David “Z” Rivkin, a Grammy-winning producer and one of the architects of the “Minneapolis Sound,” has died at the age of 78. His brother Bobby Z, drummer for Prince and the Revolution, confirmed his death to the Minnesota Star Tribune. As Rivkin listened to Prince’s demo tape, the producer hummed a horn line alongside the music. After Rivkin worked with Prince on the demo, the legendary singer signed a contract with Warner Bros. and would work with the producer on multiple other projects. When discussing the Minneapolis Sound with the Star Tribune in the mid-Eighties, Rivkin called it “the sound of ignorance.”