(Following a string of West Coast dates, the Mutual Admiration Society tour is heading east with upcoming shows in Minneapolis, Chicago, Cleveland, Boston and New York before closing Aug. 19 at the Birchmere in Alexandria, Va.)

As a member of Led Zeppelin, John Paul Jones became a rock star in one of the most successful, influential and, by many accounts, notorious bands in music history. Instead of projecting a rock star attitude, however, his voice conveys the personality of a journeyman musician who deeply loves his work and cherishes the opportunity to ply his craft as he sees fit.

The British musician is comfortable talking about his old band, but he has looked forward to his current role on tour with Nickel Creek and vocalist Glen Phillips, former lead vocalist for the rock band Toad the Wet Sprocket. The tour supports the release of Mutual Admiration Society, a collaboration between the Nickel Creek and Phillips. The tour also features drummer Pete Thomas, a member of Elvis Costello's band, the Attractions.

Even before signing up to play bass and mandolin on the tour, Jones had been showing up unexpectedly at acoustic concerts recently, including Jim Lauderdale's gig at a London club. Long attracted to acoustic instruments, Jones also immersed himself in the bluegrass and Americana sounds of MerleFest, a three-day event that took place in May in Wilkesboro, N.C.

In a phone conversation from his home near London, Jones told CMT.com he learned about MerleFest while searching the Internet for music festivals.

"I'd just finished a string of projects," he said a few days before returning to the U.S. for the Mutual Admiration Society tour. "I just thought it might be nice to attend something like MerleFest. Lo and behold, before I knew what I'd done, I'd booked tickets, flights, a cabin in the mountain, a car … as you can so easily. What really drew me to it was the lineup. I quite like the Americana aspect of it, as well as the bluegrass. There were so many good names, I just couldn't resist it."

Jones took his mandolin to North Carolina, "just in case," and played at a midnight jam session with Gillian Welch, David Rawlings and Nickel Creek mandolinist Chris Thile and fiddler Sara Watkins.

"There were mass mandolins and fiddles and banjos together at the end, and it was just wonderful," Jones said.

Did anyone in the audience have a clue regarding his identity?

"No," he laughed. "Pretty much no. Some of the musicians did at the end. … It was only when I went backstage, really, that the musicians got to know who I was." A few were shocked by his presence, although Jones noted, "Some people remembered that I did actually play mandolin with Led Zeppelin, so it wasn't quite so strange. I think they were surprised I was interested in bluegrass."

He'll forever be best known as a member of Led Zeppelin, although Jones was a successful studio musician in London long before anyone ever thought of "Whole Lotta Love" or "Stairway to Heaven." With versatility an essential trait of studio musicians, Jones was accustomed to playing several different styles of music on any given day.

"It wasn't like being in Nashville where it's mainly country or perhaps bluegrass sessions," he said. "It was literally everything from big band jazz to soul music to country music every day."

As a top session player during the British Invasion of the mid-to-late '60s, Jones still hears his early work on oldies radio stations.

"My arrangements keep popping up," he laughed. "It's quite nice. I wish I had a royalty on them, though. They were like $50 arrangements at the time. Things like 'Mellow Yellow' for Donovan … 'There's a Kind of Hush' and 'No Milk Today' for Herman's Hermits … 'To Sir With Love' with Lulu."

After Led Zeppelin disbanded in 1980, Jones worked as a record producer (working with Heart and vocalist Diamanda Galas, among others) and session work (including tracks with Paul McCartney). He released his first solo album, Zooma, in 1999 and another, Thunderthief, in 2001.

He was contemplating his next solo project when the offer was made to participate in the Mutual Admiration Society tour. Jones' introduction to Nickel Creek came after hearing mandolinist Adam Steffey's recordings with Alison Krauss & Union Station. An acquaintance told him if he enjoyed Steffey's playing, he should check out Thile's work in Nickel Creek.

Although Jones met the members of Nickel Creek during one of their European tours, he had actually only played with Thile and Watkins during the MerleFest jam session. As a musician still looking for new collaborators and challenges, he jumped at the chance to join the trio and Phillips on the Mutual Admiration Society tour.

"I couldn't resist it," he said. "It was too good to pass up. Nickel Creek are very fine musicians, and then I heard the record they did with Glen. He sings really nice, and I thought I should really be a part of this."

Jones' tenure in Led Zeppelin provided the level of income that has allowed him to pick and choose his projects during the past two decades. However, his early studio career had been lucrative, too.

"I actually was just about financially secure before Zeppelin, which allowed me to leave the studio world," he said. "Everyone thought I was crazy to join a band."

When Led Zeppelin was formed in 1969, Jimmy Page was best known as the guy who followed Eric Clapton and Jeff Beck as the Yardbirds' lead guitarist. Few people had ever heard of vocalist Robert Plant or drummer John Bonham.

"My friends really thought I was crazy," Jones said. "To be a studio musician in a big city was considered the height of the career, really, as a musician. … I was just doing so much work, though, I was going crazy. In fact, my wife saw in one of the music papers that Jimmy was forming a band, and she made me call him. And the rest is history."

But was the history as wild as we've all heard?

"It had its moments, I have to say," he laughed. "It was never dull. We had a good time. It was a good band, apart from anything else. That was the best part onstage."

Jones last toured in 2001 on a series of double headlined shows with the progressive rock band, King Crimson. He agreed to the tour with Nickel Creek and Phillips knowing it wouldn't be an extravagant, high-dollar venture.

"It is in a bus," he pointed out. "We don't get to use the private plane anymore."

Does Jones miss the days of touring in a private plane?

"Well, I do have to say, all pretensions aside, it is the way to tour," he chuckled. "No doubt about it."

Referring to the Mutual Admiration Society tour, he quickly added, "But I'm sure it will be a nice bus."