Some bands take a few years to regroup for their next move; dream-pop pioneers Slowdive took 22, a return all the more bittersweet given how many bands their sound has influenced since. Combining the atmospherics of ambient music with rock ’n’ roll’s low center of gravity, Slowdive sounds as vital as anything the band recorded in the early ‘90s, whether it’s the foggy, countryish inflections of “No Longer Making Time” or the propulsive “Star Roving.”