Fear is a funny thing. It can feel pretty unpleasant but it’s actually a complex system designed to keep you alive. Our bodies and brains have spent millions of years getting used to the world but we still scare so easily.
Although most of us try to avoid that feeling of dread in the pit of your stomach, some people go out of their way to experience fear – they sit in dark, quiet rooms and watch horror films by themselves. When it comes to making a truly scary horror film, nothing sends your imagination into overdrive quite like good sound design.
One of horror filmmaking’s tricks of the trade is using non-linear sounds to scare audiences. Our brains have a natural aversion to non-linear sounds that goes back millions of years. A non-linear sound is essentially a sound that has gone beyond its natural volume and becomes raspy and unnatural – the roar of a sabre-tooth tiger for example.
For maximum effect, horror films use well-placed non-linear sounds that can also incorporate rapid frequency jumps, nonstandard harmonies, chaotic noises and instruments being pushed beyond their normal range. For a perfect example that combines a few of these techniques, look no further than the master himself, Alfred Hitchcock, and the shower scene from Psycho. If you prefer your scares a little simpler, the Theremin’s strange frequencies and otherworldly tones can still creep out even the bravest horror film buffs.