SUNDAY CONCERTS WAKE UP L.A.

Once in a while, against expectations and against this city’s long tradition of decentralized growth, you are granted a teasing look at the heart of Los Angeles as more than a five-day, 9-to-5 place of trade and administration, from which everybody goes home after dark and seldom sees on weekends.

Downtown Los Angeles looks more like the center of a great city in the world tradition than it ever has, and its shiny new towers extrude a weekday noontime street life that is colorful and exciting.

Like the Music Center complex before them, the Temporary Contemporary and shortly the Permanent Contemporary art museums and the Dance Center are new destinations to lure the crowds back to mid-town in off-hours, and the Los Angeles Theater Center struggles bravely to become a beacon, pushing back the encircling gloom of Spring Street by night.

Yet the question remains whether the bustling street life that gives Broadway, Little Tokyo and Chinatown their vitality and interest is destined to remain only an ethnic phenomenon. Elsewhere in the central city what teems with downtown life at noon presents only a handsome but impenetrable sterility after closing time. Some dream of intimacy and informality has fallen off the drawing boards.

It is not a Los Angeles phenomenon exclusively, and other cities from Boston west have had to set up other drawing boards to restore the warmth and the human dimension that did not get into the high-rising plans. There are signs of change, but they are slow.

The tastes of what might yet be are the more tantalizing because they don’t seem impossible dreams, beyond reasonable reach, even in a metropolis that has learned to find its intimacy and its human dimensions in suburban shopping malls.

The other Sunday morning there were stands offering coffee and very good croissants on the promenade between the Mark Taper Forum and the Pavilion at the Music Center. Breakfast came with the price of the tickets to a chamber music concert in the Taper that began at 11, in front of the set of “The Migrant.”

Chamber music has to be the most rarefied of the performing arts, not easy to warm to until you’ve heard it done live and well. Radio and even hi-fi stress the thin, austere gravity it can undoubtedly have. Live performance reveals the gaiety, the extraordinary skill asked of the artists and the unearthly beauty of the music at its most feeling.

Once heard live and well, it can become an addiction that cuts across any other demographics you can think of, as it seemed to have the other Sunday morning. It was a disparate crowd, young and old, some in shirt sleeves, all drawn to interrupt their day by an enthusiasm edging on passion.

This is the seventh season of the Sunday morning series, which was conceived by Eugene Golden, a Beverly Hills lawyer and investor who found major additional backing for the recitals from the Safeco Title Insurance Co. (Despite good attendance and considerable volunteerism, the concerts lose money.)

Henri Temianka is artistic director of the concerts, most of whose players are associated with his California Chamber Symphony Society. The first of this season’s three concerts was all Brahms, his Trio in B, Opus 8 and his Quartet in G minor, Opus 25, with Antoinette Perry, piano; Joseph Genualdi, violin; Peter Rejto, cello; and Sophie Renshaw, viola.

At a guess, none is yet acquainted with the age of 40, and in their youthful verve and their assured and eloquent playing they conveyed a sense of renewal and continuity that was not the least of the morning’s charms.

Temianka, who toured for years with the Paganini String Quartet, has been spreading the gospel of chamber music in Los Angeles for 36 years, at youth concerts, a Sunday series at the Getty Museum, a long-running series at Royce Hall at UCLA now at Pepperdine, more recently a series at a retirement village in Ocean Hills. He and his Chamber Symphony also tour nationally.

Temianka will be 80 on Nov. 19, but he is celebrating early. There is a sold-out concert in his honor, a fund-raiser for the Chamber Symphony, tonight at the Beverly-Wilshire, with his old friend Isaac Stern among the artists, along with cellist Janos Starker, guitarist Angel Romero and pianist Dudley Moore.

The Sunday morning concerts, bearing the handy descriptive title “Coffee & Croissants and Chamber Music at the Taper,” please Temianka because they re-create the ambiance of sound and socializing that surrounded chamber music in its early courtly and aristocratic days.

“In Beethoven’s time,” Temianka says, “there were chamber concerts at 8 in the morning. It would be interesting to know why that hour . . . and how many showed up.”

Whether Gene Golden can find backing for future seasons of the croissant concerts is not certain. But he has proved there are audiences for a different beat in the heart of downtown.

The two remaining Sunday morning concerts are Oct. 26 and Nov. 9. Information: (213) 478-0581.