In much of the music world, personnel changes can spell the end of a band's career.
Even if a group survives a change in a key member, there's no guarantee fans will accept the new lineup. Just ask Van Halen about Gary Cherone.
In the world of Celtic Woman, however, which this winter welcomes Susan McFadden, change may actually be an asset. McFadden is the ninth singer to join the all-woman ensemble.
"I think when people come along to see us, they know that Celtic Woman has new faces all the time," said Chloe Agnew, one of two remaining original members of the Irish-accented vocal group in a recent phone interview.
"It's ever-changing. It's ever fresh. It's ever new," she said. "And I think some people are still glad to see that there are two originals left — myself and (violinist) Mairead (Nesbitt). That's a huge part of Celtic Woman: embracing the new combined with the old."
Agnew said being able to change and evolve as new members come and go may be the thing that enables Celtic Woman to have a far longer life than many other musical acts.
"I hope in that way, with that in mind, that will allow Celtic Woman to live on for many years," she said. "It's about four Irish women, it's about feeling kind of self-empowered and about bringing that to people all over the world."
The group will perform at the Citi Performing Arts Center Wang Theatre in Boston next weekend, March 9 and March 10 at 8 p.m. They will then travel to New Hampshire to play at the Verizon Wireless Arena on March 16 at 7:30 p.m.
Celtic Woman originally was created for a television special filmed in Ireland. Musical director David Downes and producer Sharon Bowne essentially recruited the four singers — Orla Fallon, Agnew, Lisa Kelly and Meav Ni Mhaolchatha, along with fiddle player Nesbitt — to perform that single concert.
Instead, PBS picked up the film of that performance, and it became a popular fundraising program for spring and summer 2005. This helped pave the way for the release of the show as a concert DVD that sold more than a million copies.
Meanwhile, the group's self-titled first studio album topped "Billboard" magazine's world music chart for a record-setting 68 consecutive weeks. Since, the group has released two more CD/DVD packages of new material, as well as a 2008 best-of CD and DVD, both titled "The Greatest Journey: Essential Collection."
In all, Celtic Woman has sold more than 6 million copies of its CDs and DVDs and has topped 2 million in tour ticket sales.
This success has been sustained even with somewhat constantly rotating parts: Fallon and Mhaolchatha left; singers Alex Sharpe, Lynn Hilary and Haley Westenra arrived and departed. Now, Kelly, who is expecting a child, has stepped away, and McFadden has joined Agnew and Lisa Lambe (who joined Celtic Woman last year) as the singers in the group.
Kelly, though, was still on board for the newest Celtic Woman project, "Believe," released Jan. 24. It's a dual release, with a concert DVD capturing the live debut of the "Believe" material when it was performed last fall at Atlanta's Fox Theatre. There's also a CD featuring studio versions of the new songs.
Agnew said the "Believe" project offers something fresh for Celtic Woman fans.
"I think with this particular studio album, when you compare it to our last studio album, (2010's) 'Songs From The Heart,' a lot of the material that was chosen for 'Songs From The Heart' were songs that were very special to us and they were songs that came from the heart," she said. "I think with 'Believe,' we decided to choose music that would inspire. It can be a very stressful and troubled world we live in right now. I think the idea behind 'Believe' was choosing music that would inspire a little bit of hope and a bit of faith in these troubled times."
Audiences can expect the Celtic Woman concert this year to feature many elements of the concert that was filmed for the "Believe" DVD.
"The set is quite similar: the lights, the costumes. It's all pretty similar to what you see on the DVD," Agnew said. "So, it's great to have those elements that people know.