Released during a period of tense Cold War saber rattling, Tangerine Dream's Exit (1981) shows that even a machine-driven electronic band can claim a social conscience. Its first track, "Kiev Mission" (which the label misspelled on the album), opens with explosions, sirenlike wails, and then, against a stark sonic backdrop, a whispered plea (a female voice speaking Russian) to end the threat of a "limited" nuclear war, a genuine and much-discussed danger at the time. Some of the album's atmospheric pieces are a touch dated and static (though the X-Files-like "Remote Viewing" merits a thumbs-up). Still, Exit contains two of the most intriguing short-form compositions the group ever released: the driving "Choronzon" and the pulsing, ever-evolving "Network 23," a truly arresting piece in its day, and one that still sounds good a few decades later. --Terry Wood