The last time guitar virtuoso Ben Harper was in Spokane, it was summer 2005, the Knitting Factory was still known as the Big Easy and Harper had most recently released his gospel album There Will Be a Light. A dozen years later, Harper is headed back to the Knit with his ace backing band the Innocent Criminals, and he’s touring behind last year’s Call It What It Is. But not much has changed in terms of Harper’s style, a vivid blend of old-school blues, classic rock ’n’ roll, folk, reggae, soul and the sensibilities of every jammer from the Allman Brothers to Dave Matthews. And Harper is still a generous bandleader, giving all of his musicians — and even his audiences — a chance to take part in his deep catalog of songs.