Challenges don’t distract string quartet

Against considerable odds, the Johannes String Quartet, one of the more promising young American ensembles, made its West Coast debut Sunday afternoon. The odds included a substitute second violinist, a changed program and all the related stress.

Still, the performance of the ensemble was a triumph.

Soovin Kim, who regularly alternates first-violinist duties with Robert Chen in this ensemble, took over at that position while Chen remained at home in Chicago for the impending birth of his child. Regular members C.J. Chang (associate principal viola of the Chicago Symphony) and Peter Stumpf (principal cello of the Los Angeles Philharmonic) maintained their duties in a masterly fashion.

The quartet has a long association with the Marlboro Music Festival in Vermont, and it was to a Marlboro connection -- Catherine Cho, a member of the Juilliard School faculty -- that they turned for a second violinist. She delivered seamlessly.

The reformulated program, encompassing Mozart’s “Dissonant” Quartet, K. 465, and the Debussy Quartet, displayed the four players’ marvelous tonal palettes, resourceful dynamics, imperturbable balances and musical single-mindedness.

Aggressiveness without stridency and linear continuity are the ensemble’s chief virtues. Those and the foursome’s personal charisma make their performances important.

Their Mozart sang forth effortlessly, but it also exploded as needed and touched emotional bases. The virile second movement of the Debussy work was followed by a lyrical, magic reading of the Andantino. The Chamber Music in Historic Sites audience gathered in the Canfield-Moreno House in Silver Lake was appropriately touched.