Now You Know, the first solo outing from Built to Spill frontman Doug Martsch, opens with “Offer,” a slide-blues workout in which the singer-guitarist identifies himself as “everyone/Someone used to love.” That’s kinda, sorta true. With BTS, Martsch has amassed a loyal following, moving steadily along the Amerindie career path from second-stage Lollapaloozer to the closest thing the movement’s had to a real-deal guitar god. Songwise, though, his band peaked early: 1997’s Perfect From Now On remains its high-water mark, a clutch of genuine mesmerizers top-heavy with guitar-rock shenanigans and Martsch’s tuneful, Neil Young-style warble. This time out, the axman mostly unplugs, downplaying Marshall-stack nirvana and even drums in favor of acoustic slide guitar and a shuffling, faux-waltz backbeat that sometimes seems more suggested than actually played. The end result is a sound that’s lean and seductive, half Mississippi Delta, half seriously inspired demo. The method places extra emphasis on the songs, of course, so it helps that the 11 collected here are Martsch’s best since back when he was Perfect. “Lift” is a deliciously warped pop tune with a guitar solo that slowly claws its way to the surface. “Gone” is a finger-picked roundelay powered by low-in-the-mix bongos. And “Window” cooks up a complete country-blues hootenanny in just under four minutes. More important, though, every time Martsch plugs back in, he sounds like a man rejuvenated. Electric foot-stompers such as the wiry “Sleeve” and the Meat Puppets-meet-Led Zeppelin “Instrumental” are mainly tossed-off diversions, but they still manage to raise expectations for the next Built to Spill opus. Here’s hoping that Martsch can still play well with others. —Shannon Zimmerman