"I always felt I was doing something wrong," recalled Nigerian composer Adam Fiberesima of his student days in London a generation ago. "I was going to engineering classes during the week and playing jazz on weekends."

But it wasn't long before he had a pivotal experience that convinced him which way to go. "I went to a party," he remembered, "and there was a piano there that everyone seemed afraid of."

But Fiberesima wasn't awed. He attacked the piano with a flourish. At this roaring conclusion, a woman asked him what he did. When Fiberesima replied that he was studying engineering, she exclaimed: "You're an artist. You look like an artist, you walk like one and you behave like one."

Fiberesima hasn't looked back since: He switched from the Lewiham College of Technology to Trinity College. And today, more than 20 years later, Fiberesima is one of Nigeria's leading composers - a major force in the school of composers who draw upon that country's folk music.

Several of the camposer's works will receive their American premiere tonight in a concert by the D.C. Youth Orchestra in Baird Auditorium at the Smithsonian's Museum of Natural History.

The pieces are "Wind of Change," a symphonic suite, the Overture to his opera, "Opu-Jaja," and two works for piano and voice, "Idegebeani" and "Ozu-Kombo." Also included on the program are compositions by Eubie Blake, David Diamond and George Walker.

Fiberesima, 51, is in this country on six-week State Department-sponsored tour. He has been listening to orchestras, meeting his composer-counterparts and making an occasional speech.

A compactly built man who smiles easily and speaks softly in a clipped Anglo-Nigerian accent, Fiberesima likes to talk about the tradition of musicians in which he falls.

The practice of Nigerian composers using folk elements in formal settings is relatively new. Of the six composers in the line, Fela Sowanda, who teaches at the University of Pittsburgh, is the oldest at age 74.

"You can go to the libraries now and get our music," said Feberesima, "and this is the thing we're trying to project. We want to have our music available for everyone. The response has been good."

Rhythm, perhaps the most distinctive quality in any African music, is the element that is most novel in Fiberesima's adaptation of folk forms to Western European contexts. The composer said he frequently uses the hocket rhythmic approach - a rapid alteration of two voices with single notes or short groups of notes.

"I remember many years ago when it was hard for English orchestras to play the rhythms in my music," Fiberesima observed.

At Thursday night's rehearsal, the D.C. Youth Orchestra had difficulty with a passage where the time abruptly changes from 4/4 to 6/8.

Said Orchestra Conductor Lyn McLain: "His music sings, so to speak. The rhythms aren't particularly difficult once you get the hang of them. The kids like his music. Nigerian folk songs - it's another exposure for the kids."

Fiberesima, head of the music department of the Nigerian Broadcasting Corp., has seen his works performed by the Royal Philharmonic in London and the Warsaw Philharmonic. He doesn't think he's experienced the difficulties black American composers have in getting their works performed.

After attending the recent weeklong program of works by Afro-American composers by the New York Philharmonic. Fiberesima said he was surprised at what he heard. "They're good," he remarked. "The stand up there with the best - even the masters."

But, he said, "What is hampering the black American composer is that he hasn't come out in full and demonstrated that he wants to write serious music. He's not quite sure that his music will be accepted."