The organ builders Bätz-Witte of Utrecht were active from 1739 to 1902. Johann Heinrich Hartmann Bätz (1709-1770), from Frankenroda in Thuringia, came to the Netherlands in 1733 to work with Christiaan
Müller, under whom he worked on the new organ for the Sint Bavokerk at Haarlem. Johann Heinrich Hartmann Bätz established his own workshop in Utrecht in 1739. Five members of the Bätz family, spread across three generations, directed the Utrecht company until 1849. It was then taken over by the foreman Christiaan Gottlieb Friedrich Witte (Rothenburg, near Hannover, 1802 – Utrecht 1873), who had married into the Bätz family in 1839. His son Johan Frederik (1840-1902) continued the company until his death.
Certificate of competence of J.H.H. Bätz (1733)
The organ builders Bätz-Witte built about 60 instruments, mainly in the west, middle and north of the country, but also in Batavia and Paramaribo. Working to high standards of craftsmanship and artistry, their instruments - more so than those of Smits - form a reflection of contemporary taste. The tonal scheme of the Bätz-Witte organs is largely determined by their primary function in accompanying Protestant congregational singing.
Part of the firm's archive, including many drawings, is preserved in the Utrecht Organ Archive. In addition to case designs, there are construction drawings for the outside and inside of various instruments. The highly detailed technical drawings are executed in colour in order to elucidate the construction. Several case designs are also in colour (including marbling), though for decorative purposes. In addition to drawings, the archive includes nearly 50 building specifications and technical calculations for more than 20 instruments. Most other material is of a more general nature, such as a list of organs, the certificate of competence of J.H.H. Bätz, the license to carry the Royal Arms (1851) and various documents on scaling. This part of the archive also includes contracts, festive speeches, correspondence and reports from journals and newspapers (often in the form of cuttings). Finally, there are many plates covering the architectural orders, crowns and stairways, and some 48 standardised case designs.
Bätz organ formerly in the Remonstrantse Kerk in Utrecht and now in the R.C. Franciscus Xaveriuskerk in Amersfoort (1819)(l)
Case design Hervormde Kerk The Hague (1881)(m)
Part of the contract with the Hervormde Kerk at Beneden-Hardinxveld (1875)(r)