ROCKPORT — Chamber music necessitates a certain compromise between the individual and the collective . . . actually, that platitude crumbles with the Boston Trio, a chamber music group that is often at its best when its players are behaving most like soloists. When that proclivity intersects with repertoire that thrives on simultaneity — say, Charles Ives’s Piano Trio, which the group played in Rockport on Thursday — the results are breathtaking.

Ives’s college-days reminiscence replaces nostalgia with a sense of the brain’s unruly way of pulling up memories. The almost harshly Romantic opening reimagines earnest student discussions and the fraught sense of importance that drives them. Violinist Irina Muresanu and cellist Allison Eldredge made their arguments with tensile, generously bowed zeal; pianist Heng-Jin Park was an eloquent moderator, shadowing the conversation, steering the debate toward sonorous verities.

The middle movement is a brash student holiday, one of the most indefatigably energetic of Ives’s musical pileups, which the group made to seem even more gleefully chaotic by giving each bit of quoted song and snatch of ragtime full-on, insistent attention. It’s balanced by a magical finale, a long-ago morning in church, fervor on the verge of coming into focus before dissolving into a gently fading “Rock of Ages.’’ The window at the back of the Rockport Music Festival’s lovely new hall created visual counterpoint: Ives’s recollection evaporated into haze as ocean and sky slipped into a nighttime blue-gray wash.

The concert opened with Mozart’s C-major Trio, K. 548, in which the strings took their cue from Park’s fortepiano-like tone — bright but sparse, lightly pedaled, clean. The result was a little detached, crisp but comparatively impersonal. There was no such problem with the closer, Mendelssohn’s C-minor Piano Trio No. 2, Op. 66, one of that composer’s more dark and dramatic creations; even the scherzo remakes Mendelssohnian sparkle into something more like urbane demonicism. The group’s combination of extroverted emotion and finely detailed phrasing produced an enthrallingly polished anguish, a mourning dress of flamboyant elegance.

For an encore, the Trio draped their chairs with Celtics T-shirts and offered up “Spring’’ from Astor Piazzolla’s “Four Seasons of Buenos Aires.’’ Alas, within a few hours, the Celtics’ season had unhappily slipped away into summer. There’s always next year.