Ludwig van Beethoven is known to have purchased instruments from Nanette Streicher, and she ran the composer's household for many years.
Upon completing his apprenticeship with Nanette Streicher, Grimm returned to his hometown of Spaichingen in 1819 and began building virginals.
[1][2] Grimm's successor was his nephew Carl Sauter, who built the workshop into a factory employing a dozen apprentices in 1846, becoming a prominent instrument manufacturer in the region of Swabia.
Johann traveled extensively, including to America, researching contemporary instrument construction in advance of the company's transition from manufacturing virginals to building the larger, more complex and expensive pianoforte, the predecessor to the modern piano.
In addition, Sauter supplies many of the parts that are used to manufacture the custom-made Ravenscroft piano by Michael Spreeman.