For a guy whose new record features as much piano playing as guitar work, Alan Sparhawk sure doesn’t make a very good salesman for either the ivories or his album.

“Using the piano can be fraught with clichés,” said the frontman of Duluth’s beloved somber-rock trio Low. “A lot of times, it’s just used like a sprinkling of fairy dust to make a song sound prettier. That’s not what we were going for.”

Indeed, the piano takes on darker and wearier tones on “The Invisible Way,” Low’s impressive 10th album, which lands Tuesday on famed Seattle indie label Sub Pop Records. Interest in the record is a little higher this time around, thanks to who produced it: Jeff Tweedy, leader of Chicago rock band Wilco.

Tweedy is the latest in a string of more famous rockers to lend exposure to Low, which Sparhawk has been leading for 20 years with his wife, Mimi Parker. Robert Plant of Led Zeppelin recorded two of the band’s songs for his 2010 album “Band of Joy,” and Radiohead and Death Cab for Cutie have recruited Low to open their tours.

The Duluthians have also done a few outings with Wilco, whose guitarist Nels Cline is a longtime cohort of theirs. Sparhawk hesitated to say he and Tweedy were tight pals — “We jogged together a few times; that’s pretty close, I suppose” — but it was Tweedy who offered up his studio/rehearsal space in Chicago. He won a Grammy for producing soul legend Mavis Staples’ most recent album there.

When Low hit the studio, Sparhawk recounted, “Jeff told us upfront, ‘You guys know how to do what you do. I’m not going to be concerned with that.’ So he focused his energy more on making sure everything sounded right and there was the right energy in the room — which he was good at, since it’s his room.”

Even before they started recording, it was apparent this would be a different album for Low. Many of the songs were written on piano instead of guitar — which is because many of them were written by Parker. She sings lead in five of the 11 songs on “The Invisible Way,” much more than on any previous record. They include such key tracks as the steamrolling Velvet Underground-ish gem “Just Make It Stop,” the downfall-tinged finale “On Our Knees,” plus “Four Score,” a numb-sounding critique of the financial crisis.

Since Low’s inception, Sparhawk has always been in the spotlight while his wife hung in the back behind a stand-up drum kit, offering vital but subtle support with her serene, siren-like voice. Their on-stage roles reflected their off-stage personalities, with him being more gregarious and wily, and her more aloof and even-keeled. Somewhere in between is Steve Garrington, the band’s bassist for five years running and a bandmate in Sparhawk’s noisier trio, Retribution Gospel Choir.

With a little encouragement and more time, Parker rose to Sparhawk’s challenge to play a more central role on “The Invisible Way.”

“The running joke has been that one of these days we’ll make a record that’s entirely Mim singing,” Sparhawk said, using his nickname for her, “and it will probably wind up being our most successful record. But I don’t think she’d have that. She’s perfectly content with her usual role, so this will probably be about as front-and-center as she’ll get.”

Sparhawk’s own songs include one named for a musician who has nothing to do with the lyrics: “Clarence White,” a slow, hand-clap-infused howler (White was a guitarist with the Byrds and others). Another is actually about a musician but doesn’t name him: The mostly acoustic opening track “Plastic Cup” is loosely based on the experiences of Retribution Gospel Choir drummer and sometimes Low keyboardist Eric Pollard, who was convicted of selling marijuana but bounced back to become burgeoning songwriter/bandleader Actual Wolf.

“Maybe you should go out and write your own damn song,” Sparhawk sings, following pointed lyrics about drug tests and, he said, “society’s modern way of deciding that one thing is right and one is wrong.” While not exactly rare territory for rock musicians, it does seem uncommon for a practicing Mormon like Sparhawk. (“I’m proud of Eric,” he clarified.)

For their Twin Cities album-release concert, Low will bring fellow Duluth music heroes Trampled by Turtles as collaborators for a special “Current Sessions” taping Saturday at the Fitzgerald Theater. “The more we rehearse, the more it looks like they’re going to play almost the whole show with us,” Sparhawk happily reported.

Saturday’s concert is doubling as a 20th-anniversary celebration for the band, which formed after the childhood sweethearts from the puny wild-rice-cultivating town of Clearbrook, Minn., settled in Duluth. Proof that their band is going strong lies in the rest of their 2013 itinerary, which includes a three-week theater tour in Europe, a slot at Wilco’s Solid Sound festival and select U.S. gigs at such venerable venues as San Francisco’s Great American Music Hall and the Troubadour in Los Angeles. (With two grade-school children at home, they no longer do extended U.S. hauls.)

Asked for words of wisdom to mark the anniversary, Sparhawk scoffed: “I think the secret to our longevity has been not knowing or really ever even thinking we’d be doing it this long. It really did help not knowing what we were doing.”