Guitarist Fred Frith and saxophonist John Butcher have been key figures in free improvisation circles for decades, but The Natural Order is the first time the two Brits have recorded together. (This 2014 release captures a 2009 studio session that was mixed in 2012.) Both musicians are masters of extended technique, and at times, you might forget the actual sources (basically, guitar and sax) of the wild sounds you're hearing. The duo are always on the move, creating music that continually strikes out into new territory. Even though The Natural Order is divided into 10 tracks, it’s probably best listened to as a single exploration.