California in the mid-sixties was all about psychedelia, but the Nitty Gritty Dirt Band were not having any of that: they were country through and through, and their 1972 breakthrough album Will The Circle Be Unbroken features old-timers Doc Watson, Maybelle Carter, Earl Scruggs and Merle Travis as special guests, bringing their ability together with the great chops and powerful playing of NGDB guitarist / singer Jeff Hanna.