Singer-songwriter Kim Richey has always been a bit of a loose cannon on Nashville’s Music Row. Shying away from overproduced country pop, she keeps her songwriting polished, but not to the point where the songs become too slick to grasp. She aims for a simple, poignant grace in a way that brings to mind Lucinda Williams.

But on her new Rise — her first for the Mercury imprint Lost Highway and her fourth overall — Richey takes even bigger chances than she has in the past. Like Shelby Lynne, she’s moving away from any definable genre; there are elements of rock, blues, country, and jazz on the disc, but no style dominates. She’s too upbeat to fall under the loose umbrella that is "No Depression" alterna-country, yet she’s too sad and, well, alternative by Nashville’s standards to be mainstream. Rise found her working with producer Bill Bottrell, who cajoled hits from Sheryl Crow on her Tuesday Night Music Club and helped bring Lynne to prominence with I Am Shelby Lynne. But Richey’s sound is more eclectic than that of Crow or Lynne.

Her image is also unconventional for a Nashville recording artist. On stage at the House of Blues last Friday, playing a set drawn modestly from Rise, she looked more becoming in a loose ruffled blouse and jeans than some artists do in their designer gowns. And she maintained a relaxed pace with her laid-back attitude and lilting songs. "Every River," an alterna-country heartache tune off 1997’s Bitter Sweet, was followed by the mid-tempo march "Come Around," from 1999’s Glimmer. But it was her new material that was most appreciated. Backing away from the straight-ahead acoustic country music she favored on her first three albums, Rise branches out well beyond simple Southern accents.

The difference last Friday was most noticeable in two Eastern-tinged gems, "No Judges" and "This Love," the latter a rollicking shout-it-out number co-written by Chuck Prophet. And if Richey had little success in getting the cramped crowd grooving, she and her band still appeared at ease, smiling and cracking jokes to one another. The gentle contrast between the somber songs about traveling and heartache and the newer rootsy material may have caught some of her long-time fans off guard. But by the end of the set it was clear that Rise has been a big step forward for one of Nashville’s more formidable emerging singer-songwriters.