Christa Schönfeldinger playing the glass armonica. (Courtesy of The Kennedy Center/Courtesy of The Kennedy Center)

When mischievous children at fancy restaurants inevitably put wet finger to crystal glass rim, they create a ring that is mostly considered annoying by grown-ups. But the cultivation of that sound, that dates to ancient China and Persia, was refined for chamber music by a busy founding father 15 years before the American Revolution.

In addition to inventing the lightning rod and bifocal glasses and signing the Declaration of Independence and the Constitution, Benjamin Franklin developed the glass armonica. The instrument — a series of glass bowls put on a spindle for easier playing — greatly advanced the “musical glasses.”

A sensation in its time in Europe, where Beethoven and Mozart wrote music for it, the instrument became nearly extinct. But in 1990, Christa and Gerald Schoenfeldinger, a pair of Austrian violinists, who formed the Vienna Glass Armonica Duo, took up the instrument.

This weekend, Christa Schoenfeldinger — who will have traveled by plane to Washington alongside her armonica (“It’s not possible to give it to the normal luggage,” she says) — will perform with the National Symphony Orchestra.

By phone this week from Austria, she spoke of discovering the instrument’s haunting sound because of a newspaper quiz.

Christa Schönfeldinger playing the glass armonica. (Courtesy of The Kennedy Center)

“We read in an Austrian newspaper a riddle. And this riddle was: Search for this instrument, which was very famous in the 18th century, and it had a special sound and Mozart wrote for this instrument. We went to the museum in Vienna and there was a glass armonica. We heard sound examples of this instrument and from this moment — it was 22 years ago — we knew we had to play it.

“It’s really a great invention. Franklin was, because of his political doings, in Great Britain, and there was an instrument very famous called musical glasses. . . . We know for example Gluck played concerts on this instrument. And Franklin heard one of the concerts and after this he invented his glass armonica. . . .

“There are few old instruments remaining, because it wasn’t played for 150 years. . . . After going to the museum, we asked the director of the museum if he knew somebody who built this instrument nowadays. He gave us an address of German instrument builder and we went there. . . .

“We had no possibility 20 years ago to learn the instrument by a school or by a teacher. I had to learn the glass armonica by myself. . . .

“There always has to be a little water on the glasses. If there is no water . . . there would be no sound. Also, I have to wash my fingers before playing the instrument. Because if there is any dirt, or the normal oil of skin, there is also no sound.

“It’s really hard to describe, because the sound of the glass armonica is very special. In every concert when I look to the audience it’s really different what happens when I play the glass armonica than when I play the violin. Maybe because it’s a very ethereal sound, and it’s a very relaxing sound, and it’s a sound you can’t imagine is an instrument built from glass can do this sound.

“You cannot produce this sound by a synthesizer or something like that. It is the secret of the glass armonica. I can’t explain it to you. But if you hear it live onstage, it’s really different to all other sounds. . . . People [who] hear the glass armonica, after five or 10 minutes, look like children, really loving, very happy. If you allow me to say it, this sound goes directly to your soul.”

Christa Schoenfeldinger will join the National Symphony Orchestra on a piece she helped introduce, “Armonica” by Jorg Widmann, who also will perform at the concert as featured soloist on Mozart’s Clarinet Concerto. Christoph Eschenbach will conduct the program, which also features Schubert, at the Kennedy Center for the Performing Arts, 2700 F St NW, 8 p.m. Saturday and 3 p.m. Sunday. Tickets are $20 to $85. For information, go to or call 800-444-1324 or 202-467-4600.

Catlin is a freelance writer.