Primary Wave has announced a partnership with the estate of Isaac Hayes to administer the late singer-songwriter-producer’s publishing interests. Additionally, the union will see Brookfield-backed Primary Wave market the name, image, and likeness of the longtime South Park voice actor Hayes, who released at least 20 studio albums as a solo act (1969’s Hot Buttered Soul chief among them) and penned well-known works including “Soul Man” and “Hold On, I’m Coming” during his decades-long career.