Incendiary American roots duo Billy Strings & Don Julin tap into the vein of the earliest bluegrass music on their new album Fiddle Tune X, back when bluegrass was a rough-and-tumble art form pouring out of the Appalachian mountains, made with great virtuosity and huge attitude. With just two instruments (guitar and mandolin) and one voice, this duo has been tearing up stages across America and generating huge buzz based on their intense live shows.