Star Rating: ****

When is a waltz not a waltz? When it's a polska played by a string quartet that's not a string quartet, at least not as we know 'em. Annbjorg Lien put this foursome together for the Telemark festival in her native Norway last year and, while it comprised two violins, viola and cello, the violins were the steely, sweet and sour-toned Haardanger fiddles, and occasionally the more customary model. The viola was a five-string version and banjo and guitar also featured.

Playing mostly Lien's compositions, Swedish violist Mikke Martin, Canadian cellist Christine Hanson and American multi-instrumentalist Bruce Molsky produced a stirringly different sound with its eerie high end and propulsive low notes regularly achieving the atmosphere the tune titles promised. The Old Car had a jalopy-like quality. Gossip captured the implied voices and Home East's mixture of viola harmonics and pizzicato cello and fiddle was suitably Oriental.

If the handful of original songs didn't find Molsky quite as comfortably downhome as he sounds on American folksongs, this became a small point as the instrumental material dominated. Molsky's assertion that old-time Appalachian music has as strong Norwegian roots as it does Scottish was backed with a raking hoedown with strong Nordic textures, and Hanson's Tennessee waltz section of her Cremation of Sam McGee suite took on an irresistibly bluesy hue.

Groups brought together in this way very often cease after the first gig. On this repeat outing, this one sounded like it was finding a groove that's going places.