Any time two greats who admire each other and are musically compatible team together, the results are usually mutually beneficial. That was true for Bill Monroe and Doc Watson, whose spirited union on this 17-song disc is a sampler of American musical styles. They ripped through bluegrass, folk, blues, spirituals, mountain tunes, work songs, reels and breakdowns. Monroe’s mandolin and Watson’s guitar playing were masterful, wondrous and performed without any trace of self-indulgence. Their vocals were also delivered with ease, fluidity and conviction, the product of two performers completely at ease with themselves and only interested in spotlighting the material. – Ron Wynn