Chatham County Line are a band deeply in love with bluegrass, but they aren’t willing to be tied down by its traditions and conventions, and few groups have been as successful at fusing contemporary songwriting styles with the classic acoustic sound. IV — which, sure enough, is the group’s fourth album — is full of inspired picking from all four members (Dave Wilson on guitar, vocals and harmonica, John Teer on mandolin, fiddle, viola and vocals, Chandler Holt on banjo, guitar and vocals, and Greg Readling on upright bass, pedal steel guitar, piano, and vocals) though this band is more interested in serving the songs than in showing off blazing speed, and producer and engineer Chris Stamey brings a natural, live sound to the recordings that gives this music a warmth and presence akin to sitting in the room with the band. But as good as Chatham County Line are (and they’re very good indeed), what really sets this group apart is the strength of the songwriting; Wilson wrote or co-wrote all but three selections on IV, and he’s an intelligent and eloquent lyricist who can also conjure a strong melody, whether he’s celebrating some rowdy good times on “Let It Rock,” charting the path of a grown-up love affair on “One More Minute” or bitterly recalling the true story of an act of racist violence in 1963 in “Birmingham Jail.” Teer and Holt also wrote some songs for this set, and if they’re not as prolific, they show Wilson doesn’t have a monopoly on the talent in songcraft. The maturity and clear voice of Chatham County Line’s music has more in common with top-shelf singer/songwriter stuff than cookie-cutter bluegrass, and IV delivers some absorbing, contemplative food for thought along with plenty of great acoustic music; anyone who thinks Alison Krauss and Nickel Creek are setting the high-water mark for adventurous bluegrass should certainly give this album a listen. – Mark Deming