“In ambient music, Eno often imitated or borrowed sounds from existing locations, and organised them in compositions to produce new environments. He often used tape loops of differing lengths played simultaneously so that their interaction randomly produced ‘sound events in periodic clusters’, in much the same way the sounds of frogs, insects and birds in a natural environment occasionally seem to express chords and melodies.” – Oblique Music – pg 90
“Eric Tamm has suggested that texture and timber may be off the essence in the ambient style, but a few general remarks may clarify the style’s use of rhythm and harmony’. He examined thirty ambient pieces, and found that eleven of these dispensed with pulse altogether, the rhythm consisting of a gentle ebb and flow of instrumental colours.”
Harmonically, Eno’s ambient pieces often use static or ambiguous harmonies, sometimes suggestive of chords but just as often consisting of nothing but a drone with… pitches drawn from a diatonic pitch set appearing and disappearing. — Two textural principles – layering and TIMBRAL HOMOGENEITY. These principles were combined so that a typical ambient piece by Eno was composed of 3 to 7 distinct timbral layers.