In its own individually lavish style, San Francisco staged an inaugural gala Tuesday night at the new $27-million hall of the San Francisco Symphony Orchestra, Louise M. Davies Hall.

The event was gala in a way almost forgotten in the East, with the men in white-tie and the women's dresses and jewels the subject of exhaustive analysis with illustration on the newspapers' picture pages for several days before the big party.

Further, the opening of Davies Hall is of potentially enormous importance over the long-term course of music in this arts-oriented city. The hall has been built across the street from the War Memorial Opera House, the home of the San Francisco Opera, which aside from the Met is the country's most star-studded company. For years the orchestra has had to share that house on a poor-stepsister-of-the-opera basis. Now, with two coordinated halls, San Francisco becomes the third major American city with such facilities for orchestra and opera simultaneously -- as at Lincoln Center and the Kennedy Center.

For all this to eventually work smoothy, of course, one of the most essential factors is good acoustics; and that matter is already generating heated controversy among musicians, subscribers and visiting journalists here for the event.

At the Tuesday opening no such judgment could be made with finality, given the acoustical work that has yet to be completed and the inevitable conflict between the demands of the music and the spectacle of the glitterati.

A mob of about 3,000 -- at $1,000 apiece -- was jammed into the not-yet-carpeted foyers for hours of partying. The costumes themselves were worth the effort, ranging from a conservative antique Japanese embroidered gown of the 80-year-old Mrs. Davies herself, to the seemingly casual brown tulle shoulder wrap of soprano Birgit Nilsson that was appliqued in gold leaves that were in fact made of gold, to incongruous but predictable crazies in whiteface, black top hat and white T-shirts.

The crowd was packed so tightly around dozens of tables of giant prawns, smoked salmon, champagne and other hedonistic delights, that it was very difficult to move in any direction.

During intermission, the crowding was so bad that, despite their best efforts, only about half the people could get back into the hall before conductor Edo de Waart began the concluding Beethoven's Fifth. Even Mrs. Davies hereself was caught outside.

San Francisco, with its affection for formal propriety, probably sticks to its traditional way of dress at such gatherings, well aware that it is going against the national grain, whether in Washington, or even elsewhere in Calfornia.

As one tailor told a visitor, "We're well aware that you people no longer dress formally when you go to the White House, but that doesn't affect us, and sooner or later, you'll come around." High society here, in other words, intends to stay high.

Mrs. Davies, who contributed $5 million to build the hall, is the widow of Ralph K. Davies, former chairman of the board of Natomas Co. and president of American President Lines. She has been a season-ticket holder since 1934 and seems the kind of person of wealth who, when asked about her philanthropy, goes out of her way to sound unstuffy. How did she happen to give the money? "Because I had it. That's one thing you don't give unless you have it . . . My children are well provided for -- too well provided for, in fact. I worry about that."

As for the musical part of the evening, those who stayed at home to hear the concert live on PBS may have gotten a better idea of the music than many who were there.

Musically, the most newsworthy happenings were a bravura performance of Mendelssohn's effervescent first piano concerto by Rudolf Serkin and the world premiere of a commissioned work by important young composer David Del Tredici.

Called "Happy Voices," it is another in the long series of compositions he has based on the writings of Lewis Carroll, one of which won last year's Pulitzer Prize. This 20-minute composition for orchestra (with a brief vocal passage at the end), contains more fun than substance.

Harmonically, it recalled the early Bernstein without the beat. (Imagine Bernstein without a beat!) Instead there was an Ivesian undercurrent that gave the illusion, at least, of forward progression.

But in the louder passages, the downright unpleasant racket produced by the five hard-pressed percussionists obscured most else. Constant crash cymbals and the "high anvil effect" irritated the ears -- in these acoustics, at least.

Davies Hall is one of those auditoriums that is "tuned" with elaborate engineering devices, rather than simply "designed" once and for all, as in the Kennedy Center halls. Right now, the Davies Hall acousticians admit that the hall is not yet "tuned" and the price now being paid for that is amply apparent.

Low frequencies seemed to get eaten up in most parts of the handsome room, which is of the wrap-around design, with some listeners sitting behind and to the sides of the orchestra. Players at the back of the stage complained that they could not hear the strings, the audience often complained they could not hear the winds, and ensembles were frequently ragged despite De Waart's fervent work to prevent it.

Musicians tend to mistrust such halls, especially in light of the problems of New York's original Philharmonic Hall, also designed by the same firm, Bolt, Beranek and Newman, and eventually redesigned totally. But Theodore Schulz, who is in charge of the San Francisco project, gives assurance that, with time, the problems of Davies Hall will be solved.

The building itself is a bland and inoffensive product resembling a halfdome, designed by Skidmore, Owings and Merrill, with Pietro Belluschi.

So, if Davies Hall itself is not yet the new pride of San Francisco, the capacity it provides to operate in a new cultural league is.

Last night black-tie audiences flocked to the opera for Verdi's "Simone Boccanegra," while the symphony hall acoustics endured a new test, Mahler's gargantuan Eighth Symphony. CAPTION: Picture, The San Francisco Symphony playing in its new $27 million hall.