“We’re going to share some wisdom gleaned over the last 20 years,” promised Low’s Alan Sparhawk to a transfixed Metro crowd. “But just some.” And Low delivered, entrancing the audience with a set that included highlights spanning their double-decade catalog as well as tracks from new album The Invisible Way, which features drummer/vocalist Mimi Parker singing lead on a number of songs. From behind the kit, Parker alternated lead vocal duties with Sparhawk as the pair sprinkled harmonious incantations into the air throughout their soul-cleansing set. Calm on the surface, Low’s expert treatment of swelling tension rendered each brush of the cymbals as visceral an experience as the eventual thunderous guitar eruptions that followed. The night was capped by watching Sparhawk take teeth to guitar strings during “Pissing” as Low proved once and for all, if you’re gonna call them anything, don’t call them slowcore.