* March 6-8 -- The rarely performed "Requiem" by Hector Berlioz, one of the 19th century's most dramatic composers, will be presented by about 500 singers and instrumentalists, including four brass choirs and 16 timpani players. Written especially to be heard in large cathedrals, the piece will be performed at 8 p.m. Friday, March 6, in the Cathedral of the Blessed Sacrament, 11th & K Streets, Sacramento; at 8:30 p.m. Saturday, March 7, in St. Mary's Cathedral, 1111 Gough Street, San Francisco; and at 8 p.m. Sunday, March 8, in Freeborn Hall on the Davis campus.