IT'S NOT just black composers who are suffering," said pianist Natalie Hinderas, "it's living American composers generally, although it's worse for black composers. Somebody should tell the foreign conductors who come over here and direct American orchestras that they have a duty to give some attention to American music."

Hinderas, one of the most distinguished black classical performing artists in the United States, was at the Kennedy Center last week to give master classes as part of the National Black Music Colloquium and Competition. Her remark, which came up during a post-concert conversation with composers Ulysses Kay and Talib Rasul Hakim, pinpointed one of the problems discussed most often during the week-long colloquium: Composers depend on performers to have their music heard, and in classical music (unlike pop music and jazz) black composers and instrumental performers both have a low profile. The problem dates back at least to the time of Scott Joplin, who earned wealth and fame writing ragtime and died (some say of grief) trying to get an opera produced. When it was finally staged, more than half a century after his death, that opera, "Treemonisha," was a smash hit.

This situation has improved since Joplin's time, but black composers still say they face even more serious problems than their white counterparts; white conductors, ensembles and soloists seldom perform music of black composers. "It's not a matter of policy," says Hakim. "They just don't know us or our work." Composer-pianist George Walker, who has made it about as far into the mainstream musical establishment as any black composer, explains that "black composers do not belong to cliques, which have a lot to do with determining what music gets a hearing."

A few black performing artists have won international reputations -- mostly singers or pianists, but black conductors and players on strings or other orchestral instruments are just beginning to gain acceptance. Walker explained wryly that motivation to study certain instruments has been traditionally low because the prospect of a job in a good orchestra was dubious at best. "Playing in an orchestra is a social experience," he said.

In spite of such obstacles, Ulysses Kay said he was happy to see the high quality of workmanship by the young black performing artists in the colloquium. q"In the past," he said, "we used to lose so many younger performers to popular music and jazz."

Part of the problem is undoubtedly psychological, black musicians feel. Americans (more than people in Europe, where classical music originated) tend to make an artificial distinction between black music and classical music -- although the first American classical composer to make an impact in Europe, Louis Moreau Gottschalk, did it with what was essentially black music. It still considered unusual when a black performer achieves distinction in classical music, despite the long and rapidly growing list of those who have done so: singers such as Roland Hayes, Marian Anderson and Leontyne Price; pianists Like Andre Watts, Leon Bates and Natalie Hinderas; conductors such as Dean Dixon, James De Preist, Henry Lewis and Paul Freeman. This mind-set may be changing somewhat; younger conductors such as Lewis and Freeman have been able to build their careers in the United States, while Dixon performed almost entirely in Europe and De Preist made his reputation there before coming back to work first in Washington and later as director of L'Orchestre Symphonique de Quebec.

Acceptance of blacks in American popular music dates back to the turn of the century, when Joplin's sheet music for "Maple Leaf Rag" sold over a million copies. A few years later, hard times hit Storyville, the red-light district of New Orleans, and the musicians who had worked there began moving up the river to Chicago to make a living.

Until the New Orleans diaspora began spreading jazz across the map and the world began going crazy for ragtime, America's culturally approved popular music was still oriented toward Europe. Songs like "She's Only a Bird in a Gilded Cage" or "After the Ball," with their narrative verses and lyric choruses (which are usually the only parts now remembered) were recognizable descendants of the recitatives and arias of European opera. Perhaps the swan song of this era was "Meet Me In St. Louis, Louis," since the St. Louis World's Fair of 1903, which was its subject, was the place where a lot of the world found out about a form of music called ragtime which was specially strong in Missouri.

While it was conquering the popular field in America, black music caught the imagination of classical composers in Europe. Debussy and Ravel, Milhaud and Stravinsky were among those who found new ideas in the strange sounds coming from America and tried them out in their own music -- and many others began to follow their example, notably including Gershwin in America. A lot of the distinctive flavor in American music of this century has been derived from black music -- even when the composer is white.

The black performers who are beginning to make an impact in the mainstream of American music did not spring out of a vacuum. They are largely a product of a vigorous black classical musical life which has been going on in churches, colleges and women's clubs virtually unnoticed by the white community except when it produces a Leontyne Price or a Marian Anderson.

"New Orleans has a particularly strong tradition of black presence in classical performance and composition, dating all the way back to the time of Gottschalk," said Cliff Johnson, an educator and maker of documentary films. "But you can find similar traditions wherever a black community has reached a level of prosperity and education sufficient to make it possible -- particularly around college campuses and black music schools. All of us studied an instrument, and some stayed with it -- like the artists we have been hearing at this colloquium."

A number of southern colleges that were founded by and for blacks have strong opera programs, and some of them have graduates singing in the opera companies of Berlin and Vienna. Particularly notable in this field during the '70s has been Opera-South in Jackson, Miss., which is sponsored jointly by three black colleges, emphasizes the music of black composers and has given several world premieres. But this is relatively recent, as is the Harlem Opera Society, founded in 1960, or even the National Negro Opera company, which was founded in 1941, launched the careers of such singers as Camilla Williams and McHenry Boatwright, and survived a long series of financial crises until the death of its founder, Mary Cardwell Dawson, in 1962.

The history of black participation in American opera goes back at least to 1873, when the Colored American Opera Company was founded in Washington, D.C. Probably the first all-black symphony orchestra in the United States was formed in 1839, when conductor Frank Johnson added strings to an existing military band for the purpose of playing classical music.The career of Hall Johnson helps to illustrate what happened to black instrumental musicians. In the early 1920s, he was the violist in an organization called the Negro String Quartet; then in 1925 he founded the Hall Johnson Choir (which specialized in spirituals) and became one of the most acclaimed choral conductors of his time. The talent goes where the encouragement (particularly financial encouragement) leads it, and black musicians singing spirituals obviously could find audiences that were unavailable to black musicians playing string quartets.

The same kind of attitude affected the works of black composers, particularly in the first half of this century. The pioneer composers of black classical music found more encouragement for works with such titles as "Juba Dance," "Magnolia Suite," "From the Delta," "Afro-American Symphony" and "Levee Dances" than for abstract quartets, sonatas and symphonies.

The colloquium indicated how substantially this situation has changed. All the music presented was chamber music and the prevailing trend was toward abstract, classical forms with little indication (or exploitation) of black folkloric elements. In overall quality, the music presented at the colloquium was at least equal to comparable festivals of recent memory -- less inclined to dry academicism than "establishment" programs and quite a bit more solid in form and lyric in impulse than the "experimental" programs of counter-establishment musicians.

In some ways, the isolation of black composers from the cliques and fads that have dominated much contemporary music has probably done them good. Natalie Hinderas summed it up well, after warning that what she said was a generalization, when she said that the music being produced by black composers has "a healthiness and integrity" not always found elsewhere.

"It has a message and a meaning," she said. "There is a strength of communication in black composers that moves audiences when they hear it. Give it a chance, and it can help to revive what is happening on the concert stage."