If you associate the North Wind only with cold air, open your ears. Le Vent du Nord, the four-man vanguard of the Québec folk scene, offers the sounds of melodeon and hurdy-gurdy, assorted strings (violin, bouzouki, guitar), rhythmic foot-stomping and stirring vocal harmonies. Têtu (Headstrong), the band’s eighth album, is a dazzling 15-track collection of original and traditional songs at turns rollicking and sad, fanciful and forlorn