It's hard to find Janet Jackson in the beginning of Discipline, or at least a Janet Jackson to use as a measure among all the others. The album's first song, a slight digital jam called "Feedback," hides her in a mess of uncertain vocal tones and incongruous lines about guitars. (It's like one of those Rolling Stone covers with a pop star holding a guitar for no apparent reason.) "Rollercoaster" flits through another series of simmering beats and different vocal styles, most of them too generic to identify with a personality—much less that of the most commanding Jackson.
Then Discipline gets good and stays that way, more or less, until the end. The change arrives with "Rock With U," the kind of banging club track that Jackson at her best has come to own: With bigger beats to counter, she drapes her voice over wide spaces below and lays it out in all its diaphanous glory. It's a habit she continues and carries out just as forcibly in ballads, as in "Can't B Good," a majestic song produced by Ne-Yo, with an ear for those classic Jackson-family quivers and trills. Janet's quivers in particular have always been the most compelling for the way they suggest a kind of sensual embrace of conflict and pain, and they come to dominate Discipline in the end. She also sings about masochistic sex a lot, but that's just a distraction.