Kraftwerk built upon the international success of Autobahn by expanding their conceptual conceits to an album-length exploration of radio waves (and the band's other favorite wavelengths of the electromagnetic spectrum). Musically, the album represents a quantum leap of pop sensibility; though still distinctly a "prog" soundscape, its brilliant melodic hooks (best represented by the title track and "Airwaves") are organized in more traditional--read shorter--form. In tracks such as the minimalist audio-verite "News," Kraftwerk pay homage to another of their musical influences, the great modern composer/theorist Karlheinz Stockhausen. "Antenna" foreshadows the techno-gods they became, with its electronic washes and clever less-is-too-much lyrics, which read, in total: "I'm the antenna catching vibrations; you're the transmitter, give information!" Radio-Activity is an underrated masterpiece waiting to be rediscovered.