The Bristol sessions of 1927 have been called the "Big Bang of Country Music," as some music historians have considered them the beginning of the modern country music genre. The popularity of such musicians as the Carter Family, who first recorded at the sessions, proved to industry executives that there was a market for "mountain" or "hillbilly" music. Other influential 1920s-era location recording sessions in Appalachia were the Johnson City sessions and the Knoxville sessions. Early recorded country music (i.e., late 1920s and early 1930s) typically consisted of fiddle and banjo players and a predominant string band format, reflecting its Appalachian roots. Due in large part to the success of the Grand Ole Opry, the center of country music had shifted to Nashville by 1940. In subsequent decades, as the country music industry tried to move into the mainstream, musicians and industry executives sought to deemphasize the genre's Appalachian connections, most notably by dropping the term "hillbilly music" in favor of "country." In the late 1980s, artists such as Dolly Parton, Ricky Skaggs, and Dwight Yoakam helped to bring traditional Appalachian influences back to country music.