``We're not afraid to write pretty music,'' Aptos' gray eminence Lou Harrison likes to say of California composers.

Add Giya Kancheli to the list of honorary Californians.

The Russian has turned out hundreds of appealing measures for symphony, film and theater. His latest, ``Don't Grieve'' for baritone and orchestra, was introduced Wednesday night by Michael Tilson Thomas and the San Francisco Symphony. Tilson Thomas commissioned the new score, which was sung by Dmitri Hvorostovsky.

Though its text and title are weak links, ``Don't Grieve'' is a melodious, melancholic and nearly persuasive score. The performers gave it a sheen and conviction that warrants further listening.

Kancheli was in Davies Hall on Wednesday to enjoy his exuberant ovation. His was the centerpiece of an atmospherically challenging program, which included the prelude to Mussorgsky's opera ``Khovanshchina'' (Rimsky-Korsakov's arrangement) delicately rendered, and Ravel's complete choral-orchestral score for the ballet ``Daphnis et Chloé.'' The Ravel, performed as usual without dancers, was a showpiece for the exemplary San Francisco Symphony Chorus, which rarely gets to sing the whole thing.

Born in Tbilisi, Georgia, in 1935, Kancheli now lives in Antwerp, Belgium. He's in that cohort dubbed the ``new mystics.'' Members include the brilliant minimalist Arvo Part and the compellingly complex Sofia Gubaidulina. Their music is more substantial, holding its own without being programmatic. Kancheli's creativity seems better suited to film scoring -- an observation not intended as insult.

What he offers is more akin to the swashbuckling emotion of Pole Henryk Górecki, whose third symphony-with-soprano topped the Billboard charts when Dawn Upshaw recorded it. ``Don't Grieve,'' should it be recorded, could be Kancheli's Billboard topper.

Think ``Carmina Burana'' without the chorus to get a rhythmic sense of ``Don't Grieve,'' whose text is a compilation of poetic lines (Shakespeare, Mandelstam, Brodsky and the composer himself). Kancheli has turned them into a collage whose musical stanzas alternate slow to fast and quiet to cataclysmic. Think of Gustav Mahler meeting Barbra Streisand to get a sense of the best melodies.

Bafflingly, the vocal impressions faded faster than Chinese takeout while some instrumental affects remained. The ensemble includes accordion, electric bass and cymbals hit by fist.

The composer completed his symphony six days before Sept. 11, and after the tragedy decided upon the title, which are the last two words sung. ``Don't grieve'' also is the name of a 1969 film that Kancheli scored, though the music is not related.

It has been a year since Alexander Barantschik took over the orchestra as concertmaster, and there's a resulting sheen and precision to the string sections. The orchestra is playing better than ever; the virtuosity of principal flute Paul Renzi in the Ravel was as impressive as the choruses' wordless ardor.