Väsen brings Swedish folk traditions into fresh new territory.

Väsen speaks in a musical language learned over 29 years of performing together, which still has nothing on the nyckelharpa, a 16-stringed traditional Swedish instrument some 600 years old. Olov Johansson (nyckelharpa) and Mikael Marin (viola) have played music together since they were teenagers in the early ’80s. They met 12-string guitarist Roger Tallroth in 1989 at a fateful music gathering in Norway. Initially, Johansson asked Tallroth if he’d like to jam, and he turned down the offer to instead take a shower. Serendipitously, the shower was already in use, so Tallroth returned to jam for the rest of the night. The trio has yet to stop jamming.

Their trick to long-lasting success comes from a genuine joy of playing together, “without too much analyzing or talking throughout the process,” says Tallroth, who answered questions from Uppsala, Sweden. With a collective soul founded on “respect, trust and musical freedom,” the band plays perfectly in sync, seemingly predicting each other’s next notes, even when improvising.

The Swedish word “väsen” means essence, spirit or a living being. The trio’s music is delightfully rooted in the essence of Nordic folk – paying homage to an acoustic old world tradition. It’s the kind of music that can give listeners goose bumps through the skin right down to the bone, as if ancient ancestral spirits internally rejoice in nostalgia.

The trio pulls from their region’s traditional folk roots through their techniques. Compared to American folk, Swedish folk generally elongates musical progressions and melodies, with more improvisation but fewer “solos,” similar to American bluegrass.

For their first visit to Henry Miller Memorial Library, the band looks forward to performing a unique show, which will be recorded inside the library’s self-described “acoustically amazing” bookroom.

Tallroth has a hard time pinpointing a highlight in a long career: “Every moment that reminds me of why I started to play music and why I kept doing it over all these years is great,” he says. “And Väsen is the band that keep reminding me of just that.”

VÄSEN 7-9pm Monday, Feb. 26. Henry Miller Library, 48603 Highway 1, Big Sur. $30. 667-2574, henrymiller.org