HOOSICK, N.Y. -- For some of the harpsichords Walter Burr has repaired over the past 30 years, he gathers crow feathers from his own back yard. The quills pluck the strings when a musician presses the keys of this precursor to the piano.
For the past three decades, Walter and his wife, Berta, have specialized in crafting working replicas of antique harpsichords, as well as smaller instruments including the clavichord and virginal, out of their home. Now semi-retired, the Burrs focus almost exclusively on instrument restoration.
Clients have asked them to clean, touch up and retune antique keyboard instruments as well as the odd harp.
"It's been the ideal cottage industry." Walter said.
Profit and recognition accompany their passion. Con temp orary musician Peter Watchorn used one of the Burr's commissions, in the style of Andreas Rucker's' 1640 harpsichord, when he recorded a CD of classical pieces at Southern Ver mont College.
The Burrs have studied the musical collections of museums across Europe. They have become self-taught, internationally recognized authorities on the restoration of antique instrument. As a result, they have reconnected contemporary listeners to the centuries-old music that came out the Netherlands and France.
The couple has musically restored and made copies of 17th-century harpsichords and virginals for the Smithsonian; their work with the museum cumulated in musician Charles Metz playing one of the Burr's replicas for a recital in 2010.
"We celebrate occasions like this," Walter said. "We often hear about our results but (do not often get to hear) the finished product."
His musical career began at age 10, when he became a boy soprano. After leaving the Eng lish program at SUNY Buffalo, Burr spent his early 20s at a company that built organs. However, he soon set off on his own and shifted his focus, because it took a team to complete an organ, but one dedicated craftsperson could assemble a harpsichord.
This career move coincided with a worldwide revival of appreciation for the harpsichord, whose popularity initially flourished during the Baroque and Renaissance periods.
"Everyone wanted to own one. Business was booming, and we became seven years behind on orders," Burr said.
He selects Swiss mountain spruce and basswood for the cases. Along with imported ebony, he shapes cow bones from dairy farms into keys. Hunters send him crow feathers, which musicians find respond better than the modern substitute of nylon.
Along with their dedication to the traditional process, the Burrs have an acute awareness of changes in technology.
"But as far as we're concerned, very little about harpsichords has really changed over the centuries," Walter said.
Berta completes the rebirth of the instrument by adorning the surfaces with ornate artwork. She has drawn and painted since her youth and, like her husband, she has a background in classical music from her studies at SUNY Buffalo.
"I fell in love with music and him at the same time," she said. "We've benefited from each other ever since."
An attraction to antiquity drives Berta. Her landscapes decorate the lids, and she adorns soundboards with birds and flowers. Using techniques similar to those the Egyptians perfected two millennia ago to burnish surfaces, she applies 1/2000 of an inch of gold leaf -- merely replacing an agate polishing tool for the original dog's tooth.
She finds real gratification in transforming each artifact back into something that a musician can play for an audience.
"When you work on something made by a dedicated craftsman long ago, you develop an intimate rapport," she said.
Walter speaks enthusiastically on the lineage of related keyboard instruments, whose mechanisms of play speak to the evolution in Western music. The couple's accomplishments include a 1790 grand piano by the frontrunner of American makers, John Broadwood; in transforming it from relic to instrument, the Burrs traced the fusion of English and German craft.
Thanks to the Burrs, of the earliest harpsichords in playing condition -- originally made in 1539 by Florence Geronimo before the advent of sheet music -- now lives in Troy, N.Y.
Berta also paints, and she sells antiques with her husband, but she relishes taking part in the restoration process.
"I've had the most serendipitous of career convergences," she said. "Whenever we do this, I feel like I'm fulfilling the intention of a longtime friend."