The Alchemists of Sound is a great 2003 documentary taking a look at the BBC Radiophonic Workshop.
It features lots of fantastic archival footage, plus interviews that look at not just the history of the workshop, but the history of electroacoustic music and sound effects.
The Alchemists of Sound (Part 2)
The Alchemists of Sound (Part 3)
The Alchemists of Sound (Part 4)
The Alchemists of Sound (Part 5)
The Alchemists of Sound (Part 6)
who was the guy in the background cant find out anywhere… ?????