Taking inspiration from the more extreme ends of guitar music, namely early-hardcore, dissonant no-wave, and a performance ethic that saw nothing wrong with playing the same note of feedback for half an hour, Sonic Youth were the Velvet Underground for the materialistic, hollow 80s. Where Pixies still tried to operate within the structure of rock and roll, Sonic Youth cast aside any convention. Essential releases include 1988's 'Daydream Nation' (probably their most cohesive), while 'Dirty' in 1992 remains their most pop, if such an adjective can be used in a description of Sonic Youth. They were progressive, wilfully intense, and though most famous members Kim Gordon and Thurston Moore are both over 50, their last album, 2004's 'Sonic Nurse', was their most difficult in ages. Architects of grunge, guaranteed to challenge.