Acapella, meaning "without accompaniment" has been a popular singing style for years. In the Sixties, a couple of singing groups brought acapella to the fore, and for some hitherto unexplored reason, put it in the service of Science Fiction. One major group in that regard was the Swingle Singers, about whom I got nothing, and the other was the Mike Sammes Singers. Their tunes were not always acapella, but even when instruments were involved the smooth and easy scat singing, a mellifluous doobie-doobie-doo-dooby-dooby-doo sound, was all over the skiffy landscape.
You'll remember the Mike Sammes Singers theme tune for Supercar, of course, a Gerry Anderson beaut.
And the Mike Sammes Singers theme tune for Gerry Anderson's Stingray. Anybody who doesn't love the theme tune for Stingray is not allowed in my club.
And while we're at it, there's the Mike Sammes Singers theme tune for Gerry Anderson's The Secret Service.
Ok, maybe it was just Gerry Anderson and the Mike Sammes Singers. The rest of science fiction probably just muddled along on the theremin until Massive Attack was invented.
Today, I came across this, and was made new again.
(Edited to improve links, 07/2017)