Who were the progenitors of the “Seattle sound?” As Kurt Cobain once put it in an interview, the movement’s roots arguably extend back to the late 1970s, when Wipers — a raucous punk rock cohort from Portland — began thrashing and released their unflinching debut Is This Real?. A chronicle of doomed figures, extraterrestrial presences, and alternate realities, it influenced a generation-plus of agitators with a proclivity for guttural vocals and deranged guitars.