When this came out in Oct 1989 the cover stated that it was "ambient house for the e generation". Until this release the ambient house scene was basically Dr Alex Paterson playing DJ sets built around BBC nature recordings and NASA space broadcasts in the back room of Paul Oakenfold's night "Land of Oz" at Heaven. The original 22 minute 12" feels very much like a mini set from that "chill-out" room, with waves of "loving you" by Minnie Ripperton fading in and out of focus on top of all nature of, erm, nature sounds.
At the time, I was in Newcastle-Upon-Tyne, far away from London, and the best way to listen to it for me was to wire my record deck up to my old bass amp, turn the bass on full and put the speaker against the edge of my full to the brim bath. I would then climb in and don a pair of headphones, close the curtains and take the trip to a new aural galaxy. Probably very dangerous, but new-age ambient floatation tanks were still a couple of years off, and my budget version did the trick just fine.
David Toop's book "Ocean Of Sound" is a great book that's well worth getting hold of. It looks at the history of ambient music from Debbusy and Eric Satie in 1889 right through to the late 1990's. You can get it here.
(click here to buy the first Orb album from Amazon UK)