This is the first of four tracks on Brian Eno's rather unusual album, Ambient 1: Music for Airports, the first album by any artist to be explicitly labeled "Ambient music." It was intended as a sound installation to calm people's nerves at airports, after Eno spent time at Cologne Bonn Airport in Germany and found the piped-in music to be "nervous" and "tingly." The album was briefly installed at LaGuardia Airport in New York in 1980.
In an interview with Complete Music magazine in 1982, Eno referred to his ambient output as "bisexual." He points out that there is a "correspondence between raspiness in voice and male dominance in society," and that he'd been moving away from coarse vocals to choral voices.
Eno used a series of tape loops to create these sounds. "A whole series of very long tape loops, like 50, 60, 70 feet long," he told Interview magazine in 1978. There were 22 loops. One loop had just one piano note on it. Another one would have two piano notes. Another one would have a group of girls singing one note, sustaining it for 10 seconds. There are eight loops of girls' voices, and about 14 loops of piano. I just set all of these loops running and let them configure in whichever way they wanted to, and in fact the result is very, very nice."