“It’s like ASMR,” one girl in the audience whispered, dazed and vaguely incredulous, halfway through Yo La Tengo’s first set at the Jefferson Theater on Sunday night. In any other world, likening a famed indie rock band to a sensation that’s perhaps best known for the ability to induce sleep wouldn’t be a good thing. But Yo La Tengo is a band that’s always seemed to exist in a different, kinder and slightly more magical world. Subscribe to our Arts & Entertainment newsletter Dressed casually in a striped T-shirt and jeans, vocalist and guitarist Ira Kaplan cut a largely unassuming figure onstage — he projects the pleasant, avuncular air of a friend’s kindly dad or one’s favorite substitute teacher. Additionally, Kaplan is fairly taciturn when not singing. He only stopped to address the crowd a handful of times — at one point politely thanking them for coming out on a school night and later wryly wishing one audience member a happy birthday. Transitions between songs, too, were seamless and notably devoid of any small talk or banter between him and the other band members, percussionist and vocalist Georgia Hubley — to whom Kaplan is also married — and bassist James McNew, yet never awkward. Perhaps owing to their nearly 26 years together, the band’s rapport was evident onstage and even seemed to enfold the crowd within its easy warmth. The show itself was split into two sets. The first was a relatively relaxed journey through Yo La Tengo’s repertoire, opening with “You Are Here,” a warm, ambient instrumental track that leads their latest album, “There’s a Riot Going On.” Other numbers included a hushed acoustic rendition of “Deeper Into Movies” and the spare, percussion-guided “Here You Are,” the latter track providing a bookend to the quietly wondrous first act. In contrast, the band’s second set was a veritable explosion of sound. The ethereal “Dream Dream Away” immediately slid into the familiar, fuzzed-out tab of “Cherry Chapstick,” a perpetual crowd-pleaser that combines wistful lyrics and biting guitar riffs into a song that feels both razor-sharp and thoroughly lovely. At times, the yowling drone radiating off the stage was overwhelming — but more than anything, every sound felt blisteringly alive. Kaplan’s subdued appearance also belied his status as one of indie rock’s most engaging and versatile performers. He seemed equally in his element while performing the cheerful, mannerly keyboard-driven tracks “Shades of Blue” and “Mr. Tough,” as he did while hefting his guitar like a machete and delivering utterly devastating shreds on “I Heard You Looking,” a bombastic closing number that also featured Joe Puleo on the organ. When the band returned to the stage for a triumphant encore, it felt almost like an exhale. After energetic covers of DEVO’s “Gates of Steel” and Richard Hell’s “The Kid With the Replaceable Head,” Kaplan and Hubley disarmed themselves of their electric guitar and drums respectively to perform an intimate, stripped-down version of their hit “You Can Have It All,” itself a cover of a disco-tinged original by George McCrae. The song is almost goofily open-hearted and yet unbelievably beautiful, punctuated by softly-sung dual implorations to “take it, baby” that glide over a constant murmur of Kaplan’s “ba-ba-ba-ba-ba-bas.” Listening to it live — even in a room of hundreds of other people — is its own kind of enchantment. It was almost an hour to midnight by the time the crowd finally spilled outside onto the streets of the Downtown Mall, and yet somehow, the world seemed a little brighter.