Founded as Hespèrion XX by viol player and Catalan music director Jordi Savall in 1974, Hespèrion XXI has since become renowned for its magical albums exploring forgotten corners of traditional and classical music. Impossible to pigeonhole, the ensemble has brought us centuries-old dances from the New World, 400 years of Turkish music, the folk traditions of Sephardic Jews, and so many more inspired albums, each thrillingly performed and thoroughly researched.    The epic 2010 album The Forgotten Kingdom is one of Savall’s most inspired, an intoxicating tableau of songs and dances by medieval troubadours from across Europe. Savall and his musicians, including soprano Montserrat Figueras, create an unforgettable sense of theater in their exploration of music’s ancient roots.