“2/1” uses six different vocal tracks, sung by Christa Fast, Christine Gomez, Inge Zeininger, and Eno himself. The tracks are cued at specific intervals designed to layer and cascade unpredictably. Eno explained the track in a 1996 talk given at Imagination Conference in San Fransisco:

Music for Airports, at least one of the pieces on there, is structurally very, very simple. There are sung notes, sung by three women and my self. One of the notes repeats every 23 ½ seconds. It is in fact a long loop running around a series of tubular aluminum chairs in Conny Plank’s studio. The next lowest loop repeats every 25 7/8 seconds or something like that. The third one every 29 15/16 seconds or something. What I mean is they all repeat in cycles that are called incommensurable – they are not likely to come back into sync again.

So this is the piece moving along in time. Your experience of the piece of course is a moment in time, there. So as the piece progresses, what you hear are the various clusterings and configurations of these six basic elements. The basic elements in that particular piece never change. They stay the same. But the piece does appear to have quite a lot of variety. In fact it’s about eight minutes long on that record, but I did have a thirty minute version which I would bore friends who would listen to it.