CLASSICAL MUSIC : On the Verge : Kent Nagano has been called the next Leonard Bernstein and the most important American conductor of his generation. So, when will the Big Leap happen? In time.

Everything about the performance seemed natural, confident, vibrant, at the British premiere of John Adams’ Violin Concerto recently given by the London Symphony Orchestra.

Of course, there were backstage tensions. The composer, himself a conductor, later confessed that the desire to conduct his own music has become so strong that he had to hold his arm down like Dr. Strangelove.

The soloist, the Russian violinist Gidon Kremer, likes to play everything differently each time he plays it, especially when he gets a new concerto so mysterious and rich in expression that he is just getting to the bottom of it.

And a British Rail strike had robbed a very overworked British orchestra of some of the already brief rehearsal time it had for a score full of very American rhythmic difficulties.

But whatever pressures and insecurities these might have caused, what occurred on the stage seemed natural, confident, vibrant, because Kent Nagano was conducting.

Most really persuasive conductors are noisy people, full of bluster and panache; they pretty much have to be in order to command an army of musicians and captivate an audience at the same time. Conversely, most quiet conductors--unless they happen to be unusually illuminating, like Pierre Boulez, or unusually elegant, the way Pierre Monteux was--tend to be satisfied with workmanlike performances. That is to say, the quiet Germans, British, Italians, Americans, Russians are likely to be dull. Only a few quiet French seem to be able to get away with brilliance.

And, now, there is a quiet American, one who displays some of Boulez’s clarity and insight and Monteux’s suavity along with a certain understated but vivid theatricality all his own.

It may not appear so from a perusal of Nagano’s very British program with the quintessentially British Halle Orchestra this week at the Hollywood Bowl in conjunction with the UK/LA Festival, but Nagano happens to be almost quintessentially melting-pot American.

He is a third-generation Japanese American who grew up on a farm in Morro Bay, who tooled around in sports cars and listened to rock ‘n’ roll in the ‘60s, and who surfs.

It may also come as news to many who do not follow the international music scene closely that the 41-year-old Nagano is now generally felt to be the most important American conductor of his generation. In his careful, determined way, Nagano, who heads the Berkeley Symphony Orchestra, the Lyon Opera in France and the Halle Orchestra in Manchester, England, has been building a very important career in secondary cities.

It will probably come as news to most Angelenos, who might remember Nagano from a couple of seasons at Ojai in the ‘80s, from a low-key debut conducting the Los Angeles Philharmonic at the Hollywood Bowl eight years ago and from two appearances at Music Center Opera (Adams’ “Nixon in China” and Kurt Weill’s “The Rise and Fall of the City of Mahagonny”).

It certainly came as news to New Yorkers last season. Five years ago Nagano led somewhat lackluster concerts with the New York Philharmonic and the Brooklyn Philharmonic. (He had also conducted the New York premiere of Adams’ opera “The Death of Klinghoffer,” but the subject of the opera so infuriated the ethnic populations that Nagano’s contribution was lost in the storm of controversy--although his cool at the stormy atmosphere surrounding the opera’s premiere in Brussels was lost on no one.)

This past season, however, Nagano returned to New York to conduct a program with the American Composers Orchestra that included Adams’ “El Dorado” and an obscure Hindemith symphony, and a revival of Metropolitan Opera’s production of Poulenc’s “The Dialogues of the Carmelites.”

While hardly disrespectable, these were not the most prestigious of New York dates nor did they represent the most popular of repertoire. But this time the raves were unanimous. At the Met, Nagano got thunderous ovations, the equal of those for two sopranos in the cast who have cult followings--Teresa Stratas and Dawn Upshaw. Then New York magazine upped the ante, producing the city’s highest praise. In a headline for a profile of the conductor, it screamed, “The New Lenny.”

But Nagano is nothing like Leonard Bernstein. Bernstein was a loud personality, Nagano is not. By Nagano’s age, Bernstein was music director of the New York Philharmonic, a huge television personality, a best-selling recording artist and the composer of hit Broadway musicals and substantial works.

Nagano is none of those things, and not even close. Bernstein, who had grabbed celebrity from the start, was the first American conductor to make a big career without going to Europe. Nagano, on the other hand, has built a career slowly and done it primarily in Europe.

Bernstein was a podium extrovert. Nagano, while a striking podium presence with his long hair and leonine gestures, moves more in service of musical execution than to achieve personal expression.

But in a subtle and important sense, Nagano may well be the next Lenny by simply not trying to be like Bernstein at all. Bernstein’s great accomplishment was to be himself, an American Jew, when that wasn’t supposed to be a viable mold for a conductor to fit into. And likewise, Nagano, never forgetting his roots, has calmly and thoughtfully helped turn the sleepy Lyon Opera into one of the most alluring and most talked-about companies in Europe.

In London, where he conducts regularly as the principal guest conductor of the London Symphony, Nagano gets much better reviews then do the music directors of most of the other London orchestras. With Halle, where he was hired to revitalize what had once been an important orchestra in what had once been an important city, he seems, after only two full seasons, to have already done so. In Berkeley, where he has remained faithful to the orchestra that helped give him his start, he has created a small miracle.

