Sweet strains of summer. Aspiring cellists, bassoonists, violinists gather in Greensboro for the Eastern Music Festival

FOR six weeks every summer, kids with calloused finger tips and heads full of glorious music transform a quiet campus into a festival. Grand pianos arrive at Guilford College by truck, and the deep bur of cellos lingers around buildings of old brick. Renowned classical performers - the likes of cellist Yo-Yo Ma, trumpeter Wynton Marsalis, violinist Josef Gingold, and flutist Ransom Wilson - perform, instruct, and discuss musical ideas.

The occasion is the Eastern Music Festival - and the reason for the festival is its young students. The professional musicians who perform at the Eastern Philharmonic Orchestra come first of all to teach.

``I think we could make the argument that the Eastern Philharmonic is the finest performing orchestra between Washington and, say, St. Louis,'' says music director Sheldon Morgenstern, who founded the festival 26 years ago. ``But there would be no reason for that group to exist here without students.''

Sitting on the steps of the auditorium between rehearsals, they look like teen-agers anywhere, dressed in T-shirts and flowered shorts, some with spiked hair.

But these 183 students, aged 12 to 20, aspire to the intensely competitive world of professional classical music. To prepare, they perform weekly in orchestras and chamber music groups, take private lessons from one of 80 faculty members, and study musical theory. Their regimen is six days a week, and it is tough.

``Take Monday,'' says 14-year-old Adam Davis, a cellist from Orange, Conn. ``I have orchestra from 9:30 to 12:30, sections from 1:30 to 3:30, master class from 4 to 6. Then there's a piano recital I want to hear after dinner. Then string chamber orchestra practices from 9:45 to 11:30.''

Not much time in that schedule for ``Miami Vice'' reruns.

``No one would dare not practice and go to a section rehearsal,'' says violinist Susan Gilson, 17, from West Hartford, Conn. She is referring to the session where all players of each instrument meet to work out the difficult passages in the music.

The special guest artists who perform with the festival live on the Guilford College campus for about a week, conducting master classes with individual students in an auditorium open to the public. In these classes artists critique performances, give interpretive suggestions, and help students find the best wrist and finger positions.

When Wynton Marsalis, winner of five Grammy Awards, gave a master class in 1985 to a student performing a movement that Mr. Marsalis had recorded, 400 people attended.

Students are selected for the festival by competitive auditions throughout the United States and Europe.

By requiring them to perform a new orchestral work every week, the summer program gives students a taste of the life of a professional concert musician. Students performed half of the 40 symphonies, chamber music concerts, recitals, and community mini-concerts held this season in this city of 185,000.

``A lot of the concerts are very close to professional-level concerts,'' says Robert Helmacy, conductor of one of the two identical student orchestras. ``We have so many talented and highly advanced students that we can do pieces that they wouldn't get to do in their youth orchestras at home.''

On the stage of a dark auditorium, 90 kids warm up violas, oboes, flutes, and French horns, sounding the weird, atonal wails of an orchestra coming into tune. A girl in cutoffs and sweat shirt blows a low, round note on her bassoon. Empty, velvet-lined instrument cases are heaped on the sides of the stage.

Mr. Helmacy takes his place before them to a sudden alert silence.

``I know you're excited about tonight's performance, but what I'm asking you to do this afternoon is get some rest,'' he says. ``Don't practice.''

Then his baton rises and falls, and the first notes of Beethoven's Symphony No. 3 fill the auditorium.

``There is no limit on our repertoire,'' says Carl Roskott, conductor of the sec-ond student orchestra. ``We don't have to scale it down for them.''

Mr. Roskott, a winner of two Leonard Bernstein Fellowships, allows the students to premi`ere orchestral works he composes.

``They play at such a level that they give a very good reading,'' says the conductor, who has been at the festival for 20 years, first as a student and now as a member of the faculty.

``I might get a more polished performance [from professionals], but they benefit. It makes them feel very important and special.''

Many of the festival's 3,000 alumni - who are represented in every major orchestra in the United States - feel continuing commitment to the students.

Randall Hodgkinson, for example, artist-in-residence at the New England Conservatory, has taught on the piano faculty of the festival for five years. And Marsalis funded a full scholarship this year for a minority trumpet player.

``If you ever want an extra lesson from anyone on the faculty, you just have to walk over and say, `Would you please give me an extra lesson?' and they'd do it,'' says Susan Gilson. ``Most of them live right here in Bryan [Hall], which is really neat.''

When pianist Michael Chertock first came to the festival at age 15, he had never played with an orchestra and didn't know how to count measures.

``Some conductors would have like to have yelled, but Mr. Roskott said, `Come over to my apartment,' and he taught me on his own time,'' recalls Michael, who is now a conservatory student at the University of Cincinnati.

``It's a homey place,'' says Adam Davis. ``I think the atmosphere is the thing that really makes the EMF.''

Music director Morgenstern says the atmosphere of the festival is deliberately supportive. By mixing students of all ages in two orchestras of equal accomplishment, rotating first seats among all students, and offering small chamber music performances, the faculty hopes to deemphasize obsessive competition.

``We try to remove the competitive atmosphere while they're here, because it's tough enough outside,'' Mr. Morgenstern says.

Indeed, many of the young musicians are relentlessly self-disciplined, placing far more pressure on themselves than any adult would ever ask. Music ripples on the campus from sunup until last curfew at 1 a.m. There is a music stand in the bathroom of the auditorium.

``Last year I practiced 13 hours a day,'' comments bass trombone player Darrin Milling, 19. ``That's the way I am. When I start practicing, I keep going.''

It is difficult enough for many teen-agers to express themselves without hours of solitary practice each day and notes continually echoing in their heads.

``I think we express ourselves differently from normal people,'' says 18-year-old Angela Jones, a violinist from Tobaccoville, N.C. ``Playing gave me [a kind of] voice to get me used to dealing with people better.''

``When I'm in school I try to act like a normal person and fit in, but I think there's a difference in personality,'' says Adam Davis, an apparently self-assured boy. ``It's different from anywhere else here because people have a strong common interest. My friends are closer here than my friends at home.''

This common interest in music draws together students, faculty, and some 45,000 classical music lovers, who drive from all over North Carolina and southern Virginia to attend the concerts each year.

The festival is consistently ranked as one of the top six music festivals in the US. Contributors make up 32 percent of its yearly budget, which is just over $1 million. Nearly half of the budget is made up from ticket sales and students' tuition and board of $1,800.

The students are big fans of every concert.

``People are sometimes kind of repressed about showing their feelings, but the students are really great,'' says Hodgkinson, who can still remember the first concert he heard when he was a student at age 13. Whether the performers are famous artists, teachers, or young musicians, he says, students attend every performance, whistling and stamping and shouting their approval.

``They give the place its energy,'' says Sheldon Morgenstern. ``That's a good way to put it.''