Control (1986) and Janet Jackson’s Rhythm Nation 1814 (1989) went far in wasting any lingering impression of their creator as merely Michael’s kid sis. Irrefutably the work of a woman of substance, “janet.” completes the makeover. Enlisting whiz producers Jimmy Jam and Terry Lewis for Control was Jackson’s first flash of brilliance; the duo fused hip-hop assertiveness and pop smarts to spark both the singer’s big-time explosion and a new persona; a sweetheart but a powerhouse, cute but no ingenue. “Janet.” deepens the groove. With 27 tracks (songs punctuated with sound effects, pillow talk and theatrical sound bites) and titles (“Throb,” “The Body That Loves You”) that spell out the album’s theme, this is Jackson’s erotic rite of passage. Collaborations with opera diva Kathleen Battle and Public Enemy’s Chuck D hint at the music’s allusiveness; from MOR balladry to Memphis soul, from house to jazz. In more versatile voice than ever, Jackson perches atop the rhythmic percolations; cool, not exactly calm, but collected.