Georg Wilhelm Wilhelmy (born 1748 in Weißenbach, North Hesse; died March 1806 in Oldendorf) was a German organ builder who initially worked in North Hesse and then from 1781 to 1806 in Stade. Wilhelmy, originally named Georg Wilhelm Wilhelm, was baptized on January 11, 1748. He learned the organ building trade from his older half-brother, Georg Peter Wilhelm, who became the court organ builder in Kassel in 1771. When his brother moved to Kassel in 1766, Wilhelmy took over his workshop in Weißenbach and added an "i" and later a "y" to his last name to avoid the redundancy of his first and last names.

In 1781, Wilhelmy moved to Stade with his family to repair the organ at St. Cosmae et Damiani. He became an admirer of the Baroque organ builder Arp Schnitger and influenced the organ landscape between the Elbe and Weser rivers, focusing on maintaining and caring for Schnitger's instruments. Wilhelmy was soon one of the most sought-after organ makers in the Duchies of Bremen and Oldenburg. His new constructions were exclusively in Schnitger's style, making him a bridge between the Baroque and Classicism periods. Today, he is considered a key figure in the transition from the Baroque to the Classical style, continuing to build North German Baroque organs into the late 18th and early 19th centuries.

Most of Wilhelmy's instruments have been lost to fire or changes in taste over time. The possibly last surviving organ by Wilhelmy is located in the St.-Gallus-Kirche in Altenesch-Süderbrook. When Wilhelmy died during renovation work on the organ in Oldendorf in March 1806, his son, Johann Georg Wilhelm Wilhelmy, took over his workshop.

https://de.wikipedia.org/wiki/Georg_Wilhelm_Wilhelmy