W. Ritmüller & Sohn AG was a piano manufacturer originated in Göttingen, Germany.
In the late 18th century, Andreas Georg Ritmüller and his son, Gottlieb Wilhelm Ritmüller (1772-1829),[1] began production of lutes, guitars, and harps in Göttingen.
[2] In 1795, the production of piano began in their workshop, and after the father's death in c. 1800, the company was officially named "G. W.
"[2] Two sons of Gottlieb Wilhelm Ritmüller, Johann Wilhelm (born 1802) and Johann Martin (born 1803), joined the company.
[3] With changing owners and partners, the production continued in Göttingen and later in Berlin.