Nelson says that music hasn't changed much in his lifetime.
"It's all music," Nelson says. "You got so many notes and there's so many words to throw in there, and you get different people mixing it up different ways. But you put it all together, and that's music."
Marsalis adds that the common ground between them makes playing together a natural fit.
"We're all part of the same root," Marsalis says. "It's like eating barbecue: Texas people barbecue; Louisiana people barbecue catfish. We taught them what to do with a catfish. We don't have to come together to do that, you know?
"All American root music is the same: We play shuffle rhythms, we play the blues, we have songs that we know. It was no strain for us, or to play with each other's songs on the album — all songs that I grew up hearing, of course. Willie is a part of that whole history."
"Its kinda like gettin' together more than coming together for the first time," Nelson adds. "We've always played basically the same."