Tubeway Army was of course in essence Gary Numan. Gary wrote the music and lyrics, sang, and played all the instruments save the bass guitar (played by his best friend, Paul Gardiner) and the drums (his uncle, Jess Lidyard). Gary also acted as his own Producer. In addition, he was managed by his father and his mother was responsible for his costumes and makeup.
Gary initially formed the 'band' as a punk outfit. Using a stripped-down, punk sound to take advantage of the latest trend in British record labels who were signing every band that sounded remotely like the Sex Pistols. Gary stumbled onto a Moog synthesizer at the Beggars Banquet studio and, much to the label's dismay, immediately incorporated the instrument into his music. This forever changed his sound and arguably helped give birth to the New Wave sound.
Gary threw out all of the guitars for the follow-up to Replicas(1979), The Pleasure Principle (1979). Opting to utilize the synthesizer sound almost exclusively. At this point, Beggars gave in and allowed Gary to release the album using only his name and Tubeway Army was no more.