Some Irish folk groups power along on their fiddles. On this, its eighth album, Lúnasa powers along on whistle and drone. The fiddle is there too, but it is outnumbered. The credits inside the cover list a single fiddler against tin whistle, flute, three sets of low whistles, and some uilleann pipes. In “Pontevedra to Carcarosa” the fiddle accepts its supplementary role and steps back, echoing and cushioning the blowing. The strummed strings simmer quickly. The mood is optimistic. Kevin Crawford’s “Tune for Dad” loves its subject. Lá Nua is brisk with reels—the album bubbles along with a near-constant skipping chuckle. It slows down for the softly fluted “Island Lake” and snaps into focus for “Tro Breizh”: a salute to another Celtic culture, the Breton. All bright, all fluid.