The central theme of the new album from Third Seven is made plain in its title: “Cascadia.”

In a phone interview earlier this week, Billy Mickelson — longtime local experimental musician and the man behind Third Seven for the past decade — explained in slightly more detail.

“It’s an album about what home is to me … and following your heart to share home with the world,” he said from his parents’ place in Lincoln City. “Oregon is my home, and as anybody who lives here knows, that feeling you get from the mountains and the trees here, you can’t replace that with city life or anywhere else that you’d want to move.

“It’s really special to me,” he continued, “and I wanted to capture that in this album in a sentimental way.”

Right about there, however, is where easy interpretation ends. As has been the case with most of Mickelson’s musical projects over the years, “Cascadia” is a dense, dark forest of sound, powered primarily by his resonant cello and adorned here and there by piano, voice, unconventional percussion and whatever other sounds seemed right at the time. (In keeping with the theme, Mickelson’s brother Eliot, mother Florene and father Dean all perform on the album, as do a host of other friends and collaborators.)

There are songs with a dusty Western-noir feel and some that are influenced by Eastern European sounds. Mournful ballads sit alongside huge, heartfelt crescendos, and dissonance builds out of elegant, modern classical music. Some numbers grow into heavy, lumbering slabs of quasi-metal, no surprise to anyone who remembers Mickelson’s time in local prog-thrash band Mr. Potato. (“I’m a total metalhead,” he said.)

Throughout, Mickelson makes liberal use of the cello’s beautiful timbre, which can bubble and throb percussively one moment and turn an elongated drone into deeply textured, meditative music the next.

Mickelson recorded “Cascadia” mostly in his parents’ guest room, and he made it available for free download Tuesday on his website, www.thirdseven.com. He’ll celebrate its release with a show Saturday night in Bend (see “If you go”).

That show will double as a 10th birthday party for Third Seven, which Mickelson started when he was a student at Redmond High School. And it will triple as a farewell, at least for now; on Monday, he’ll leave on a tour that will take him to Europe for a second time before returning to crisscross the United States for two months.

After Saturday, Mickelson’s next Bend show is scheduled for Feb. 20.

“I love to travel, and … I want to share my music with as many people as possible,” he said. “To make a living, it’s hard to stay in one place playing music.”

The first Third Seven European tour, last January, took Mickelson — who’s on the road constantly and books all his own shows — to a wide array of performance spaces, he said.

“I played a lot of restaurants and bars, and punk-rock shows in squats,” Mickelson said. “It was a bunch of very, very diverse venues and very diverse people, but everyone was very kind and generous, and they love music and they love the efforts of somebody traveling that far to share.”

And that was just the evenings. Mickelson also wanted an outlet to play more ambient music, a la his recorded work with Strange Attractor and Mysle. So, he found a way to do just that.

“You can’t really do (ambient music) in a bar,” he said, “so … I perform cello for yoga in the mornings, where I just play ambient cello and loop the sound.

“(That kind of music) is still a big part of my life,” he said. “I definitely express that every day, which is really important to me, and I’m grateful for that.”

If it all sounds like a happy, if unlikely and unusual dream — traveling around the world DIY-style, playing for people who apparently are not only open to experimental music, but embrace it — well, it kind of is. But it’s not one that happened without a significant amount of effort on Mickelson’s part.

“This has just kind of evolved into something that everybody can appreciate. Something that’s really cool about Third Seven songs is I play every genre of show there is,” he said. “I play punk shows. I play metal shows. I play hip-hop shows. I play bluegrass shows. And all of it works, and it goes well with any audience, and that’s really special to me to know that I’ve found a format that does work for almost any person.”

He continued: “It’s not that I’ve made my sound the way it is just because I want people to like it. If they don’t like it, they don’t like it. But it’s from the heart and it’s sincere and it’s also palatable to others, and that’s a cool balance that I’ve struck just naturally.”

In fact, gaining the appreciation of listeners is not Mickelson’s biggest hurdle in sharing his music. His biggest hurdle is himself.

“It’s been a lot of work and it’s a huge challenge, because for me, I’m not really comfortable with selling myself,” he said. “I’m not a salesman. I can’t say, ‘I’m awesome. Book this show.’ So I just be myself and so far, so good.”

If you go

What: Third Seven album release, with The Horde and The Harem, Tom VandenAvond and Strange Attractor

When: 8 p.m. Saturday

Where: The Horned Hand, 507 N.W. Colorado Ave., Bend

Cost: $5

Contact: www.thirdseven.com