"Atmospheres" exemplifies much of Ligeti's theory suspending harmony in favor of sustained sounds. The piece opens with a "fully chromatic cluster covering more than five octaves, held by strings and soft woodwinds", out of which various groups of instruments drop out successively, followed by various "strands of sonic fabric" reenter the composition, first white notes then black notes along with shifts in timbre and duration of notes that drive the piece forward. Consequently, Griffiths writes, "the whole piece is a study in what Ligeti's essay had called the 'permeability' of musical structures, how some will mix with a great many others, some stand always apart; it is also a demonstration of what can be achieved when all the usual regulators, being so finely tuned at the time by other composers, are left open."