A year after introducing Crescent City to the Celtic harp and Swedish nyckelharpa, Lisa Lynne and Aryeh Frankfurter will return with two new friends, allowing the community to explore musical styles from Ireland, Scotland, Appalachia and Scandinavia.

Lynne and Frankfurter teamed up with fiddler John Weed and guitarist Stuart Mason, members of the Celtic band Molly’s Revenge, to create the New World String Project. Now roughly two years old, the result has been a marriage of the Swedish and Nordic music Frankfurter and Lynne focus on with the Irish and Appalachian tunes Weed and Mason perform.

The two duos will bring this hybrid of music to St. Paul’s Episcopal Church in Crescent City on Tuesday.

“It’s definitely joyful, happy music. It’s a lot of fun with a lot of humor,” Lynne said. “There’s a chemistry that was natural right off the bat and for me personally it feels like being on an incredible sports team with incredible athletes, but they’re athletes of music being carried along (with) this strong powerful wave.”

Each bringing more than 20 years of musical experience to the table, Lynne and Frankfurter have performed together for about 12 years. Both play the Celtic harp. Lynne also plays the cittern, a stringed instrument dating back to the Renaissance, while Frankfurter plays the Swedish nyckelharpa, or keyed fiddle.

According to Lynne, much of the music she and Frankfurter perform are original pieces aimed at storytelling. She said she and Frankfurter tell a lot of personal anecdotes during their concerts.

Frankfurter noted since forming the New World String Project, the skill set each musician brings to the table keeps things spontaneous and exciting.

“We’re able to share our repertoire through the computer and sending files and listening,” he said. “And we have a couple of days where we get together and go over the material and bring together the set and repertoire, keeping it fresh and alive. What’s exciting is that the music has a sort of synergy and collaboration that is just really immediate and exciting and we have this sort of repartee between each other that makes it, I don’t know how to put it, joyful.”

Weed and Mason, who also plays a Greek stringed instrument similar to a mandolin called a bouzouki, have played together for about 16 years, joining Molly’s Revenge at about the same time.

Mason said it was relatively easy for the New World String Project to put together a repertoire because of the experience each duo brings to the table. During the show, in addition to performing as a quartet, there will be sections that showcase the musical styles of each duo, he said.

Though they are seasoned musicians, the collaboration between the two duos has been a challenge both Mason and Weed have relished. Weed, said playing with Frankfurter and Lynne, blending Irish, Scottish and Appalachian styles of music with Scandinavian styles, is about figuring out logistics like what key they’re playing in as well as determining if the character of the tune can be represented by an instrument that isn’t usually used in that style.

For example, Weed noted though Appalachian music isn’t intended for the nyckelharpa if a piece is written well it can transcend instruments.

“It’s just like if you played a Bob Marley song with a country band,” Weed said. “It’s still going to probably sound good because he wrote really good songs.”

However, Weed said the set of tunes he and his fellow musicians in the New World String Project play are carefully selected.

“There’s such a wealth of material out there that within a pretty short order of time we can find something that’s going to work,” he said. “That’s what’s been so exciting about this. I find it interesting to take old-time Appalachian tunes on a nyckelharpa. To me, it’s a delightful and really fun, cool thing to do.”

For Mason, being part of the New World String Project represents an evolution that started with an explosion in popularity of Irish and Scottish music in the U.S. about 20 years ago and is continuing now with a growth in the awareness of Scandinavian music.

“People are discovering what we call Scandi-trad,” Mason said, referring to Scandinavian traditional music. “Aryeh turned me onto it. When I heard him play his nyckelharpa I felt like I went through a doorway into a whole new world of Swedish traditional music the same way I went through the doorway 40 years ago for Irish music.”

Frankfurter said he hopes the New World String Project will give concertgoers a respite from their worries and concerns. The audience wants to connect with the musicians on stage and go on an adventure, he said.

“It’s a lot of joy, a lot of uplifting music and just tremendously exciting,” Frankfurter said. “Celtic music is different from Nordic music and all these styles come together to make people (go) through different landscapes from one song to the next.”

The New World String Project will play 7 p.m. Tuesday at St. Paul’s Episcopal Church, 220 E. Macken Ave., Crescent City. Suggested donations are $15 or $20 at the door. For more information, call 415-275-1466 or visit www.NewWorldStringProject.com.