Codeine’s April reunion gig at the Sunset made their 18-year absence seem irrelevant. The slowcore legends hadn’t lost an iota of their methodical, emotionally fraught power. Stephen Immerwahr’s voice still possessed that woebegone “lost my record collection in a flood” tone, and the group executed their taut, slow-motion dynamics with staggering precision. Touring in support of their new box set, When I See the Sun, Codeine return to unleash with stoic grandeur one of rock’s most poignant catalogs. (Triple Door, 216 Union St, www.tripledoor.com, 8 pm, $15 adv/$18 DOS, all ages)