds trigger a fight-or-flight response in the body, making us feel on edge. Sounds like creaking doors, distant screams, or sharp, dissonant tones signal danger, prompting the brain to brace for threats. 

One technique often employed is the use of infrasound – sound frequencies below 20 Hz, too low for the human ear to hear but still felt as vibrations. These sounds are often associated with natural disasters like earthquakes or volcanic eruptions – or even animal screams – situations where danger is imminent. Our bodies instinctively react to these inaudible frequencies with unease and discomfort. 

Another powerful method is dissonance. While harmonious music soothes, dissonance unsettles the brain, preventing it from finding calm, which leads to anxiety. Discordant frequencies, irregular rhythms, and unexpected shifts in sound trigger mental agitation, keeping the audience in a state of tension. Dynamic changes in volume, tempo, and tone also fuel horror. The classic 'jump scare' thrives on the abrupt shift from quiet to loud, while a well-executed crescendo—like the gradual rise of a heartbeat or breath—mimics the natural sounds our brains link to danger, escalating fear. 

Lastly, silence is an underrated tool. Prolonged quiet, interrupted by sudden, sharp sounds, creates an imbalance that heightens suspense. The right use of eerie soundscapes plays on our imagination, making us visualise unseen threats and amplifying the horror. In the end, it’s the creative manipulation of sound that turns ordinary images into deeply unsettling experiences.