It is hard to listen to the music that the members of the Emerson String Quartet make and not be conscious of how they make it. Theirs is a level of cooperation and adjustment, teamwork and selflessness that is a byproduct of devotion to the music, but is, in itself, a fascinating dimension of their art.

Their intense collaboration was the perfect vehicle for the program of works by Debussy and Ravel at the Renwick on Saturday and again yesterday. Each composer wrote a quartet in which textures, light and changing moods are a challenge to the concentration of the finest ensemble. There is nothing spontaneous about this music. Every shade of color must be contrived, every pizzicato balanced against the other textures in the ensemble. But in the end, what must be communicated is subtlety, not artificiality, and it was here that the Emerson was so successful.

The slow movements of the quartets and of the Sonata for Violin and Cello by Ravel provided the clearest examples of this concentration at work. Because the music unfolds slowly, it was possibly to see the intensity of this concentration, and the audience, under its spell, was held entirely still.

But it was this same intensity of focus that gave the fast movements their rhythmic integrity and produced that characteristic French string tone that so accurately reflects the quality and inflection of French speech.

After having heard this performance, it is hard to conceive of this music being played any other way. --