Julian Nott's Peppa Pig demo lasted for 20 years

Julian Nott scored the Peppa Pig pilot for free as a favour to a friend from film school. The recording was a demo, the sort of thing expected to disappear once a production found its feet. Instead, those same ten seconds opened the programme for 20 years and were replaced only last year. A final version is sometimes just a draft nobody dares disturb.

The theme has two chords. Nott notes that classical musicians who laugh at three-chord pop songs may consider this an outrage, but his assignment was smaller and less forgiving: write something fast, cheerful and instantly memorable in ten seconds. He also left gaps between the phrases so the animator could insert Peppa's oinks. Silence had a speaking part.

The marimba, timpani, glockenspiel and vibraphone colours that became associated with the show did not emerge from a grand aesthetic plan. There was no budget, so the entire cue was made with synthesisers and samples. Nott chose the instruments whose sampled versions sounded most convincing at the time. A technical limit disguised itself as a style, then became one.

Nott now hears the tune in cafes, airports and trains, usually leaking from a child's tablet. It gave him financial security, although that may be limited comfort to parents woken by it at six in the morning. He wrote ten seconds of music. The repeat button supplied the rest of its cultural life.