Pipe organ in Große Kirche, Pipe organ in Große Kirche, Leer, Germany

The organ of the Große Kirche in Leer has 48 stops on three manuals and pedal since Hendrik Ahrend's restoration, completed in 2018. Twelve stops are wholly or partly historic, some going back to the 16th century. Its case, with baroque carving by Albertus Antonius Hinsz (1763–1766), now has two Rückpositive on the left and right, added by Paul Ott in 1953–1955.

The organ's history begins at Thedinga Monastery, for which Andreas de Mare probably built an instrument around 1570. In 1609 Count Enno III gave it to the Reformed congregation in Leer, and Marten de Mare moved it to the old Liudgeri Church. Albertus Antonius Hinsz rebuilt it in 1763–1766 with a new baroque case, and in 1787 Johann Friedrich Wenthin transferred it to the present church, built in 1785–1787.

The organ's oldest pipes date from before 1609, when Marten de Mare reworked them for the Reformed congregation; twelve registers are wholly or partly historic. The instrument moved in 1787 with the congregation into the new church built 1785–1787, where Johann Friedrich Wenthin reordered its small pipes. Since the 2018 restoration by Hendrik Ahrend it has 48 registers on three manuals and pedal, the largest organ in East Frisia.

The organ stands on the east gallery of the Große Kirche, built 1785–1787; the free-standing console from Paul Ott's 1953–1955 rebuild faces the nave. Since Hendrik Ahrend's restoration, completed in 2018, the instrument has 48 stops on three manuals and pedal. Look for the two flanking Rückpositiv cases that Ott added left and right of the main organ.

Twelve registers survive wholly or partly from before 1900, some pipes made before 1609 by a builder of the de Mare family and reworked by Marten de Mare that year. In 1917 the tin-rich front pipes, weighing 227 kg, were removed for armaments and replaced in 1924 with zinc pipes by Klassmeier.