A RUSSIAN WINTER FOR THE ARTS : Musical Exodus From Troubled Russia : * Music: The list of recent migrants constitutes virtually every composer of world renown. ‘Almost anybody with talent is getting out.’

In the most sweeping musical emigration since the Russian Revolution of 1917, many of the country’s top composers have fled a collapsing society for more hospitable lands.

Among the latest to join the ranks of fleeing musicians were two leading young composers, Dmitri Smirnov and Elena Firsova, a married couple whose home was the center of Moscow’s contemporary music scene. Claiming that in Moscow they could no longer feed their children, the couple recently received special permission to live in Britain.

Their emigration means that now nearly all of the country’s top composers are living abroad:

* Alfred Schnittke, 56, one of the most distinctive voices since Shostakovich, now lives in Hamburg, where surgeons have helped him recover from heart attacks and a brain tumor.

* Sofia Gubaidulina, 59, the country’s most celebrated living woman composer, is in a small German town where she can compose undisturbed.

* Edison Denisov, 52, the veteran modernist, spent a year in Paris before settling in Switzerland.

* Rodion Shchedrin, 58, a pillar of orthodoxy, and Valentin Silvestrov, 54, a noted Slavophile, have teaching posts in Germany.

The Russian contemporary music scene has been decimated by the exodus. In addition to Smirnov and Firsova, the composer-pianist Vassily Lobanov has settled in Germany. Leonid Grabowsky is in the United States. Nicolai Korndorf lives in Canada. Sascha Ivashkin, the scholar and concert organizer, has fled to New Zealand.

“Almost anybody with talent is getting out--writers, painters, musicians,” said Gerard McBurney, a British composer who has lived in Moscow. “The intelligentsia is fleeing just as it did in 1917.”

Smirnov and Firsova, both 41, are among the most recent musical emigrants, but their reasons for leaving had roots established long ago: bureaucratic politics and the failure of the economic system.

“Moscow was dangerous for the health of my children,” said Firsova of Phillip, 6, and Alisa, 5. “There was no good food. No meat, no chicken. For milk, Dima went out five times a day. Every two months the children had problems with teeth. Now they have very good teeth.”

When the family first came to Britain, they faced an uncertain future until a concert fan, Christopher Tew, wrote to his member of Parliament, who procured permission for them to live in Britain for three years.

Treasury Secretary David Mellor, a well-known music lover, also interceded on their behalf. “I can’t claim much of the credit,” said Mellor. “I was willing to do much more.” Despite British government policy to bar economic refugees, the rules are often relaxed for celebrities.

When Firsova and Smirnov’s British visa expired last October, the two composers traveled to Columbus, Ohio, to participate in weekend conference on Russian music. Smirnov’s First Symphony, conducted by Gunther Schuller, was performed during the four-day conference.

The family has received assurances that their three-year permits to live in Britain are approved. They expect to spend three months in residence at St. John’s College, Cambridge, and have been given free accommodation for a year at Dartington College, Devon.

“After that we don’t know exactly what we shall do, but we have many commissions and should have enough money to live,” Firsova said.

Her choral work “Augury” will be premiered at the BBC Promenade Concerts next summer and Smirnov has just written an oratorio for the 1993 Leeds Festival. Firsova has extensive credits from opera to cinema music to works for voice and ensemble and has been frequently heard in the West. Both composers’ works were represented in a U.S.-Soviet Composers’ Conference in Los Angeles three years ago.

They expressed concern that the next generation of Russian composers has been left without means for survival. Composers cannot get their works adequately performed because the best orchestras are absent on dollar-earning tours, Smirnov complained. When he booked an orchestra from Gorki to play his Second Symphony, the musicians flew home in mid-rehearsal, complaining that Moscow hotels were sub-standard.

“Everybody thinks about the unstable political and economic situation,” Smirnov said. “This is no time for music.”