You might not have heard the term ‘Foley’ before, but you will possibly have witnessed it – probably in the last film or TV programme you watched – without even realising.

Foley is the process of adding sounds to films, television and radio programmes after they have been recorded, pioneered by Jack Foley in the silent film-era of the early 20th Century. The sound effects are artificial, created with props or sources that are often radically different to what appears on screen. In cinema, the sounds of monsters or futuristic technology, for instance, have been created using every from envelopes to breezeblocks and biplane motors.

It’s not just for fictional TV or movies either. In a radio documentary, The Sound of Sports, Dennis Baxter describes how sounds are added to sporting events, from rowing to athletics. In horse racing, for example, it would be impossible to lay microphones around an entire course, so a pre-recorded track is played over the top. But instead of pre-recorded horses, they use the slowed-down sound of a buffalo stampede. Sometimes Foley sounds may be used because they feel more ‘real’ to us than the real thing.