These days, folk singers tend to tart up their arrangements under the assumption that the simple combination of voice and guitar puts too many people in mind of Boy Scout jamborees or other similarly traumatizing experiences. But not Ms. Negro, whose latest sticks to singing and strumming. The tack's not without risks, and at times, the overall sameyness causes the pace to flag. But Negro's crooning is crisp and sharp, helping her melodies transcend their familiarity, and she's capable of some sharp lines, like "Tell me how you fucked up and it's all her fault," from "Same As It Ever Was (Truly)," not to mention the wit displayed throughout "Your Bob Dylan." Silos & Smokestacks is uncut stuff, and when it works, the purity's invigorating.