The Beach Boys' Good Vibrations took 90 hours of recording time over 6 months to finalise, and cost 16 thousand dollars (1966). Sheesh, and it sounds like something they knocked up in a couple of hours. Apparently the idea behind the track was Brian Wilson's notion of telepathic signals between humans and animals, (Pet Sounds?). Considering how far off the rails he eventually slid, I think this was a sign of things to come.
These and other facts from a fascinating book - Theremin: Ether Music and Espionage, a biography of the life of Leon Theremin, the inventor of the instrument that makes the eerie space noises heard on Good Vibrations and many of the early Sci Fi movie sound tracks.