If any chamber group has the technical wherewithal to perform Brian Ferneyhough's complete works for string quartet and string trio, the Arditti Quartet surely takes pride of place. This three-CD package from Æon is a bracing survey of Ferneyhough's profoundly complex and challenging works, covering the Sonatas for string quartet (1967); the String Quartets Nos. 2-6 (1980-2010), with soprano Claron McFadden singing in the String Quartet No. 4; the Streichtrio (1994) and the String Trio (1995); Adagissimo (1983); Dum transisset I-IV (2006); and Exordium (2008). Ferneyhough is a proponent of the New Complexity, and uses ideas and strategies developed by the avant-garde in the late 20th century, including intuitive procedures that employ the total chromatic without strict observance of rows or other series. The music is uncompromisingly intense, angular, and fragmented in the extreme, and its myriad difficulties aren't disguised or softened. The Arditti Quartet specializes in such cutting-edge music, and they are at their best in works that stretch the boundaries of expression and technique. This set is recommended for adventurous listeners and serious students of Ferneyhough's work.