From Sinfini Music via Colossal:

Before starting work on our Well-Tempered Clavier animation (codenamed WTC for the ten weeks it took to complete), director and visual artist Alan Warburton immersed himself in Bach’s music by boarding a ‘random’ bus and listening to the first prelude and fugue for over two hours. ‘By the time I’d found my way back home,’ he says, ‘I had digested how complex the music was – especially the Fugue. I realised I needed to keep the animation simple so the viewer could focus on the music.’

But if the animation itself was going to be simple, producing it would be anything but. Alan’s incredible design incorporated many thousands of separate CGI lights, every one of which had to be tailored to the precise duration of Pierre-Laurent Aimard‘s note strikes. ‘I needed to find a way of automating the process of these turning on and off in time with the music,’ says Alan. With no midi file of the performance available, he was faced with the seemingly impossible task of matching every note of a stand-in midi file to the recording, by ear alone.

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