Sonic Youth made its first moves toward rock with EVOL, a stunningly fluent mixture of avant-garde instrumentation and subversions of rock & roll. The band benefits greatly from the addition of structure, which gives their aural experiments a firm grounding, but the addition of drummer Steve Shelley is essential to the group's new, dangerous edge. With the added propulsion, the fearless rush of "Expressway to Yr Skull" (a.k.a. "Madonna, Sean and Me") and the near-pop of "Green Light" are undeniably powerful, as are the eerie textures of "Shadow of a Doubt."