David Z, Longtime Prince Associate and Key Architect of ‘the Minneapolis Sound,’ Dies at 78

David “Z” Rivkin, the Grammy-winning producer and musician who helmed Prince’s early demo tapes and engineered several of his albums, helped create Lipps Inc.’s 1980 smash “Funky Town,” and later worked with such artists like Fine Young Cannibals, the Jets and Jonny Lang, has died, his brother Bobby “Z” Rivkin (longtime drummer for Prince &…