Ironically, being a Californian may well have served as Nagano’s key to successful adaptation to such very different traditions as those in Lyon and Manchester (the Halle is the oldest orchestra in Britain) while still keeping his roots in countercultural Berkeley.

“I really like California, where I grew up,” Nagano explains at a recording session for the Adams concerto, where his elegant manner makes him seem equally at ease with the California composer, British musicians and Russian violinist.

“But I think maybe part of our culture, or part of being a Californian, is that it nurtures a natural sense of curiosity and a sense of flexibility. And that lends itself not just to going someplace and imposing yourself on that place as a foreigner playing the role of a tourist. It’s true, I admit, I’ll never pass as a Frenchman; I’ll never pass as British citizen either. But that’s not to say that you can’t be a part of these communities.

“The communities today, as they probably always have been, are a very complex combination of very diverse backgrounds. That’s why we’ve always had bursts of social creativity along with bursts of social tension. They both come from those differences. And it’s those differences that, for me, make a community particularly interesting.

“So I am pretty convinced that if you’re willing to put quite a bit of effort to learn languages, to learn customs, to suppress your own criticism and try to learn something instead, you can go a long way toward belonging to part of a community and at least beginning to understand it.

“The purpose of music is really to share. If music represents those parts of life worth living--and that’s a quote that’s not mine, unfortunately, but it’s a wonderful quote--then that’s certainly worth sharing with as many people as possible. But to just share doesn’t mean giving something without sensitivity to how the other person feels. That sharing implies that you’re making an effort toward those people with whom you’re trying to share.”

Building ties with the communities may help explain why Nagano has had the successes he has had and why he may not have always made a big first impression when he had initial opportunities to conduct orchestras such as the New York Philharmonic or the Los Angeles Philharmonic and had to prove himself in a week.

Nagano’s first community was Morro Bay. His microbiologist mother and architect father temporarily sacrificed their careers to help with the family farm when his Japanese grandparents returned from internment after World War II.

It was clearly a sophisticated, multicultural farm life, however, one in which Nagano could become proficient on piano, clarinet, viola and koto before high school. He also put them all aside for electric guitar in the pop-crazed world of high school.

Nagano was enough of a product of the social and political unrest of the late ‘60s and early ‘70s to have vacillated between music and social science while an undergraduate at the University of California, Santa Cruz. He did eventually, as a graduate student at San Francisco State University, choose music.

But his real start toward a music career began when he took a job as an assistant to Sarah Caldwell at the Boston Opera, where he learned the opera business from the ground up by doing everything from sweeping the stage to playing in the pit to negotiating labor contracts.

Such practical experience was probably as attractive as Nagano’s nascent conducting ability to the Berkeley Symphony, a fledgling, barely surviving organization, when it appointed him music director in 1978. At his first concert, Nagano remembers that only about 125 people were in the audience, and so financially uncertain was the orchestra that during Nagano’s first four years with it, it had to cancel at least one concert a season, and once almost disbanded. But it also proved an ideal training ground for Nagano, who is remembered as the kid with the ponytail and funky formal clothes.

“When you’re under these kinds of pressures and these kinds of conditions, you learn quickly what is really exciting and what is not,” he says.

What Nagano learned was that it was foolish to compete against the San Francisco Symphony and the Oakland Symphony, so he decided to offer audiences something they couldn’t hear anywhere else. Feeling that he had nothing to lose, he became wildly ambitious, programming such impractical occasions as a cycle of huge Messiaen orchestra works and a concert performance of Hans Pfitzner’s Gargantuan opera “Palestrina.”

It worked for Nagano. Olivier Messiaen noticed and Nagano became a favorite interpreter of the composer.

Conductor Seiji Ozawa also noticed, and Nagano became his assistant at the Boston Symphony, where he won international recognition when he led a triumphant performance of Mahler’s Ninth Symphony on one day’s notice and without rehearsal.

And it worked for Berkeley: The orchestra is now a success story financially and artistically.

“In Lyon we’ve done something very similar over the past seven years--golly, I’ve been there a long time now, five years as music director,” Nagano says of how his Berkeley experiences might have influenced him in Lyon.

As part of the Lyon Opera triumvirate, completed by an artistic director and a general director, Nagano says his mandate is only to do what there is a really good reason for doing. And that kind of thinking has led to innovative productions and recordings that have brought the company a wide international following.

One example Nagano gives is the Puccini cycle with which he is currently involved in Lyon. Puccini, while overdone everywhere else, is actually foreign to the company, which Nagano claims had never before performed “La Boheme,” “Madama Butterfly,” “Tosca” or “Turandot.” But Nagano also feels that the operas profit from a contemporary sensibility, and he is particularly proud of the attention-getting productions of “Butterfly,” directed by Kon Ichikawa with sets by Arata Isozaki (the Japanese architect who designed the Museum of Contemporary Art in Los Angeles) and with a basically Japanese cast, and a “Turandot” directed by the legendary Japanese filmmaker Hiroshi Teshigahara (“Woman in the Dunes”).

