How was the TARDIS materialising/dematerialising sound originally created?
The TARDIS in Doctor Who..
The TARDIS dematerialisation sound effect was crated by the BBC Radiophonic Workshop in 1963. The "key" element of the original sound was a set of house keys being scraped on a piano wire.
That sound is just house keys scraping along piano wire. It is layered with some static some reverb in order to make the TARDIS sound.