Though underwritten by the Country Music Hall of Fame and Museum in Nashville, this essential two-CD collection hardly contains a bar of country. It does, though, illustrate the influence of Nashville's music scene on the development of R&B from 1945 to 1970. The set includes familiar names like Little Richard, Ruth Brown and Etta James, who tears into Ray Charles's "What'd I Say." But most of the performers are less-heralded heroes like blues guitarist Johnny Jones. Fascinating liner notes complete this absorbing ride.