Wht about the original “Doctor Who” theme music? Peformed by the BBC Radiophonic workshop, it is an early example of analog synthesized music.
CC
Isao Tomita put out a couple of albums of electronic music in the early ‘70s.
Pink Floyd had some electronic cuts (like the main theme to More) but the album contained a lot of less “electronic” cuts as well.
http://www.youtube.com/watch?v=qz9EjhTfc2A
I'll see if I can find an album (late 60s early 70s) that included a cover of the Dr Who theme along with other electronic songs (the Dr Who cut almost goes reggae dub at a point).