Last weekend, clarinetist David Shifrin made good on a long-overdue return. The director of chamber music at Lincoln Center played Mozart''s Clarinet Concerto in A with the Santa Cruz Symphony, 10 years to the day (Saturday) since his previous performance of exactly the same work with exactly the same orchestra. (In that era, Shifrin also appeared in Carmel for the Chamber Music Society--with pianist William Doppmann, et al--as a member of the subsequently disbanded Cascade Soloists, n‚e Ko-Kela Piano Quartet.)

For the Sunday performance, at Watsonville''s Mello Center, Shifrin appeared with a basset clarinet, whose extended lower range was specifically called for by the composer. Playing sans vibrato (which appeals to this listener in classical clarinet repertoire) and with impeccable pitch, Shifrin exploited the rich, round, sensuous sonorities that had plainly seduced Mozart. (During the interval, the lobby was all abuzz over Shifrin''s tone.)

This was also the first time the orchestra strings were allowed to hold sway. Earlier in the program, Joan Tower''s 1992 fanfare, For the Uncommon Woman, all but obliterated the strings with a grandiose, over-scored wind/brass band. Inspired by Copland''s Fanfare for the Common Man, the short piece is plainly PC, and though well-performed, not especially memorable.

That hope would fall to Shostakovich''s Symphony 5 in D Minor, arguably the century''s most personally anguished symphonic expression since Mahler. (Those who attended still remember the spectacular performance of the work by the SCS under Oleg Kovalenko at Santa Cruz'' Cocoanut Grove 14 years ago.)

From the outset, and from memory, John Larry Granger tackled what has to be the most ambivalent, great first movement in symphonic history. Not only does the piece pose exceptional technical challenges, but its execution calls for extraordinary interpretive instincts. How does one convey ambivalence in music unambivalently? Indeed, this proved to be the conductor''s bˆte noire. In many of its doubting moments, Granger allowed the energy to slacken and dissipate. The work''s inherent anxiety, however, demands a sustaining undercurrent of tension.

Events took a turn for the better in the subsequent three movements, the long, slow movement getting the afternoon''s highest pitch of expressive intensity, the second and fourth rolling largely on rhythmic propulsion. The orchestra likewise rose to the occasion, rattling the Mello''s rafters with rumbling contrabass tones and explosive volleys of percussion. (As noted earlier this season, the balcony gets the best symphonic sonic image.)

The Mozart Society will host Joshua Rifkin in a lecture-demonstration at Monterey Peninsula College this Sunday afternoon at 4pm. (Those who attended Rifkin''s analysis of a late Mozart chamber work some nine years ago--also sponsored by the Society--still recall the presentation with relish.) The subject of this week''s program is Mozart''s unfinished Mass in C Minor, a work whose premiere featured the composer''s wife, Constanze, in the operatic solo soprano part.

Rifkin can look back on a career of exceptional range and controversy. In the late ''60s, his contemplative playing of Scott Joplin rags began what turned into a worldwide revival. In ''81, his Bach Ensemble production of Bach''s Mass in B Minor, with a total of only five singers, ignited a storm of scholarly debate. His exquisite orchestrations for Judy Collins'' album Wildflowers are unique in the annals of contemporary American pop music. He has conducted major orchestras and taught at universities throughout the Americas, Europe, England and Australia. His musical interests and scholarships range from the early Renaissance through the late 20th century.

During a recent conversation, Rifkin described the Mozart mass as "very mysterious" and "a confused, contradictory story that is muddier than the written record asserts." Rifkin''s intellect is well-known for challenging commonly accepted accounts and homing in, with unyielding forensic scrutiny, on discovering the facts. "We know when and where it was first performed, and little else. Though it was premiered in Salzburg, Mozart had already quit that town and only returned for this production. I think it was intended for Vienna. It doesn''t fit the Salzburg patterns in technical terms, such nitty-gritty things as the number and kinds of voices and instruments."

As an unfinished work, the mass would have had limited liturgical appeal. "We know how much of it was first performed, that some of what Mozart finished was subsequently lost, and that a second performance would not have taken place until well into the 19th century." Like the unfinished Requiem, the Mass in C Minor stands as yet another pinnacle of Mozart''s art, a tantalizing torso. One could scarcely be guided through its treasures by a better docent than Joshua Rifkin.

REMINDER: Award-winning young pianist Aaron Miller''s Julliard-entrance program recital of Feb. 8 was canceled due to a fierce storm. It has been rescheduled for this Sunday, 3pm, at Santa Catalina School Performing Arts Center in Monterey.

Last Week''s Quiz: What European nation''s archive of priceless classical recordings is, for want of funding, in the greatest danger of permanent loss due to physical deterioration?

Answer: Hungary (the Hungaroton collection).

This Week''s Quiz: Who compiled the "BWV" listing of works by J.S. Bach and when was it published?

Classical Calendar

Carmina Burana

Frida

y/Saturday, 8pm; Sunday, 2&8pm. Nicole Paiement conducts UCSC Orchestra, Chamber Singers, Concert Choir in Carl Orff''s masterpiece. Music Center Recital Hall, UC Santa Cruz. $12/general; $9/seniors; $7.50/students. 459-2159.

Pianist Aaron Miller

Sunday, 3pm. Rescheduled from February 8. Performing Arts Center, Santa Catalina School, Mark Thomas Drive, Monterey. $5 donation (to benefit Music Teachers Association Scholarship Fund). 624-9541.

Pianist/Conductor Joshua Rifkin

Sunday, 4pm. Mozart Society hosts distinguished musician in a lecture-demonstration on Mozart''s Mass in C Minor. Music Hall, Monterey Peninsula College, 980 Fremont St., Monterey. Free. 625-3637.

Latin American Ensembles

Tuesday, 8pm. Taki Nan and Voces, Lydia and Hector Zapana, perform traditional music of South American countries on regional instruments. Music Center Recital