Delia Ann Derbyshire (5 May 1937-3 July 2001) was a British composer who oversaw the BBC Radiophonic Workshop beginning in the 1960s. She was considered a visionary in her use of sound and voice and her early works are pioneering efforts in what is now known as electronica. Groups from this genre such as Orbital and Portishead have acknowledged her influence.
Her best-known single work was her arrangements of the Doctor Who theme by Ron Grainer. While Grainer composed the basic melody, it is Derbyshire who provided the iconic sounds and form of the theme. Grainer attempted to secure co-writing credit for Derbyshire, but due to rules in place at the time she was not allowed to receive a songwriting credit, although the Workshop and she would be regularly credited on the series.
Derbyshire created three theme arrangements. The first was used only for the pilot version of An Unearthly Child and was almost identical to the version used in the televised version, except for additional sound effects such as a thunderclap. The second version was the televised version used from An Unearthly Child to The Moonbase. When a new title sequence was introduced with The Macra Terror, Derbyshire revised the arrangement and, with some minor refinements over the years, this version was used through The Horns of Nimon (it was to be used for the last time in Shada, but that story was never completed or televised).
In 1980, Derbyshire's arrangement was retired and replaced by a new one by Peter Howell. Elements of Derbyshire's arrangement have reemerged in the arrangements introduced by Murray Gold in 2005 and late 2007.
In 2008, the BBC announced the discovery of two hundred sixty-seven tapes of experimental and demo recordings made by Derbyshire in the 1960s and 1970s. Their existence were not known until after her death. Among the recordings found were Doctor Who-like special effects, as well as an experimental electronic music track that has been noted for its astonishing similarity to the electronic dance music of later decades.
Derbyshire also composed some pieces for the BBC's stock music library, some of which were eventually used in Doctor Who as incidental music. Such contributions to the stock library include "Chromophone Band" (appearing in The Macra Terror), "Blue Veils and Golden Sands" and "The Delian Mode" (both of which were used in Inferno).