In an age when most people under age 30 are more likely to own an iPod than a CD player, it’s unusual — and refreshing — to see a business buck the trend.

But that’s just what the Bull Moose Music chain has been doing. By establishing a one-on-one relationship with its customers and diversifying its inventory to include books, DVDs, collectibles and other items, it’s managed to not only survive as sales of physical CDs have steadily declined, it’s thrived. What began as a small store in Brunswick in 1989 now consists of 11 stores and more than 150 employees throughout Maine and New Hampshire.

On Saturday, Bull Moose will unveil a new, 6,200-square-feet addition in its Waterville location that almost quadruples the size of the store. To celebrate, it’s bringing in the husband-and-wife folk-rock duo Sarah Lee Guthrie and Johnny Irion for a free in-store concert.

It’s actually a double celebration of sorts, as the couple will perform a 30-minute set of songs from their brand-new album, “Wassaic Way,” released just this past Tuesday. Produced by Jeff Tweedy of Wilco at Wilco’s Chicago studio The Loft — with an assist by Wilco multi-instrumentalist Pat Sansone — it marks a new direction for the duo both sonically and lyrically.

“I really feel like we were able to come through on this album, unlike previous albums. The production was really done well,” Guthrie said in a phone interview. “It wasn’t the live approach that we’ve done before; this was a very deliberate and intentional process over about a six-month period I’m so nervous and excited and filled with anticipation. It’s definitely the best work we’ve ever done.”

Both Guthrie and Irion come from legendary artistic lineage — she’s the daughter of Arlo Guthrie and the granddaughter of Woody Guthrie, and he’s the grand-nephew of author John Steinbeck. They married in 1999, and have lived in western Massachusetts for about six years in a house near her parents’ place. They have two daughters, who just turned ages 6 and 11.

The Guthrie family has had ties to Wilco since the late ’90s, when the band partnered with Billy Bragg to record “Mermaid Avenue,” a collection of unrecorded Woody Guthrie lyrics set to new music. Wilco invited Sarah Lee and Johnny to perform at the Solid Sound Festival in Massachusetts in 2011, and that led to the couple asking Tweedy to produce their next record.

But Tweedy did more than just produce “Wassaic Way” — he was involved in every part of the creative process. And Sansone was equally involved in the songwriting from a musical standpoint, working with Irion on experimenting with different arrangements and chord structures.

“This was the first time we actually really opened up our lyrics,” Guthrie said. “The first day, Jeff is like, ‘Listen — nothing is precious in here. Let’s just throw out ideas, and we’ll make the best that we can do as long as no one’s holding on tightly to something that may not be best for the overall project.’ So we kind of left our baggage at the door.

“That created an atmosphere that Jeff could really be involved in the entire process. And that even came down to some of the lyrics and some of the song titles.”

Not that it was always easy to let go of the creative control.

“I lost sleep over it! Of course!” Guthrie said with a laugh. “There was a particular song called ‘Hurricane Window’ — Jeff took me aside one day just before we were about to track it, and he said, ‘Did you write this song?’ And I said, ‘No, Johnny did.’ And he said, ‘OK, good, because I don’t know what a hurricane window is.’ And I went, ‘OK, it’s a thing, it’s a real thing.’

“And he said, ‘What if we call it hurricane widow?’ And I was like, ‘Oh, that’s really cool! But no way! I’ve been loving this song for months now, you can’t change it!’ “

In the end, she compromised — the last verse was changed to “hurricane widow,” which Guthrie says “puts a twist on the end of it.”

Irion, by the way, didn’t mind changing the songs at all.

“Actually, it would be the opposite,” he said. “It would be, ‘Can I redo that?’ And he’d be like, ‘No, that’s awesome, don’t mess with it.’ “

The setlist for Saturday in still in flux — “we kind of do these things on the fly,” Guthrie said — with one exception, “Circle of Souls.”

It’s a song the couple had been kicking around for years, but which never really gelled until they got to The Loft. While they were recording the album, Guthrie’s mother died, and the song became a tribute to her. They even used her mother’s 1970s-era rhythm arranger on the track.

” ‘How I worry you might go’ — that line lent so much relevance to my life,” she said. “That line all of a sudden rang so true, because that’s the song I’m going to sing for my mom ‘Circle of Souls,’ the evergoing life cycle that we’re all a part of, whether we like it or not, there’s life and death involved.”

Guthrie and Irion are releasing “Wassaic Way” themselves on their own label, Route 8, and distributing through Redeye Music. It was through Redeye that the Bull Moose gig came about.

“They had a list of really supportive record stores, and Bull Moose was on the top of that list,” Guthrie said. “We’re of the old-school ilk of supporting your local record store, so we really wanted to pull that aspect into our little local campaign of getting the record out through independent retail. We’re all now little stores and little record companies, and we all have to stick together.”

Bull Moose’s Waterville store is located at 80 Elm Plaza. Guthrie and Irion will perform at 3 p.m. Call 861-5884 or go to bullmoosemusic.com.

Deputy Managing Editor Rod Harmon may be contacted at 791-6450 or at:

[email protected]

Twitter: RHarmonPPH