Two-time Grammy award-winning jazz singer-songwriter Gregory Porter headlines the third annual Jazz Spectacular at Michigan Lottery Amphitheatre at Freedom Hill in Sterling Heights on June 16.Tickets went on sale over the weekend for the Jazz Spectacular that also includes Paul Taylor, Michael Lington, Kenny Lattimore, Avery Sunshine, Jean Carne, Roy Ayers, Ronnie Laws, and Lonnie Liston Smith.