A folk outfit out of Bristol, England, Spiro isn't one's garden-variety folk group, sounding more like a classical chamber quartet playing traditional material with Pentangle, Steve Reich, and Philip Glass all sitting in, and the result, when Spiro is at its best, is a startling and fresh spin on the whole British folk tradition. The group grew out of the Bristol folk scene in 1993, and released an album on Uncle Records, Lost in Fishponds, under the name the Famous Five in 1994. After stabilizing the lineup (Jane Harbour on violin and viola, Alex Vann on mandolin, Jason Spark...