At 75, the tireless and innovative Meredith Monk continues to compose, to sing and to perform her wonderfully unclassifiable stage works. This weekend, she’s on hand as a special guest artist with the San Francisco Contemporary Music Players, in a program that includes an onstage conversation with Artistic Director Eric Dudley and short excerpts from two of her early works. The program bustles with other delights as well, including music by Frederic Rzewski, John Zorn and Don Byron. — Joshua Kosman San Francisco Contemporary Music Players: 7:30 p.m.