Cambridge, Mass. — Nadia Boulanger, the renowned French musician born a century ago, placed her unique stamp on 20th-century music. For not only was Boulanger, who died in 1979, an accomplished keyboardist and the first woman to conduct such major orchestras as the New York Philharmonic and the Boston Symphony Orchestra, but she was first and foremost a teacher who inspired a vast cross section of musicians. Many agree that her greatest gifts, whether in music, human relationships, or life itself, were her enormous enthusiasm and insight, her ability to perceive, in a flash, the heart of the matter.
Boston pianist Rowland Sturges says, ``There's only one word for her: genius.''
Now Boulanger's work is being commemorated in a two-week retrospective festival at the Longy School of Music here.
The festival, which began Sept. 16 on the centennial of her birth, includes the presentation of a documentary film and a symposium and master class. But at its heart is a series of performances featuring Longy's own distinguished faculty and guest artists, such as the noted contralto and Boulanger pupil Eunice Alberts, performing the music of contemporary composers Boulanger influenced and historic composers she revived and revered.
The final weekend will feature the Faur'e Requiem (Sunday), which she conducted at the London premi`ere in 1936, and a Woodwind Quintet (Sept. 26) that composer Elliott Carter dedicated to her.
The connections between Boulanger and the Longy School run deep. In 1921, the young teacher was virtually unknown outside her native France when Melville Smith, who was later the Longy's director, became her first American pupil.
Mr. Smith wrote to composers Virgil Thomson and Aaron Copland about his find and set off a flow of American composers to Paris, who then enriched the stream of American music through her influence.
Later, during World War II, Boulanger lived in Boston, teaching at the Longy School and Harvard University and lecturing at Wellesley College.
Luise Vosgerchian of the music department at Harvard says knowing Boulanger was a seminal experience: ``I came away with a profound sense of quality in everything that governs daily life. She believed that for every mundane task, whether baking a cake or washing a floor, the quality and intensity of involvement should be the same.''
Composer Harold Shapero of Brandeis University recalls, ``I never met a musician like that. Her musicianship was so dazzling. With her, I started all over again. She knew about the notes, the bare bones of the music.'' Yet her ultimate ``magic'' was in ``the intensity of her dedication - her insistence on perfection, discipline, and authenticity.''
Despite several biographies and the documentary film ``Mademoiselle'' (shown last week at the festival and being repeated next Sunday), Boulanger's unorthodox approach as a teacher still is not well understood.
Composer Daniel Pinkham points out that a Boulanger ``school'' never existed, that she never imposed a style but instead encouraged the student to ``find his or her own likes and interests, to develop an individual musical personality.''
Ms. Vosgerchian adds, ``She believed ultimately in her students, saying, `I simply throw seeds when I teach, and I wait to see who picks it up. Those who do are the ones who will do something.'''
Remaining events in the festival include music by Copland, Arthur Berger, and Irving Fine tonight at 8; music by Arthur Honneger, Poulenc, Darius Milhaud, and others Thursday at 8; music by Louise Talma, Elliott Carter, Mozart, and Stravinsky Saturday at 8; the Faur'e Requiem and a screening of ``Mademoiselle'' Sunday at 8.