A wide range of artists will gather to celebrate what would have been Johnny Cash’s 80th birthday at a concert to take place on April 20 in Austin, TX. Kris Kristofferson, Lucinda Williams, new troubadour Ray LaMontagne, Soundgarden singer Chris Cornell, country superstars Kenny Chesney and Ronnie Dunn and current country rebel Jamey Johnson are among those who have agreed to participate at the tribute show dubbed Walk the Line: A Celebration of the Music of Johnny Cash.