In the Choir of the Oude Kerk is an organ which was built in 1960 by Flentrop. It was originally a gallery organ that was built by J.M. Garstenhauer in 1791. Flentrop made a new wind chest with action and wind system. Also, the lower part of the case was made in 1960. The roof of the organ case was no longer closed properly and much dirt entered into the case. The panels of the back were completely disintegrated and it was not possible to lock the case anymore. The result was that the entire choir organ was highly polluted by debris and dust.The historic pipe work was already years in a very bad state, the tuning collars were torn, soldered joints cracked, and leaking seals of the hats. This causing the to been never in tune. Technically, the organ was still in reasonable condition. The key coverings and the pivots of the action were worn out and ivory key coverings were largely disappeared. Restoration: the works carried out by J.L. van den Heuvel Orgelbouw were: Inventorisation of the pipe work and all characteristics, the wind pressure and original pitch were determined. In the autumn of 2003, the pipes and large parts were removed and packed. Subsequently, these parts were shipped to the work shop in Dordrecht after which they were being cleaned and restored in style. During the period that this work took place, both the main organ and the choir organ of the Oude Kerk were crated during the restoration work of the church. In February 2004, the choir organ could be uncrated and the organ builders could continue in the church. Pipe racks of the Flentrop windchest were completely overhauled and repaired. Also the Flentrop slider system with spinged double sliders were checked and where necessary springs were added. After restoration, the pipes were replaced, additional pipe rack support were installed to ensure a vertical and stable pipe placement. The valves were cleaned, where necessary releathered and the valve springs adjusted. Then the bellows were cleaned and serviced. Roller boards and action as well as pivots were checked and where necessary replaced.Wind ways were serviced and completed in existing style. Then the blower, the suction valve and the wind regulation overhauled. The organ case The back doors of the organ and the frameworks were uneven and shut very poorly or not. In consultation with the client the back wall of the organ was renewed in historical style. The cabinet work of the sidewalls and the front was in very poor condition. The entire organ case was restored using traditional methods and then painted overall. The gold leaf of the carvings was restored and partly renewed. The lips of the façade pipes were fitted with a new layer of 23.5 carat gold leaf.The voicing was checked and improved. The organ was tuned in the orginal pitch.
