Irish composer Donnacha Dennehy, whom, the New Yorker has called "a star of Dublin's active new music scene," makes his Nonesuch debut with Gra Agus Bas. This ambitious set features a pair of dramatic pieces written for two very different but equally extraordinary voices-former Afro-Celt Sound system vocalist Iarla O'Lionaird and American soprano, and Nonesuch label-mate, Dawn Upshaw. Often described as a post-minimalist, Dennehy, says British music magazine The Wire, "has a sound world all his own." Here he uses elements of Irish traditional culture as a springboard to create work with no visible roots-a borderless music that is mysterious and elegiac, as deeply moving as it is utterly transfixing.