Johannes Klais Orgelbau GmbH & Co. KG, based in Bonn, is a leading organ-building workshop in Germany with an export rate of about 40%. The company, founded in 1882 by Johannes Klais (1852–1925), is now in its fourth generation. Initially located on Breite Straße in downtown Bonn, it moved to a new residential and operational building on Kölnstraße in 1894, designed by Gerhard Franz Langenberg, which was occupied in the spring of 1896. Johannes Klais’s son, Hans Klais (1890–1965), took over in 1921, followed by his grandson Hans Gerd Klais (* 1930) in 1965. Today, the company is led by his great-grandson, Philipp Klais (* 1967).

Klais’s new organ constructions typically follow the concept of the universal organ, aiming to merge stylistic elements from different organ epochs and regions into a cohesive, contemporary design. This includes modern designs for the organ's facade, casing, and console, while also incorporating innovative developments.

In 1975, the company garnered international attention for the restoration of the bamboo organ built in 1824 from the parish church of St. Joseph in Las Piñas, Philippines. This unique, deteriorating instrument was flown in pieces to Bonn and meticulously restored. Klais has also restored many other historic organs.

Hermann Simon mentions the Klais organ company in his book as an example of a "Hidden Champion."

https://de.wikipedia.org/wiki/Johannes_Klais_Orgelbau
https://klais.de/