Most significant changes in the structure of the instrument were made during the interwar period. Between 1934 and 1935, Gdańsk organ builder, Joseph Goebel extended the organ to 4 manuals and added a new electro-pneumatic tracker action with wind chests. He used 51 registers from those already existing, renewing some of them and adding some new ones. Moreover, he connected the choir organ to the main console. After completion of the work, the Oliwa organ had 82 standard registers and 5 transmitted ones.
