Fokker organ

photo of Fokker-organ

History

After 1945 Fokker continued musical composition and other musical activities. He concentrated more and more on tuning theory, especially in relation to just intonation and 31-tone tuning. He began a larger enterprise of instrument building, namely an organ with the full scale of 31 tones per octave. He secured enough financial aid for its construction, and the organ - of his own design - was installed in Teyler's Museum in 1950. It is now usually called the "Fokker organ". It has a main console with two 31-tone manuals and a pedal keyboard, and an additional console with 12-tone keyboards on which portions of the 31-tone scale can be played. The first organist was Paul Christiaan van Westering. The first concert on the new organ was given on 10 September 1951, with compositions by Jan Pieterszoon Sweelinck, Paul Christiaan van Westering and Jan van Dijk. Concerts involving the organ took place frequently during the period 1951-1955, featuring both newly-written 31-tone music on the main keyboard and early music on the meantone option of the additional, 12-tone keyboard. Since then concerts were given on each first Sunday of the month, except in January.
The disposition of the organ is
Manual I C-g''' (143 tones, 319 keys): Quintaten 8', Prestant 4';
Manual II C-g''' (143 tones, 319 keys): Salicionaal 8', Chimney flute 4';
Pedal C-f (45 tones and keys): Sub-bass 16', Stopped flute 8' (transm.)
Couplings: (P + I); (P + II); (I + II). Pitch: a' = 440 Hz.
The disposition on the additional console with a normal 12-tone keyboard is the same, except in the Pedal. Because it has one octave more, Stopped flute 8' was left away. The 12-tone keyboard is connected to the organ in a special way. By means of nine push buttons nine 12-tone selections out of the 31 tones per octave can be connected to the manual. Eight of them are fixed and for one tones can be selected at random with switches. The fixed selections are Euler-Fokker genera with fifths, major thirds and harmonic sevenths making scales with 12 tones per octave: [3³.5²], [3².5³], [5³.7²], [3³.7²], [5².7³], [3².5.7], [3.5².7], [3.5.7²]. In the programmable selection the meantone scale can be set, with E and G. It provides the notes as used and conceived by the 17th and 18th century composers and it thereby restores the ancient beauty of their creations. As Fokker said: "this is the console looking back to the classical past." The other console with the 31-tone keyboards is "the console looking to the future."
The organ was removed from the museum in 2000 and is now in temporary storage waiting for a new location.

For sound examples of the Fokker organ, go to the CD-page.

 

Keyboard

color photo of the Fokker organ

Schematic representation of the keyboard design of the Fokker organ.

A.D. Fokker: About the construction of the 31-tone organ


Literature

Photos after the renovation