In 1967, I was driving up to my college campus in Boca Raton, Florida, when a radio disc jockey from a Miami rock station played a record he'd brought back from L.A. The track was "Buy for Me the Rain," the first single from the Nitty Gritty Dirt Band's self-titled album, and hearing it that morning at dawn when the rising sun was just beginning to warm my left arm made me a lifelong Dirt Band fan.

It is hard to believe that the band has been out there for 50 years now. They've provided a soundtrack to my whole adult life and whether they were concentrating on folk, bluegrass, rock, country, Americana or a fusion of these elements, they have never disappointed.

This time out, to celebrate their 50th anniversary, they did a concert at the Ryman Auditorium, which served as the kickoff event for the annual conference of the Americana Association as well as a fundraiser for Public TV. The format relied on their Circle records, where they gathered together a world-class group of musicians and played and sang with them. On this one, we have Sam Bush, Jerry Douglas and Byron House filling out the band, with guest singers Vince Gill, John Prine, Allyson Kraus, Rodney Crowell, Jerry Jeff Walker and Jackson Browne.

An informal jam-like quality hangs over the production as the emphasis appears to be on having fun playing music with people the band has known all their lives. The overall tone is like homemade music, a back porch gathering where everyone is invited to hang out and listen; while they're having fun, the players are careful not to neglect their visitors -- audience pleasure is as important as their own happiness.

All of the musicians play songs they've been associated with over the years; Prine does "Paradise" and "Grandpa was a Carpenter,' while Browne gives us "These Days" and "Truthful Parson Browne" which he sang with the Dirt Band back in 1966. It's a night of memories but nothing sounds like it did originally; with Bush, Douglas and House supplementing the Dirt Band, you've got fresh arrangements and a steady drive.

Circlin' Back comes in two packages; the CD or the CD and a DVD of the concert. If you're thinking you don't need the album or the DVD because you saw the show on PBS, you might want to rethink that; both contain a lot of material that didn't make it onto the TV special.

What it boils down to if this: if you want to hear America's best Americana band doing what they do best under ideal circumstances, then you're going to hear this set. More than once.