Rock’s most famous chameleon has changed personas countless times during his career, from Ziggy Stardust to the Thin White Duke. With each mask comes a new sound. For his 25th album, Blackstar (stylized as a symbol), the icon threw out the rulebook. His longtime producer, Tony Visconti, says the goal was to avoid rock ’n’ roll and create a new fusion sound. Released to coincide with the singer-actor’s 69th birthday, the seven-song album includes the unsettling title track, a shape-shifting, apocalyptic torch song that runs nearly 10 minutes, and “Lazarus,” the horn-drenched title number from Bowie's current off-Broadway musical, based on The Man Who Fell to Earth (he starred in the 1976 film adaptation). Trippy, jazz-infused art rock would be one way to describe the album. There are hip-hop beats on one track and words taken from the sci-fi classic A Clockwork Orange on another. It’s not easy listening, but the artist has always challenged norms and changed the pop music landscape in the process.