Over three decades the Nighthawks have undergone a bewildering variety of personnel changes as they've traversed the nation playing blues and bluesy roots-rock, while taking time off to cut the periodic album. Last Train to Bluesville is something different from the usual: a purely acoustic disc that covers songs popularized in electric versions. ("Rollin' & Tumblin'" was originally "Roll & Tumble Blues," a traditional piece that songster Blind Willie Newbern recorded in 1929, but is far more familiar from Muddy Waters' propulsive 1950 cut that is the Nighthawks' inspiration.)

Besides some mid-century Chicago standards (Muddy's "Can't Be Satisfied" and "Nineteen Years Old," Sonny Boy Williamson II's "Mighty Long Time"), whose Delta flavors make country-blues treatments perfectly logical, the Nighthawks move into more unanticipated territory with "The Chicken & the Hawk," a Leiber/Stoller composition associated with big-band blues shouter Big Joe Turner, Chuck Berry's "Thirty Days" and -- most shockingly -- James Brown's "I'll Go Crazy."

While other blues artists have sometimes de-electrified blues standards, most of them have done it in a way intended to reassert the songs' rural references. Last Train has its more or less pure country-blues moments, and they're pleasurable ones. But overall, what the four members of the band in its present incarnation communicate is the feeling of electric music played on unamplified instruments, energetic and hard-driving, with some tasty jazz elements and hints of rock and rockabilly. They stick to the instruments you'd expect: guitar, harmonica, bass and drums; in other words no fiddle, mandolin or washboard to carry the music into the backwoods from which its ancestors came.

To no great surprise, the results are professional in the best sense. After all, these guys are veterans of stage and studio, steeped in the tradition and possessed of chops and spirit. Last Train rides to blues glory.