CHICAGO -- One coconut, some wood and a little horsehair would not a Stradivarius make, but in the right hands they can make for a decent dan gao. And in Vietnam, the dan gao holds some heavy sway.

The dan gao, which sounds a lot like a highly pitched violin, is used for Vietnamese "folk" music, a traditional and ceremonial art form that dates back at least to the 13th century.

While the music is familiar to just about everyone in Vietnam, it's not exactly everyday music in the United States. That is something Bay Duc wants to change.

Bay, 64, a Vietnamese refugee, is one of the "boat people" who left Vietnam in 1983. He spent 15 months in a refugee camp in Thailand before finally making it to Chicago in 1984.

A professional musician in his homeland, he is concerned that Vietnamese youngsters living here have been cut off from their culture and, more specifically, Vietnamese music.

So several days a week, Bay walks up the block in Uptown to the Vietnamese Association, where he gives free music classes and instructions on a variety of traditional Vietnamese instruments to about a dozen Vietnamese students ranging in age from 16 to 20.

And when he's not giving lessons or fishing on Lake Michigan (his other favorite pastime), he's busy constructing his stringed instruments. They hang in a neat row above his bed in his small room in the Harold Washington SRO (single resident occupancy) apartments.

"I play 10 instruments," he says in broken English, also explaining that Bay Duc is his stage name. His birth name is Duc Vo.

With the aid of Hong Nguyen, a young neighbor who acts as a translator, Bay points out the half dozen or so types of instruments he has made and demonstrates how each is played.

There is a violin that is tuned differently from Western violins and is held at mid-chest instead of tucked under the chin. There's a 13-fret dan sen, which has two strings and resembles a banjo in look and sound; and a dan co or "stork," which has a neck like a stork.

The stork is played with a bow, as is the coconut dan gao. The stork and the dan gao also have only two strings, but in Bay's hands they are capable of an amazing range of notes.

Bay says his favorite instrument is also the most difficult to play. It's the 16-string dan tranh, which is held on the lap and emits a sound like an Oriental harp, or what many people would refer to as Japanese tearoom music.

There are several dan tranhs leaning against the walls of the room, and they were all constructed by Bay for his young students. The dan tranh can be traced back to the 13th century and is an essential part of Vietnamese ceremonial bands that perform for rites of passage such as marriage and death.

"Here's a song about missing someone," says translator Hong Nguyen, paging through a book of 200 traditional tunes, all carefully typed by Bay. "Many of these songs are based on fairy tales and some are played at weddings and festivals. But most of it is very serious music. It's like the opera is here {in the United States} except a lot of this is played in the temples. Most of this music is very sad, because it's usually played at funerals."

Indeed, in Chicago, Bay played at a memorial service for Mayor Harold Washington. His other public appearances have included local festivals and a concert as part of an ethnic music series sponsored by Links Hall.

In Vietnam it wasn't unusual for Bay to be on television and radio. But that was back in the days when Ho Chi Minh City was still called Saigon and Bay worked in the Vietnamese Department of Agriculture.

He says what he misses most about his homeland is his son, who is still there with his wife. Bay's two daughters did manage to leave the country. One lives in Chicago and the other in Paris.

"I can never go back," he says, glancing out the window of his room.

He strokes the strings of the dan tranh, keeping alive a little bit of his country in a song.