History of Silence (due Sept. 19) is the first new album from Icelandic outfit múm since 2013’s Smilewood. The new LP became something of a puzzle, taking two years to record, deconstruct, and put back together. The title hints at the album’s tone, but even though the songs are delicate, their color and boldness shines through. “Mild At Heart” reveals a carefully handpicked palette of electronic and analog sounds; an intricate introduction to the album. Immerse yourself in múm’s world when they play The Regent Theater on Thursday, Oct. 9.