THE MUSIC MAKER

Once you know what you’re listening for, it’s easy to identify Rostam Batmanglij’s fingerprints on a song. The former keyboardist for the alt-rock band Vampire Weekend is now a producer who has worked with artists including Solange, Frank Ocean, and Kid Cudi. Batmanglij infuses his penchant for uncommon chord progressions and classical music into every album he touches. The result is fully realized, often startling pop, from Carly Rae Jepsen’s heady