Such music has many names: ambient, new age, contemporary instrumental, experimental, spacerock, chillout, ambient techno, ambient trance, mood music, world music, new acoustic music. The protests of some musicians and A&R people notwithstanding, I believe one of these names in particular - ambient - is a perfectly useful signpost for the phenomenon. It points to music across a hugely diverse spectrum: from the gorgeous solo guitar of John Fahey to the environmental techno of Biosphere; from the minimal avant-pop of The Penguin Cafe Orchestra to the chilled-out Celtic ambience of Enya and her clones.

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