Anyone who witnessed the performance of innovative four-piece Finnish group Gjallarhorn (pron.: “YAHlerhorn”) at the recent WorldFest in Grass Valley undoubtedly remembers the impossibly high, eerie vocals of singer Jenny Wilhelms and the very, very low, vibrating sounds of Göran Månsson’s huge sub-contrabass recorder. The counterpoint between Wilhelm’s very high and Månsson’s very low sounds, along with Adrian Jones’ viola and mandola and Petter Berndalen’s unusual effects-heavy drum kit, made for a memorable show. Gjallarhorn’s performance of ancient traditional Nordic music spun with trippy futuristic touches like delay on Wilhelms’ ethereal voice, and close dissonant harmonies between Wilhelms and Månsson’s flute, are showcased on Rimfaxe, named after the horse of the goddess of night and dawn in Nordic mythology. “iVall,” an improvisation on Scandinavian “cow calling” featuring Wilhelms doing her crazy-high vocals, is particularly interesting.