"Dick Mills was in charge of sound effects and all the rest then, and he put the voice through a ring modulator or whatever gizmos he'd got at the time to make it sound a little more electronic"

John Leeson's quote is referring to the sound results utilized in the popular British science fiction television series, Doctor Who. Dick Mills was the sound effects engineer for the program and was accountable for creating the renowned electronic voice of the Doctor's robotic companion, K-9. Mills used a ring modulator, a gadget which modulates the frequency of a signal, to give the voice a more electronic noise. This technique was used to produce the special sound of K-9's voice, which has actually become a staple of the Doctor Who franchise. The use of the ring modulator was an imaginative and ingenious method to produce an unique sound for the character, and it has ended up being a specifying function of the show.