Barry Manilow's nods to different strands of pop allow listeners to hear what ignites him. Whether he's going back to ‘50s dance-hall days on “Jump Shout Boogie,” luxuriating in disco strings on “New York City Rhythm,” or giving his chart counterparts from the ‘70s the cover treatment, his thoughtful takes on pop's many forms show him to be a scholar—and fan—of modern music.