KALAMAZOO, MI — Saturday’s Fontana Chamber Artsconcert was bittersweet. On stage, before a full house at Dalton Center Recital Hall, was the legendary Tokyo String Quartet, poised for another sublime performance in its storied career. But the large audience realized it would be for the last time: after this, its farewell concert tour, the Tokyo quartet is disbanding.

Since its founding in 1969, the quartet earned its way to the world’s uppermost echelon of string ensembles. The players—violinists Martin Beaver and Kikuei Ikeda, violist Kazuhide Isomura and cellist Clive Greensmith—have individual plans now to continue in music, but not as a single entity.

A cognizance of their pending absence from the musical scene became clear with Saturday’s performance. The program, comprised of challenging but rewarding works by Beethoven, Webern and Schubert, required artistry reflecting acute imagination.

Beethoven’s sharply focused Quartet in F minor, Op. 95, “Serioso” (1810) opened with a powerful burst of energy. A whirlwind of notes established a sense of agitation, reinforced by swiftly shifting dynamics. Yet the players remained supremely unified, setting an appropriate tempo (one not overly fast) that allowed mellowness in overall sound.

The Tokyo players achieved what Beethoven sought. Each instrumentalist displayed masterful command of pure, narrow tones. Without thick sounds to overflow and blur, complicated phrasing stayed focused and clear. Isomura excelled in the first movement, with Greensmith’s rocking pattern and Beaver’s ethereal high notes notable in later sections. A presto finale blistered in its quickness.

After intermission, Schubert’s Quartet in G Major, Op. 161, D. 887 (1826) held forth. Called the Everest of quartet music by Beaver in remarks to the audience, this lengthy Schubert masterwork relied on vast stretches of tremolo playing, creating a shimmery aura. Stunningly beautiful—not surprising for this composer—the piece, as the Tokyo quartet approached it, exhibited exciting dynamics along with fetching melodic lines that overflowed with vitality.

Greensmith stood out in the second movement where he provided yeoman service. In the third, all four players contributed to a rollicking, almost boisterous frolic. Dynamics were spot on, with tremolo again a dominant feature. The final movement began with rhythmic ambiguity but settled in for a jolly conclusion.

Prior to the intermission, the ensemble gorgeously performed Webern’s early String Quartet, 1905—composed before he turned to 12-tone atonality. The lyrical phrases and unsettled yet lush harmonies captured Romanticism perfectly. We shall sorely miss this consummate ensemble.