The year was 1948. Maxim Shostakovich was 10 years old. His father, Dmitri Shostakovich, perhaps the greatest composer in Soviet history, had been denounced -- along with such other leading Russian composers as Prokofiev and Khachaturian -- as an enemy of the people.
Young Maxim stood at a window in the family dacha outside Leningrad, as people walked by hurling insults: ''Shostakovich is an enemy of the people! Shostakovich is a formalist!'' (''Formalist'' was a term concocted by the Soviet musical hierarchy to describe almost anything modern or futuristic in serious music.)
''I had to memorize and answer questions in school about what dreadful music my father wrote,'' he recalls of that time. ''It was tough.''
According to many musical scholars, this moment represented a turning point in the history of Russian music. And it certainly was one for Maxim Shostakovich.
Until then, his father, along with Prokofiev and others in the Soviet Union, were exploring the boundaries of modern music. They were young firebrands forging a new Russian musical idiom. All of that changed, however, after the crackdown of 1948: The great Russian experimenters became, for a long dark period, little more than inspired copyists.
Dmitri Shostakovich went on to become the Kremlin's model composer, making the required speeches at conventions, writing less adventurous compositions, keeping silence in the face of official coercion - the Composers' Union wields widespread control over the livelihoods of Soviet composers. Although much later in life he wrote a few defiant, towering modern works, and his son says he used his music as a wordless protest against the repression of the Soviet system, Shostakovich never fully recaptured the momentum and promise of his early career.
In a way, son Maxim's decision to slip away from a concert tour in Western Europe last year began way back in 1948, when his family first came face to face with the ugliness of Soviet repression. From that time forward, he says, he became highly conscious of events surrounding his father's official life. He also remembers quite well the long list of other Russian artists victimized by the state.
Today, he sits after a rehearsal in Boston's Symphony Hall, going quietly through the list of those who he says were ''broken or wounded'' by the muscle of the state:
''The writer Zoschenko.
''The poet Akhamatura.
''Many others, like Solzhenitsyn, whom I knew well.''
This list, he says, and his own father's bitter experiences, made it impossible for him to stay in the Soviet Union.
''My departure was not merely a decision to change circumstances that offended me personally, but a statement of consensus with people like my father whose effort was a protest against the circumstances of repression in which they found themselves.''
There are clues as to what these circumstances were. Little things that one doesn't recognize at first, such as the photographs of the Shostakovich family and friends one sees in biographies and musical reference books. You look at them a dozen times, studying the faces, reading the captions. Then it dawns on you: No one is smiling.
In almost every picture, there is a collection of somber faces, usually staring away from the camera, as if diverted by some private sorrow.
''It's true,'' says Maxim Shostakovich. ''Not much to be happy about.'' But he seems to have plenty to be happy about these days.
Last April he slipped quietly away from a banquet in his honor with his son, Dmitri, a young pianist now studying at Juilliard, and sought asylum in a West German police station. After a lengthy, emotion-charged telephone conversation with a KGB operative and two of his compatriots in the orchestra, he permanently disconnected himself from his Soviet past.
''What happens when you leave the Soviet Union,'' he says, ''is an intense, profound, emotional liberation and emancipation. I feel completely different.''
On the podium in Symphony Hall here during rehearsal, he seemed to be enjoying both the considerable firepower of the orchestra and his own newly found ''emancipation.'' He threw himself into the music; during one explosive passage in a Weber overture, he fairly danced with excitement.
Shostakovich is young, intense, dressed in casual Western slacks and open-collared shirt. He bears an unmistakable resemblance to his father; but the pervading expression is different. The defeat and despair so prominent in Dmitri Shostakovich's features are not evident in his son's.
During an interview, he talks freely about life in the Soviet Union, giving a picture of a system where artistic skills are identified and looked after from a very early age with ''training of a highly professional nature,'' but where ''the human and spiritual needs'' of an artist are given little nourishment.
''This is a very deep issue,'' he says, adding that the whole question of a ''spiritual'' side to music ''involves a deep split in the minds and hearts'' of teachers and officialdom; and the degree to which individual students are nourished with this spiritual view of music depends very much on how close they are to their teachers, and the teacher's own views.
''Shostakovich was my spiritual teacher. He never sat me down to learn, but he was my spiritual tutor, who formed my musical and world outlook.
''Shostakovich spends a lot of time these days thinking about spiritual issues. ''(Religion) has a very great significance for me,'' he says. ''I might not go to church much. But I think about it a lot.''
This thinking began long ago in the Soviet Union, where, he believes, many musical artists share his interests in religion but ''have been forced to become accustomed to'' life in an atheist country. ''Right now, I am delving more deeply into these questions.''
He is also delving deeply into music; but the subjects of music and politics are closely joined in his mind. They are the twin reasons he has come to the West.
Despite a relaxation of musical censorship that began in the regime of Khrushchev, he was prevented from playing music with themes that have special significance to Russian religions. This meant that he could conduct Bach's B-minor Mass and Mozart's Requiem but not Rachmaninoff's Vespers, for example. He was also prevented from playing music with texts considered repugnant to Soviet ideologues, as well as much modern music.
The net effect of these restrictions, he has said, is to create a wall of isolation around Soviet composers and conductors.
Today he is absorbed in the music of the West, learning as he goes. Some American musicians have found him incredibly adept at performing his father's work, but less accomplished in the classical Western repertory. But with his obvious drive, he is already acquiring a solid reputation around the country.
He denies that his father's talent was ''strangled'' by Stalin, as some musical scholars have concluded.
''On the contrary, it made him more angry and more defiantly determined to fight through his music. Shostakovich fought with his music. This was his weapon. He was wounded very deeply and directly. But he was not broken. I was wounded indirectly. But the fact that I am here means that my spirit was not broken. Otherwise, I would be sitting back in Russia with my hands in the air.
''I want the Western world to pay close attention. They should not take the problem of totalitarianism lightly.''
Anyone who listened closely to Shostakovich's Fifteenth Symphony as performed by the Boston Symphony Orchestra, with his son at the podium, got this message indelibly imprinted in the music.
For much of his professional career, Shostakovich was forced to write ''happy'' music which portrayed people as joyously engaged in the great proletarian struggle. Even if a woman in an opera were carrying a 900-pound sack , he once complained, she had to look happy.
In the Fifteenth Symphony, written at a time when he had gained greater freedom of expression, Dmitri Shostakovich composed an ironic piece of musical rhetoric. It begins with all the forced gaiety the musical hierarchy might have wanted, but soon introduces a theme of deep tragedy, which gradually consumes everything.
This symphony is a stirring, stormy work -- all fire and pathos and terror. During the performance Maxim Shostakovich seemed to stand at the epicenter of its mysterious grandeur, completely at home in the temperament and melancholy of the composer.
The obligatory note of ''triumph'' in this symphony is filled with dread sorrow. This is Shostakovich's final answer to the supreme Soviet: a musical landscape filled with grief and lies and murder. And, as his son conducted this blast furnace of a work in Boston, there seemed to be more than music in the air. There seemed to be the sound of unquelled defiance.