Combining no-wave din and avant-garde leanings with punk intensity and an unlikely fondness for classic rock, Sonic Youth laid the groundwork for some of the biggest alternative rock bands of the '90s—a decade in which they, too, would become icons. They helped Nirvana get signed to a major and paved the way for mixed-gender bands like Hole and Blonde Redhead. More than anything, their inventive tunings and all-encompassing feedback swirl trickled down into noise-besotted acts like Unwound, My Bloody Valentine, Liars and beyond.