Rich with imagery of intimate child- hood moments that range from bewitching to chilling to flat-out perplexing, The Silver Gymnasium is Okkervil River frontman Will Sheff’s autobiographical essay on growing up in small-town New Hampshire, circa 1983. Ordinary occurrences become otherworldly events on the jaunty “It Was My Season” and lush “On A Balcony.” Simple conversations become free associations that speak of nursemaids, blank pages and songs taped from the radio. Producer John Agnello imbues each cut with a musical Instagram, tinting the instruments with a shimmer of synths and painting Sheff ’s voice with the gauzy shade of bluish gray. The stories that he tells are never quite clear, leaving the listener responsible for cracking the code, a brilliant approach that mirrors the fuzziness of the memories themselves.