Two amazing master musicians, Chris Thile (mandolin) and Edgar Meyer (double bass) have been playing together for some 15 years, and began sporadic tours together in 2003, releasing a wonderful instrumental duets album, Edgar Meyer & Chris Thile, in 2008 and a collaboration with cellist Yo-Yo Ma and fiddler Stuart Duncan, Goat Rodeo Sessions, in 2011, and Meyer produced Thile's 2013 album of Bach compositions, Sonatas & Partitas, Vol. 1. They know each other well, and the fascinating communication that passes between them when they play is breathtaking, beautiful, and elegantly graceful, a cascading river of seamless musical notes that hits all the pockets, even if the pockets seem unlikely sometimes. This set finds them together again on ten new co-writes, and it's exactly what one might expect from these two virtuoso musicians, a genre-defying blend of folk, classical, jazz, and whatever else the two feel like quoting in a few quick, deft notes. A few cuts here find Meyer playing piano and Thile playing guitar, but the basic connection these two have forged over the years is never lost. Track after track, Meyer and Thile talk back and forth with their instruments, answering, questioning, one-upping, and in general, engaging in a wonderfully joyous dialogue that one hopes will never truly end. Both have been deemed musical geniuses by the MacArthur Foundation, after all. On Bass & Mandolin, they show why once again.