When the traditional Christmas bells ring out at White House candlelight tours this holiday season, they will be controlled by quick-study musicians from St. Matthew's United Methodist Church in Annandale.

The church has six groups of handbell ringers who have played throughout the country at churches, schools, shopping malls, nursing homes and parties as well as the White House. Yet its interest in this traditional music began only in 1973.

St. Matthew's purchased two octaves of handbells that year and asked one of its two music directors, Nancy Cappel, if she would like to start a group. "I got a book on the subject, and that's how it all began," Cappel said.

Today the church has 85 handbell ringers who are thought to be the most active among such groups at 20 area churches.

The most expert of the church's six groups is the Carol Ringers, composed of 10 Annandale high school students whose range covers five octaves. Each ringer may control up to seven or even 10 bells, holding as many as three in a hand at one time.

Manipulating a 15-pound brass monstrosity that produces low C, Cappel demonstrated the bell ringers' art. "In the English bells," she explained, "the clapper is fixed -- it only goes in one direction. So by turning the bells around and holding them between your fingers, you can get one to ring by pushing your hand down and the other to ring by pulling your hand up."

The bells can be rung, "damped" (stopped right after sounding), "plucked" (by pulling the clapper while the bell rests on a surface), and hit with a mallet.

All of this must be done in rhythm with other bell ringers since bells "are a percussion instrument," Cappel said. "The ringers are not in charge of the rhythm."

Imagine playing your favorite tune on a piano that is missing two notes, and you'll see what happens if one bell ringer messes up. That's what happened to Chris Campbell, a ninth grader from W.T. Woodson High School, when he substituted in a group that played at the White House last summer. "I really stunk out," he admitted. "I was so engulfed in being where all those presidents once stood."

Campbell, who took up bells three years ago, apparently recouped well, because Cappel brought him into the top group.

Cappel said she thinks it takes "six months to a year for a group to solidify" because the teamwork must be precise. "There is no other ensemble work like bells," she said.

Handbell ringing started "several hundred years ago in England" when the men who rang the large bells hung in towers needed a chance to practice in private, Cappel said.

Bell ringing originally meant pulling long ropes to ring the tower bells. It was noisy work, Cappel said, "and every time the ringers made a mistake, the townspeople could hear it."

Ringing then was limited to "changes," that is, all the mathematical combinations of notes the bells intone.

"Then somebody noticed that you could ring tunes on bells," Cappel said, and the traditional music played today was born.

The ringers in Lancaster, England, managed to impress a scout for P.T. Barnum with their music about a century ago, and he brought them to the United States -- "as Swiss Bell Ringers," Cappel said. "I guess Barnum thought bells should be Swiss, so he told the ringers not to talk to the public."

Bell ringing didn't catch on in this country until the 1920s, when a group started in Massachusetts. The ringers had to order their bells from England. No one manufactured bells in this country until the 1960s.

The music available for bell ringers is also quite new. "The original stuff has all been written in the last 10 or 15 years," Cappel said. Her groups do everything from traditional Christmas carols to Scott Joplin's "The Entertainer," including a few numbers that Cappel has arranged.

But most of Cappel's arranging involves booking local appearances -- some 30 performances a year just for the Carol Ringers. The group plays for elementary schools, conventions and Lion's Club meetings and even performs "Bell-o-Grams" for special occasions like birthdays.

In summer, the ringers usually attend the festival of their national organization, the American Guild of English Handbell Ringers. In 1982, they will go to an international meeting in Toronto -- by way of Knoxville. "We hope to play at the World's Fair," Cappel said, "and I figured that would be on our way to Toronto."

But next week they go back to the White House to play during the public candlelight tours on the 29th and 30th, a booking all the members describe as their "high point."