CLASSICAL MUSIC aficionados with an interest in the turn-of-the-century Romantic period might recognize the name Mrs. H. H. A. Beach (after her husband Dr. Henry Harris Aubrey Beach) and remember that she was the first American woman to compose a symphony -- the "Gaelic" Symphony, Op. 32, written in 1895. But Amy Beach was far more prolific. She wrote cantatas, church music, a one-act opera, chamber music, piano pieces and songs. Her first major work as a composer was the Grand Mass in E flat major for soli, chorus, orchestra and organ, which was first performed by the Handel and Haydn Society under Carl Zerrahn in 1892 at the Boston Music Hall.

Charles W. Stone, secretary of the society, wrote in the program that the Mass was "beautiful, brilliant and strong. A work of such magnitude by a woman makes a positive addition to the history of music; and its approaching production will not only be an event of capital importance in the musical life of the city, but will have a far more than local interest and significance."

Sunday afternoon at 2:30, Beach's Grand Mass will be performed in the Concert Hall at the Kennedy Center by the Mrs. H. H. A. Beach Festival Chorus and Orchestra, conducted by Michael May. Why, after years of relative obscurity, has this piece suddenly surfaced at the Kennedy Center in Washington and been scheduled later this month at New York's Carnegie Hall? The answer in part, according to May, who seems to be one of the composer's biggest admirers today, is because Beach was a woman.

"The very thing that once prevented her from being well-known is helping her now," May explains. And this notion goes beyond gender. "The attitude people used to have was to hide their background," he says. "Now it's changing. We don't want to melt into the mainstream. We want to celebrate our uniqueness. There is a new ethnic awareness, a new pride in the music of blacks, Jews, the Irish. And this change of attitude on the part of the public is instrumental in making them interested in Beach."

Amy Marcy Cheney (1867-1944), an only child and musical prodigy who grew up in New England, received much musical encouragement at home. Not only was her mother a singer and pianist who first taught her daughter to play piano, but her husband, Dr. Beach, was an amateur musician. Outside the home, however, music was still "a man's world," says May, who is writing a biography of Beach. "She met with a good deal of prejudice. Women in music were not taken seriously. Did you know, for example, that women were not even allowed to be in the New York Philharmonic until the 1950s?"

"Women didn't take as much interest in achievements of women as they do now," May says. Today there is a group called the Presidents' Committee to Recognize and Promote Women in the Arts -- a fledgling organization made up of about 25 men and women, all presidents of various companies and associations, and headed by T. Jean Feldman of New York -- that hopes to sponsor performances of little-known works by women artists. It is this group that is largely responsible for facilitating the Beach revival concert on Sunday.

"It's a miracle!" says May. "Last March I was conducting the Mass at a small Methodist church in Shrub Oak, N.Y. Terry Feldman , who has a country home in the area, was at the concert, heard the piece, and decided that her group should promote it." May held auditions in New York and New Jersey and organized the large chorus to perform it -- thus, The Mrs. H. H. A. Beach Festival Chorus and Orchestra. He even had a special portrait of Beach painted for the "joyous" occasion.

"Beach has a lot to contribute to us now," he says. "Her music is the happiest, the wittiest . . . What she tried to capture was a sense of wonder in everything, beauty in everything. She has a unique voice which has too long gone unheard."