The Chieftains and Paolo Nutini

Bobby McFerrin, Gavin DeGraw, Salif Keita, Paul Young, Siedah Garrett, The Commodores, Sergio Mendes, Mickey Thomas, Toto, Wang Chung, Lou Bega, Matt Sorum, Peter Wolf, Dave Koz, Go West, Jens Lindemann, Michelle Wolf, Vinnie Colaiuta, The BossHoss, Bijou, Christina Stürmer, Udo Lindenberg, Alphonso Johnson, Gracinha Leporace, Erika Heynatz and Thomas

Brad Paisley and Mat Kearney

Allen Toussaint, Gregg Allman, Joan Osborne, Garth Hudson, Joe Walsh, John Hiatt, John Mayer, John Prine, Jorma Kaukonen, Larry Campbell, Lucinda Williams, Jakob Dylan, Marc Cohn, Mavis Staples, Teresa Williams, Eric Church, The Levon Helm Band, Justin Guip, Byron Isaacs, G. E. Smith, Roger Waters, Warren Haynes, Bruce Hornsby, My Morning Jacket, Grace Potter, Amy Helm, Barry Mitterhoff, Robert Randolph, Ray Lamontagne, David Bromberg and Dierks Bentley

Trace Adkins and Colbie Caillat

John Ondrasik and Five For Fighting