Shimmering wind chimes, pulse-quickening pianos, glossy synths that radiate like sunbeams reflecting on ice—these are just a few of the soft-rock signatures that producer David Foster revolutionized on monster ballads for the likes of Chicago and Céline Dion. But his Midas touch isn’t confined to adult-contemporary pop: The Canadian maestro has also gilded classics for such R&B titans as Earth, Wind & Fire; Michael Jackson; and Brandy.