Reigning “The Voice” champ Niall Horan is back with John Legend, Gwen Stefani and new coach Reba McEntire for Season 24 of “The Voice.” “Extra’s” Melvin Robert sits down with the group to dish on what’s in store for the new season — which is the first without Blake Shelton — and the dynamics among the coaches. “The Voice” premieres September 25 on NBC.