What Makes Horror Movie Music So Scary?


This Halloween the team at The Sync Project asks the question: does scary music tap into a dark and unwelcoming place deep within the human psyche, or have we just become conditioned to expect and react to certain types of music along with a scary film? The answer seemingly lies more with nature than with nurture, but film directors are very adept at exploiting our deepest fears through a range of tried techniques that we have become accustomed to…

The Devil’s Music

Let’s start by looking at a certain musical arrangement: the tritone. Defined in the simplest possible terms, a tritone is “a musical interval of three whole steps.” For those who can read and understand music, the definition of a tritone can get a lot more detailed than that, so it’s best illustrated with an actual audio sample.

We immediately recognize the tritone from its use to create tension in film, or even to act as a marker between scenes in a play. It’s not that the tritone arrangement is particularly scary per se, it’s that it’s lacking in harmony (it’s dissonant) and is somehow incomplete, throwing the listener off balance and leaving you expecting more (or rather fearing the worst) as it’s played over and over again…

In the Middle Ages the tritone was named “diabolus in musica” (devil in music) and the church in fact banned it from being played. It was seen as the very antithesis of God, which the church believed would be represented by beautiful angelic harmonies rather than incomplete sonic dissonance.

In addition to the tritone, directors use a range of other powerful techniques to foster tension film, including silence punctuated by sudden noise (pretty much any horror movie); pipe organs (eliciting a Gothic feel); the speeding up and slowing down of bass sounds (think of Jaws again); playing a series of chromatic notes (i.e. any twelve consecutive keys on the piano, including the black ones); and high-pitched screeching sounds (Hitchcock’s Psycho.)

Wagner's Opera  Tristan Und Isolde  famously features a tritone in the opening sequence to signal the ill-fated character of Tristan

Wagner's Opera Tristan Und Isolde famously features a tritone in the opening sequence to signal the ill-fated character of Tristan

Screams From The Cradle

Let’s take a closer look now at those high pitched screeching sounds, because this is where we turn from the nurture to the nature side of the debate…

In 2012, an evolutionary biologist by the name of Daniel Blumstein – an expert on animal distress calls – was with some colleagues in Colorado catching yellow-bellied marmots (a type of large squirrel) for a research project. Blumstein noticed that occasionally, when caught, the marmots would rapidly blow air past their vocal chords to release a so-called “non-linear sound” – other wise known as a scream. Blumstein then set about conducting an experiment to find out just much these non-linear sounds influenced people’s reactions when used in film soundtracks, proving that there is indeed a causal effect.

What’s most interesting about Blumstein’s study however is the simple observation of the “non-linear noise” produced by animals – particularly young animals – when scared. Because this is where the music used in horror films is tapping into fears that take us right back to the cradle. There are few things more dissonant and off pitch than the cry of a baby, or more disturbing than the scream of a scared child. These are sounds that elicit an immediate biological response, putting our senses on edge and spelling in no uncertain terms: danger ahead.

This reaction is what film directors are exploiting when their musical scores take us towards the high pitches, the screams that punctuate the silence, or the eventual resolution of the tritone or chromatic scale in a screeching crescendo invariably accompanied by the proverbial bloody hand or face at the window…