Lambert Daniel Karsten, the leading organ builder in Scandinavia in the 18th century, was commissioned to build a new organ. In the 1720s, he created a monumental baroque organ with 46 stops, the largest in Scandinavia at the time. Although none of the pipes remain, Karsten's beautiful baroque facade from 1727 is still in use.
By the early 1990s, it was clear a comprehensive organ plan was needed for the cathedral. The standard of the then-main organ was very poor. While a small organ was built in 1985, it was too small to serve as a full accompaniment instrument. Thus, it was decided to build a new choir organ and a main organ.
The Norwegian firm Ryde & Berg A/S was chosen to build the organs. The new main organ, with 53 stops, was inaugurated for the cathedral's 300th anniversary in 1997. The design of the old baroque facade influenced the new instrument's aesthetics, both in craftsmanship and sound. The challenge was to build an instrument that belonged to Karsten's baroque facade without being a strict stylistic copy. The new organ blends Nordic classical tradition with versatility, capable of expressing a wide range of organ literature from the 18th century to today.
The main organ consists of 53,000 parts and approximately 3,600 pipes, requiring a year of work by eight to ten craftsmen.