12 tonewheels of 64 teeth
12 tonewheels of 128 teeth
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-In the patent organ the number of teeth on the tonewheels change at F instead of C as in the production organs. Also note that there are twice as many 16 toothed tonewheels as the other octaves. This required two different sets of GearRatio''''s
that changed at F3 to make this odd arrangement of tonewheels work correctly. There are no tones above the sixth octave like there are in the production organs because the hobbing machine used to cut the sinusoidal "teeth" in the tonewheels could not cut 256 teeth. Hammond didn't solve this problem until just before the Model A was introduced (see Early Model info below).
+In the patent organ the number of teeth on the tonewheels change at F instead of C as in the production organs. Also note that there are twice as many 16 toothed tonewheels as the other octaves. This required two different sets of [Gear Ratios|
GearRatio]
that changed at F3 to make this odd arrangement of tonewheels work correctly. There are no tones above the sixth octave like there are in the production organs because the hobbing machine used to cut the sinusoidal "teeth" in the tonewheels could not cut 256 teeth. Hammond didn't solve this problem until just before the Model A was introduced (see Early Model info below).
!!! Early Model 91 Frequency Generator
The following organs were produced from the mid 1930's to the early 1940's and have a 91 frequency generator:
