At UCLA’s Schoenberg Hall, the Eighth Quartet served to conclude a dazzling evening by the St. Lawrence String Quartet, the new ensemble out of Canada that has become the darling of the chamber-music world. Everybody loves them for the sheen of their performance style, and the way they have of playing straight out to the crowd: something like the Lang Lang approach, except that they play better music. At Schoenberg they gave an edge-of-the-seat performance of the Shostakovich; before that they played the Ravel Quartet with such elegance, such purity, that it seemed to hang suspended. Before that they played Osvaldo Golijov. Their best-selling disc (on EMI/Angel) has the Golijov pan-national repertory: the phenomenal Yiddishbbuk inspired by inscriptions from Prague ghetto walls, the klezmer-inspired Dreams and Prayersof Isaac the Blind (with clarinet), and his Last Round, which the Philharmonic has done here orchestrally. At Schoenberg the St. Lawrence played just the Yiddishbbuk, haunting and exhilarating. Get the disc, and be prepared to dance on the ceiling.