Steve Earle Emmylou Harris Hank Williams Sr. Lucinda Williams Bill Monroe The Carter Family Ralph Stanley Les Paul Gillian Welch Woody Guthrie Alison Krauss John Prine Dwight Yoakam Guy Clark Justin Townes Earle John Hiatt Levon Helm Willie Nelson Bob Wills Waylon Jennings Robert Earl Keen Roy Acuff Rick Danko Joe Ely Rodney Crowell Graham Parker Dave Edmunds Nick Lowe Lyle Lovett Mavericks James Mcmurtry George Jones Hayes Carll Ryan Adams Richard Thompson Gillian Welch And David Rawlings Bruce Springsteen The Band Dave Rawlings Machine Merle Haggard Bruce Cockburn Greg Brown Elvis Costello Billy Joe Shaver Joe Jackson John Hammond Rosanne Cash Jason Isbell And The 400 Unit David Olney