Stay up to date with notifications from The Independent

Notifications can be managed in browser preferences.

The Shepard tone: The auditory illusion that makes Hans Zimmer's Dunkirk score so powerful and even shaped the screenplay

If it feels like the tension is constantly ratcheting up, that's because it is

Your support helps us to tell the story

This election is still a dead heat, according to most polls. In a fight with such wafer-thin margins, we need reporters on the ground talking to the people Trump and Harris are courting. Your support allows us to keep sending journalists to the story.

The Independent is trusted by 27 million Americans from across the entire political spectrum every month. Unlike many other quality news outlets, we choose not to lock you out of our reporting and analysis with paywalls. But quality journalism must still be paid for.

Help us keep bring these critical stories to light. Your support makes all the difference.

Dunkirk is perhaps unprecedented in how it feels intense from start to finish. This was very much by design, as the film was written and scored so that it would be intense essentially ad infinitum.

Enter the Shepard tone, an auditory illusion consisting of a superposition of sine waves separated by octaves.

As Vox explains in its brilliant explainer video above, it sees a middle octave scale at constant volume, a top one fade out and a bottom one fade in, tricking the brain when played on loop and creating a sense that pitch is only going up and up up and up and up.

Spectrum view of ascending Shepard tones
Spectrum view of ascending Shepard tones

Supercomposer Hans Zimmer used the Shepard tone extensively in the Dunkirk score and it is also found in several other Nolan films.

He is clearly fascinated by it (its illusory nature feeling akin to his general obsession with the non-linearity of time and space) and even influenced how he wrote the screenplay for Dunkirk, a film which consists of three storylines that you could think of as three octaves.

He told Business Insider:

"There's an audio illusion, if you will, in music called a ‘Shepard tone’ and with my composer David Julyan on The Prestige we explored that, and based a lot of the score around that.“It's an illusion where there's a continuing ascension of tone. It's a corkscrew effect. It’s always going up and up and up but it never goes outside of its range. 

"And I wrote the [Dunkirk] script according to that principle. I interwove the three timelines in such a way that there's a continual feeling of intensity. Increasing intensity. I wanted to build the music on similar mathematical principals. So there's a fusion of music and sound effects and picture that we've never been able to achieve before."

Dunkirk is in cinemas now. You can read our review of it here.

Join our commenting forum

Join thought-provoking conversations, follow other Independent readers and see their replies

Comments

Thank you for registering

Please refresh the page or navigate to another page on the site to be automatically logged inPlease refresh your browser to be logged in