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THE artist formerly known as out of his mind appears to have stabilized.
When Prince "liberated" himself from the major-label music business a decade ago, his musical course became so bewilderingly indulgent that even the occasional bright spot wasn't much cause for celebration, since he'd likely be back soon with something unlistenable.
But here's a sign o' changing times: He's followed 2004's return-to-form album, "Musicology," with another R&B-rock hybrid that recalls the days when he tossed off these gems with effortless brilliance. Like its predecessor, "3121" (due in stores Tuesday) looks backward for its inspiration rather than blazing new trails, but its quirkiness, playful tone and rhythmic irresistibility remind you why Prince ruled the world for a while.