The Bothy Band meets the Flecktones in Lunasa, Ireland’s new all-starquartet. Like the late, lamented Bothy Band, Lunasa emphasizes flute,fiddle and pipes in it’s dazzling reworkings of traditional Irish folktunes. As Bela Fleck’s Flecktones have with bluegrass, Lunasa managesto marry jazz-rock bass lines and an expanded harmonic sensibility to anolder rural music. The impressive results can be found on theall-instrumental albumn, “Otherworld,” Lunasa’s first U.S. release.The band’s key member is Trevor Hutchinson, who plays double bass, aninstrument rarely seen in Irish folk music. But his vigorous bowing andplucking make the underlying rhythms in these jigs and reels moremuscular and obvious than ever before. Hutchinson played in the rockband the Waterboys before joining rhythm guitarist Donogh Hennessey inthe Sharon Shannon Band. That band’s experiments in beefing up thebottom of Irish folk music have been taken a step further in Lunasa,where Hutchinson and Hennessey are joined by flutist Kevin Crawford ofMoving Cloud and All-Ireland fiddler and tin whistler Sean Smyth.The quartet always tours with a guest piper, and Mike McGoldrick andJohn McSherry handle the pipe parts on the new album. Even on suchtraditional tunes as “Lafferty’s,” the bass, fiddle, flute, guitar, andpipes build a rumbling momentum as if determined to drag Irish folkmusic kicking and screaming into the 21st century.