Peking — Sarah Caldwell stood center stage, in flowing white dress trimmed with red and blue, applauding back at the audience that was so enthusiastically applauding her.
The curtain had just rung down on "La Traviata," and Miss Caldwell had been called up from her conductor's seat in the orchestra pit to join the singers on stage.
A Peking audience, notorious for dispersing the minute a performance is over, was standing and clapping and cheering and making no move for the exits despite the long bus queues that await most theatergoers in this country.
Evening after evening the scenes has been repeated during the past week, as an audience deprived of Western opera for 10 long years during the Cultural Revolution (1966- 76) followed with rapt attention the tragedy of a demimondaine who sacrifieced her own fleeting happiness for that of her lover's family.
In the street outside the theater, young folk in white shirts or singlets played cards under the street lamps. A child laboriously penned his characters for the next day.
Old people squatted on stools and chatted. The whole city seemed to be out on the streets, seeking to catch any breath of fresh air in the hot and humid night.
Inside, an audience of the same citizens of Peking -- older ladies with graying hair combed straight back and cut short, young girls in bright blouses and more sober skirts or trousers, men with black plastic satchels showing they had come straight from works, -- savored the opulence of 19th-century Paris salons, thrilled to the melting cadences of Verdi.
If dusty gray is the daily color of Peking, for a space of two hours those of its citizens who love Western opera could revel in the rich variety of tones and colors so characteristic of Verdi's world.
The singers, the chorus, the orchestra, all were Chinese. Miss Caldwell was the only non-Chinese involved in the proceedings -- but her role was crucial.
Director and founder of the Opera Company of Boston, she had been invited, like so many other prominent Western artists, to China as part of the Ministry of Culture's vigorous program of cultural exchanges with the world's leading nations. Before her had come Yehudi Menuhin, Isaac Stern, Seiji Ozawa, Beverly Sills, and many others. "La Traviata" was first performed in China in 1925, said Gu Fang, director of the Central Opera Institute, which is Miss Caldwell's host during her stay.
Even today, the story of the virtuous courtesan strikes a responsive chord in each night's audience.It has been performed over 400 times altogether, and the present version, directed by Zheng Xiaoying, has been delighting Peking audiences since last fall.
Miss Caldwell is enthusiastic about the basic understanding the entire cast and orchestra has of the dramatic meaning of the opera and the training they have received from Mrs. Zheng and Mr. Gu. Her own contribution, she says, was mainly in "phrasing and articulation" and a host of small but essential details. the result is a performance that combines exuberance with restraint and that somehow seems so natural sung in Chinese and when Miss Caldwell gets back to the United States, "it's going to sound funny in Italian," she said.
Every Western artist that has come here in recent years has commented on the hunger of Chinese audiences and performers alike, not only to keep alive their own musical traditions, but to dig deep into the great musical heritage of the West, to keep themselves abreast of the main musical currents of the world.
Miss Caldwell is no exception. She was struck by the willingness of singers and orchestra to "change instantly and spectacularly" one of the things they had been doing before her arrival visit July 3.
She was careful to tell them that her way was not necessarily the only right way, that each conductor had his or her own approach to Verdi's music. She would like to think, she told a group of American journalists tactfully, that some of the singers she worked with had voices of "world class," given further training and experience.
The Chinese have been as enthusiastic about her as she has been about them. They have dubbed her "Miss All-Weather," because of her willingness to work in sweltering heat morning, noon, and night. "She has given us a new, deeper understanding of Verdi," said Mr. Gu. All of us are most grateful to her."