The bombastic industrial rock and abject, tortured persona of Nine Inch Nails frontman Trent Reznor helped a lot of young people find catharsis throughout the â90sâor to revel in their own downward spirals. This millennium, Reznor has muted the overwrought anger and self-loathing and created some cerebral electronic music that proves his championing of Autechre wasnât a pose. NINâs first album in five years, Hesitation Marks, finds him mellowing into a nervy producer of white-knuckle techno rock. âCame Back Haunted,â indeed. (KeyArena, Seattle Center, keyarena.com, 8 pm, $65â$571, all ages)