Tin Hat, formerly the Tin Hat Trio, is an acoustic chamber music group currently based in San Francisco. Their music combines many genres of music including southern blues, bluegrass, neoclassical, eastern European folk music, and avant-garde.Since its formation in 1997, the original Tin Hat Trio has often expanded its trio format by inviting other musicians to join them. All of their five CDs feature guests, among them Tom Waits and Willie Nelson, as well as friends like clarinetist Ben Goldbe