"Most Russians didn't really have a chance to know the true Italian school," Ms. KAZARNOVSKAYA, who is 35 and was born in Moscow, said in fluid, ebullient English in her apartment on the Upper West Side of Manhattan as her 20-month-old son Andryusha provided an obbligato of polyglot babble. "They were singing in the Soviet tradition, like all the Russian sopranos in the 50's and 60's, and thought they were the best in the world. But it was awful. The poor people didn't know how to produce the right sound. Very rarely, we heard something like the tour of La Scala in the 70's with the young Caballé and Domingo.

"Only because of glasnost, perestroika and the breaking of the Iron Curtain, we started to hear what's going on in the West, to relearn style and languages," she continued, mourning the prerevolutionary golden age, when Moscow and St. Petersburg were international opera centers and sopranos like Nina Koshetz, Felia Litvinne, Medea Mei-Figner and Antonina Nezhdanova were jewels in the czar's crown.

Ms. Kazarnovskaya attributes her success to an unusual background. The daughter of a philologist and a military historian, she enrolled at 16 in Knessini College in Moscow to study with Nadezhda Malysheva, an accompanist of Fyodor Chaliapin, who drilled her in Italian vocalises and art songs. Three years later, she went to the Moscow Conservatory to work with Elena Shumilova, a Bolshoi diva who had studied exclusively with Italian teachers.

At 22, Ms. Kazarnovskaya made her professional debut, as Tatyana at the Stanislavsky Theater in Moscow, where she also sang Puccini's "Bohème," Gounod's "Faust" and Verdi's "Battaglia di Legnano," all in Russian. "Until a few years ago," she said, "we didn't sing Western operas in the original languages."

The next year, Yevgeny Svetlanov invited her to make her Bolshoi debut in "Onegin." In 1986, Yuri Temirkanov chose her for the Kirov's new production of Verdi's "Forza del Destino," and she remained a company stalwart until 1989.

. . . In 1989, just before the collapse of the Soviet Union, Ms. Kazarnovskaya was forced to leave Russia because of her marriage to a Viennese agent, Robert Roszyk. He helped her make connections in the West, and before long she was busy working with conductors like Daniel Barenboim, Charles Dutoit, Bernard Haitink and Riccardo Muti.

. Ms. Kazarnovskaya's menu is . . . eclectic. After her recital, she will take part in concert performances of Verdi's "Trovatore" with the Israel Philharmonic, sing Vitellia in Mozart's "Clemenza di Tito" in Buenos Aires and return to the Kirov for Strauss's "Salome."

"I told Valery that I will do Salome my way," she said. "I will not scream at all. It's not music for screaming; it's raffiné. You have to sing beautifully, sexily."

She also eyes roles like Charlotte in Massenet's "Werther," Adalgisa in "Norma," and Bizet's Carmen, all normally considered mezzo-soprano territory. "The color of my voice is very much like a mezzo," she said, noting that Russian soprano roles and Western mezzo roles have practically the same tessitura.

While Ms. Kazarnovskaya revels in the new political and artistic openness, which made possible her return to her homeland and the Kirov, she points out its potential pitfalls. "The new generation of Russian singers has the opportunity to perform in the West," she said, "so if they've started a nice career in Russia, they want immediately to go to the West, because it's very important to be known there. It's a big plus but maybe also a minus, because sometimes they're not growing, they're not really prepared. Also, now there are perhaps too many people from Eastern Europe in the West. And maybe if they go too early, they'll lose the Russian style.