These productions, which will tour Japan, also represent Nagano’s continued involvement in his Japanese heritage, something further enhanced by the fact that he has married the Japanese pianist Mari Kodama.

But another key to his success in Lyon, which has been documented on a number of award-winning recordings (including Prokofiev’s “The Love for Three Oranges” and Poulenc’s “Dialogues of the Carmelites”) has been Nagano’s painstaking attention to details, to maintaining utter clarity and first-rate ensemble playing at all times. That has even brought him into the pit for ballet productions. A new video of choreographer Angelin Preljocaj’s “Romeo and Juliet” not only demonstrates the innovative staging and musical solutions that have become typical of Lyon, but also a level of orchestral execution that is almost unknown in ballet.

Given his successes with marginal institutions (Lyon was not in bad shape under his predecessor, the early-music specialist John Eliot Gardiner, but neither was it the venturesome operation it is today), it is hardly surprising that Halle would go shopping for Nagano. What is surprising is that Nagano accepted.

Though once a glorious orchestra under Sir John Barbirolli, Halle had become an orchestra one British critic called “in terminal decline after 20 years of mediocrity under James Loughran and Stanislaw Skrowaczewski.”

But as part of an attempt to boost its image, Manchester had applied to become an Olympic city in 2000. And to make the city more attractive to the Olympic committee, it had thought to upgrade its once great orchestra and to build a new hall for it. It had hoped to match Sir Simon Rattle’s achievement for the City of Birmingham.

Both Manchester and the Halle turned out to be as little known to Nagano as it is for most of us these days. “It’s far away,” Nagano notes. “Most people think of it, I guess, as an industrial base; or even worse than that, many people think of it as a former industrial capital.”

But to Nagano’s surprise he found that Manchester had adapted to its post-industrial situation the way few other cities have.

“It’s beautiful, and the air is clean. The buildings are spotless. There is a lot of new construction. That image of a dirty old decaying industrial city just doesn’t ring true anymore.”

Not only did Nagano find that Manchester seemed a worthwhile place to settle for a large part of each year, he was also impressed by the civic support for the orchestra, since the city continued right along with its plans for the new hall even after it lost its Olympic bid. He also found that the orchestra had a tradition that felt just right for him.

“And you’d be surprised what that tradition is,” Nagano exclaims with enthusiasm. “It’s the tradition of the most progressive and advanced thinking both in terms of performance (and) in terms of performance standards. Sir Charles Halle came from an illustrious career in France, where he was very close to composers like Berlioz, Chopin and Liszt. He invited to Manchester all of these people, all of his friends that he knew in Paris, establishing Manchester as a real cultural avant-garde center. It’s amazing.”

The Halle tradition continued with Hans Richter, the great 19th-Century conductor who debuted works by Wagner and Brahms and continued with the likes of Sir Thomas Beecham and Sir John Barbirolli.

“People think of Barbirolli as someone really steeped and immersed in the British literature,” Nagano suggests, “but it just wasn’t true. The fact is that he was recording Mahler when no one else was recording Mahler. He was championing Sibelius when Sibelius was considered radical music. When he played Vaughan Williams symphonies, he was giving premieres--this was brand-new music. Elgar didn’t really have an outlet before Barbirolli championed him. This repertoire that Barbirolli was bringing was on the forefront of musical development at the time.”

And, most notably, that is just what Nagano has set out to do in modern terms in Manchester.

He opened his first Halle season in 1992 with Messiaen’s last piece as well as John Adams’ “El Dorado.” He has greatly involved himself in the orchestra’s educational programs. And the results have already been gratifying, he says, with many, many younger people in the audience and the programs selling out.

The result is that Nagano is now thought of as a major conductor in England just as much as he is in France. And he is sought after everywhere.

The week of the Adams premiere with the London Symphony Orchestra, for instance, also found him in the recording studio, taping the concerto for Nonesuch, squeezed in between other London Symphony recording sessions (part of the Ravel cycle for Erato and a “Boheme” with Kiri Te Kanawa for Teldec). The release this summer of a spectacular new recording with the London Symphony of Stravinsky’s “Firebird” was greeted by the British as an occasion once more for feature stories and a magazine cover.

Through it all, though working day and night in London and coping with singers’ illnesses and cancellations in the “Boheme” sessions, Nagano seemed cool.

At the Adams recording session he listened as intently to the wishes of the composer and violinist Kremer as he did to the orchestra. And when Kremer would want to repeat something to get yet another perspective, Nagano’s quiet diligence kept the overworked orchestra alert, the soloist and composer happy, the studio atmosphere collegial.

The music bloomed. Very few loud conductors can do as much.

* Kent Nagano conducts the Halle Orchestra, Tuesday through Saturday at 8:30 p.m. at the Hollywood Bowl.