“The good thing about this is that it did happen fast -- like the first one,” says Nitty Gritty Dirt Band member John McEuen, describing the evolution of Will the Circle Be Unbroken, Vol. III. “In April, the actual [record] dates were getting set. In May, we recorded for a few days. And then in June, we recorded for 10 [more]. And then it was done.”

The double album, which Capitol Records released Oct. 1, features 32 acts performing mostly traditional country songs with the Dirt Band. Besides McEuen, the band’s members are Jeff Hanna, Jimmy Ibbotson, Jimmie Fadden and Bob Carpenter.

The first Circle album, a groundbreaking collaboration between the Dirt Band and the royalty of country music, was recorded in 1971. Its sequel came out in 1989. Earlier this year, Capitol Records re-released the first Circle in a remastered and expanded format. It was this vote of confidence on the label’s part, says McEuen, that convinced the band it was time to do another one.

Underscoring that decision, McEuen adds, was the fact that audiences had been asking the band “every night for the past 15 years” when it was going to do another Circle album. “We didn’t know we had started a series,” he laughs. “It’s a nice thing -- go out and pick the cream of the crop every now and then.” Randy Scruggs, who produced the second Circle album and played on the first one, returned to co-produce Circle III with the band.

Once the Dirt Band decided to do the project, the next chore was picking the acts to participate. “It was very methodical, democratic anarchy,” McEuen explains. “Everybody had suggestions, and Randy listened to them all. On our list, we just put down those people that we thought were important for different reasons.” A few choices -- McEuen won’t specify which ones -- had to decline the offer to participate because of scheduling problems. “But had we gotten them, I don’t know what we would have done with them,” he observes, noting the overflow of talent.

“Jimmie Fadden had known [blues musician] Taj Mahal -- we all knew Taj Mahal -- from the L. A. days,” McEuen continues. “Having him on there was important because he goes back to our own circle of when we all started. Jimmy Ibbotson wanted to have Emmylou [Harris] there again. They’d sung together. I wanted Rodney Dillard. Jeff [Hanna] wanted to do a song with Willie [Nelson] and Alison [Krauss]. It’s funny. Halfway through it, somebody said, ‘Why haven’t we called Vince Gill?’ ‘We forgot.’ ‘So let’s call him.’ And 10 minutes later, he was confirmed.”

As befits such a torch-passing undertaking, there are a lot of father-and-son combinations on the new album. McEuen’s son Jonathan and Hanna’s son Jaime sing “The Lowlands” together, a song written by Earl Scruggs’ son (and Randy’s brother), Gary. The elder Scruggs, a centerpiece of the first two editions, is also featured on this latest one. Del McCoury performs with heirs Robbie and Ronnie. Jimmy Martin’s son, Ray, in on board. Doc Watson’s grandson, Richard, backs him on two cuts. Jokes McEuen, “We had to set it up so that in 20 years [all the sons] can do a Circle.”

Ailing Johnny Cash wrote and performed “Tears in the Holston River” especially for the album. While the band was more casual in its sessions with the other acts, McEuen says it was on its toes to accommodate Cash. “He didn’t need to sit there and have us learning his song. He was just finishing the lyrics, scratching it on paper, as he was coming into the studio. When Mr. Cash calls and says, ‘I’ve got a song that’s got to go on the Circle album about [Mother] Maybelle [Carter]. I’ll send you the chords. You boys be ready,’ then you get ready -- and we were. I’d say there were similar concerns when we recorded [the first Circle] with [Roy] Acuff -- except Cash didn’t tell us to get it right the first time.”

McEuen says he wanted to pay tribute on the album to the late Don Reno & Red Smiley, a bluegrass act whose importance he thinks has been overlooked in the current revival of interest in that form. This led to the inclusion of “Love, Please Come Home,” which the band performs with the McCourys.

Also featured on the album are Matraca Berg, Sam Bush, June Carter Cash, Vassar Clements, Iris Dement, Jerry Douglas, Glen Duncan, Josh Graves, Byron House, the Nashville Bluegrass Band, Tom Petty, Tony Rice, Ricky Skaggs, Glenn Worf and Dwight Yoakam.

All the recording sessions were filmed, McEuen reports: “Two or three cameras were shooting all the time. There’ll be a video coming out of it. We’re not sure what yet.”

Beyond the album itself, McEuen is excited about the spirit of the band, which he rejoined a year and a half ago after several years of pursuing solo efforts. “Not only is the timing right for Circle III in the [music] industry,” he asserts, “but also within the band and our abilities, it’s never been better. This is the best version of the group that’s ever been out there. People are coming to our shows that were followers from the ‘60s, the ‘70s, the ‘80s, the ‘90s. They’re out there in this audience all mixed together. We start one song and a fourth of the room claps, and the others go, ‘What are they making noise about.’ We start another song and a third of the room on the other side might go nuts. This is the band that wouldn’t go away.”

The Nitty Gritty Dirt Band appear on CMT Most Wanted Live this Friday (Oct. 18) at 7 p.m. ET/PT. During this weekend’s guest appearance on the Grand Ole Opry, the Dirt Band will be joined by Vince Gill, Alison Krauss, Iris DeMent, Earl and Randy Scruggs, and Del, Ronnie and Robbie McCoury. The performance will be featured on Grand Ole Opry Live, airing Saturday (Oct. 19) at 8 p.m. ET/PT on CMT.