For the album, each serial's incidental music was reassembled into short "suites" and although most of the music had been recorded in mono it was, for this compilation, remixed into stereo with sound effects added on to some tracks. The album was re-released in 1992 by Silva Screen records as Earthshock - Classic Music From The BBC Radiophonic Workshop Volume 1, with bonus tracks including "The Worlds of Doctor Who", a track recorded by Mills as a B-side to Dudley Simpson's 1973 "Moonbase 3" single, which featured a mix of music with sound effects from Planet of the Daleks before following with Simpson's "Master's Theme" and finishing with music from the serial The Mind of Evil .
For the album, each serial's incidental music was reassembled into short "suites," and although most tracks were originally recorded in mono, they were remixed for this compilation into stereo with sound effects added to some. The album was released again in 1992 by Silva Screen records as Earthshock - Classic Music From The BBC Radiophonic Workshop Volume 1, featuring bonus tracks such as "The Worlds of Doctor Who," a track Mills recorded as the B-side to Dudley Simpson's 1973 single "Moonbase 3," which included music with sound effects from Planet of the Daleks, followed by Simpson's "Master's Theme" and concluding with music from The Mind of Evil.