A glance at the Coleman Chamber Music Assn.'s 97th season indicates that the series isn't quite as tradition-bound as its reputation would have it; every program but one contains a healthy representation of music from the 20th century. The one exception was the season-opener, where the Guarneri String Quartet offered the reliable strains of Mozart, Brahms and Mendelssohn to a nearly packed Beckman Auditorium at Caltech on Sunday afternoon.
Yet even here, there was a wisp of enterprise, for the Mendelssohn Quartet No. 1, Opus 12, apparently had not been heard at a Coleman concert before. Hard to say why, for this is another accomplished miracle of the composer's youth (he was 20 when he wrote it), highlighted by one of his best light-footed scherzos in the canzonetta and a subdued, thoughtful coda.
Upon hearing the Guarneri Quartet in 2000, inevitably one turns back a decade or two to some nearly superhuman live performances, where the ensemble played like a sleek, unanimous, incredibly fine-tuned single instrument. Yet on this afternoon, the fabric seemed a bit frayed in several passages--the scrappy doppio movimento variation in the finale of the Brahms Opus 67 Quartet and the first movement of the Mozart K. 575 Quartet come to mind. They're human now, and you can hear some struggle--which may be actually reassuring and even engaging.