Over and over and over, like monkeys with miniature cymbals, the joy of repetition really is in these hipster dance acts. The longer the oscillating piano riff of “All My Friends” drones on, the more intense it becomes, and the more you feel the weight of James Murphy recounting the end of his youth. Justice and Hot Chip use repetition more playfully, spotlighting their expertly sequenced sample chops as if they were guitar solos. Animal Collective makes the most of “My Girls’” three note arpeggio, opening it up to find a slippery, shapeshifting rhythm.