The notable artists on your television this week include: Bleachers (Kimmel; 4/17), Dreamcar (Kimmel; 4/18), Ed Sheeran (Fallon; 4/17), Alt-J (Fallon; 4/18), Bastille (Corden; 4/18), Car Seat Headrest (Conan; 4/18), John Mayer (Ellen; 4/17), Spoon (Ellen; 4/18), and Warpaint (Ellen; 4/20).