For a group that began in the '60s playing jug-band music, unplugging isn't really much of a gamble, so it's not surprising that the Nitty Gritty Dirt Band's laid-back sound is unaffected by their wooden instrumentation in Acoustic. They're always competent, with shimmering three-part harmonies and stellar musicianship, but that doesn't compensate for their generally forgettable songwriting. C

