"It's the oldest two manual, that's two keyboards, and the largest surviving organ from any 18th century American builder," says Owen.
And it wasn't built by just any builder. The historic organ was constructed by David Tannenberg -- the American who is to organs what the Stradivarius label is to violins.
For more than a century, the Tannenberg organ was a beloved member of the congregation. They even held a party to celebrate its centennial.
But a decade later, when it began to falter, the Tannenberg was retired. The passing was noted in the church's diary: "June 24, 1910. The old organ, which for more than a century has done such splendid service, was removed today..."
"If the Moravians hadn't been such a bunch of pack rats and put things in attics, you know we would never have this wonderful organ," says Barbara Owen. "Many organs from that period are simply gone."
Then again, the organ had a guardian angel.
Paula Locklair works for Old Salem, a historic restoration of 18th century Salem, North Carolina. The village was already blessed with a smaller Tannenberg on display, but the 1800 two-keyboard -- stored in pieces around town -- was legendary.
"It was a big financial commitment for Old Salem to raise the money to restore the organ," recalls Locklair. "Not just restore it, but supply a place for it."
The restoration would cost $600,000 and the new auditorium to house the organ cost another $3 million. But money alone couldn't buy the exacting research required. Poring over the minutiae would be a labor of love.
George Taylor and organ builder John Boody of Staunton, Virginia won the commission.
"We're trying to save every bit of the original voicing of the organ," says Taylor.
They'd restored a Tannenberg in the past and that knowledge came in handy to re-assemble the 1800 Tannenberg.
"There is no living person that has ever seen this organ assembled," says John Boody. "We have to kind of find our way as we're doing the restoration.
"The original keyboards of this organ were lost, and we have to recreate these keys."
All but 17 of the organ's original 644 pipes had survived. The first hurdle was straightening out damage done by some long-ago Boy Scouts who apparently had a field day squashing them.
Next, they reversed an alteration – all the pipes were cut short -- that raised the organ's pitch in the 1840s.
To get back the authentic Tannenberg sound, each pipe had to be painstakingly lengthened.
"We're trying to recreate an ancient alloy, so we've analyzed very old organ pipes," says Boody.
That required creating historically accurate sheet metal in the Taylor and Boody workshop.
"It's been quite an experience learning a different type of voicing from the old pipes," says Taylor. "It's like having a new teacher."
Since the 1800 is a mechanical organ, pressing a key involves many pieces. Each element had to be meticulously repaired. As a wind instrument, no sound could be made with wheezy lungs.
Unhinging the creaky old bellows was like opening a time capsule. Tannenberg had used whatever paper was at hand for the lining: sermons, pages from Catechisms, newspapers such as a notice from then-president John Adams.
"[The papers] had been out of the light for 200 years," says Taylor.
Elsewhere, a note about an earlier repair was found.
"It says, 'Re-leathered: April 10,1885,'" recalls Taylor.
Also, the old organ held mementos from other folks who wanted to be remembered.
After working for more than a year, the restoration team finished. The 1800 Tannenberg was moved back down to its home in North Carolina.
For the world of historic organs, the restoration of the 1800 Tannenberg was a milestone. Hundreds of aficionados congregated in Old Salem to celebrate.
Peter Sykes a virtuoso of old music, went to play at the rededication ceremony.
"Some of the pipes take a tremendously long time to bloom," says Sykes. "You can't play very fast and it makes the player slow down and listen."
Like proud parents at a graduation, the organ builders took turns pumping the bellows -- breathing life into the organ as they sent it off into a new life.
"No matter how smooth an electric machine is, it's not quite the same as making the organ breath itself," says Boody.
It was a glorious sound from the past.