The atmosphere at TD Garden ahead of Bon Iver’s Oct. 15 performance felt isolating. Smoke from Feist’s opening set and the illicit activity of individual audience members clouded the air like the aftermath of a fire. The venue divided the floor into eight seated sections, eliminating the communal nature of a pit. Two video screens displayed video footage of a solitary man shooting free throws on a desolate basketball court as a graphic tracked his performance. Each successful shot was accompanied by cheers in other cities, but Boston remained silent. These conditions fostered a growing sense of dread, suggesting that Bon Iver didn’t belong in the cavernous arena fit for nearly 20,000 people.

Bon Iver’s music evokes feelings of isolation and introspection. The story behind the project’s first album, 2007’s “For Emma, Forever Ago,” is indie legend. Justin Vernon, kicked out of his band, dumped by his girlfriend, and suffering from mono, escaped to northwest Wisconsin to record a painfully beautiful set of songs centered on loss, despair, and acceptance. The album cover’s frosted windowpane served as a hallmark of winter, making “For Emma” the kind of album best enjoyed with a hot beverage in a cozy armchair by the fireplace while snow falls outside. Spring came with Bon Iver’s second, self-titled record in 2011. Bon Iver matured sonically with more elaborate instrumentation, and naming each song after a place implied a reentry into society after isolation in the cabin. 2016’s “22, A Million” featured opaque song titles and embraced an electronic, modernist approach, culminating in a sound the band described as that of an “unhinged summer.” The trio of albums seemed to point to an even more elusive and experimental sound from their next release.

Instead, September’s “i,i” blended the orchestral folkiness of their self-titled album with the progressive structures of “22, A Million.” The album begins with songs like “iMi” and “We” that lean on samples and vocal modifications and transitions to a more traditional-sounding back half. Even there, the collectivist message of “Salem” and saxophone solo of “Sh’Diah” demonstrate the project’s evolution over time. Similar to The National’s “I Am Easy to Find,” Bon Iver have stayed fresh by expanding its scope and adding new voices. The biggest question for the band, however, was whether that message would translate in a hockey arena.

To prep for its biggest tour yet, Bon Iver invested heavily in its tech. The band used a sound system called L-ISA that created a stereo sound throughout the arena, allowing the audience to distinctly hear where each sound on the stage came from — in effect, giving the balcony the acoustics of floor seats. They also installed moving, overhead mirrors that dynamically reflected light around the arena. The mirrors adapted to each song, creating ornate displays throughout the set. These advancements created a unique concert experience and gave Bon Iver the ability to command such a large venue.

And command they did. The group’s set demonstrated that they were more than just smoke and mirrors. Vernon, admitting Bon Iver are “not the usual suspects in a big ol’ place like this,” nevertheless brought commanding vocals and a gripping falsetto to the stage. Band members Sean Carey (keyboard) and Matthew McCaughan (drums) impressed during full-band renditions of new songs “Holyfields,” and “We.” The band members brought tremendous energy during songs like main set closer “Naeem,” yelling with Vernon during its anthemic chorus.

Bon Iver also shined during reimagined versions of older songs. “Blood Bank,” a song Vernon chose not to release on “For Emma,” underwent a hard-rock makeover, complete with a guitar solo and extended jam. On “Perth,” McCaughan’s drums were somehow even more dominant than on the studio version. The band demonstrated the elasticity of “For Emma” by performing an eerie rendition of “Lump Sum,” proving that even Vernon’s most intimate songs can play to the largest of audiences.

All this being said, the highlights of the night were Vernon’s solo efforts. “715 - CR∑∑KS,” a vocal powerhouse off “22, A Million,” took on new life as Vernon manipulated his Messina, an autotuner that preserves the original voice but adds in real-time harmonies. Vernon also gave an emotional performance of his most popular song, “Skinny Love,” with just his voice and acoustic guitar. The raw passion behind the “For Emma” cut floated throughout the arena. On the other hand, the meandering “____45_____” made for an interesting, but unfit encore — the closest thing to a misstep all night.

Bon Iver’s performance at TD Garden was a testament to their immense growth. The project that started in a hunting cabin morphed into a collaborative band that emphasized togetherness. Nowhere was this more evident than the closer, “RABi,” which Vernon kicked off by proclaiming that “Life is long. Be good to each other and don’t be afraid of what comes after.” In response to the band repeatedly teasing “So what of this release?” between verses, Vernon finished by singing that “Well, it’s all fine and we’re all fine anyway.” An elaborate light display illuminated most of the audience standing in unison, the crowd’s transition from isolation to solidarity mirroring Bon Iver’s.

— Staff Writer Jack M. Schroeder can be reached at jack.schroeder@thecrimson.com.