Hammond SKX, Reference Manual

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Drawbars & Percussion
70
CUSTOM TONE WHEEL Edit Menu - WHEEL
This Advanced Feature Menu Page allows you to change of the characteristics of all 96 tone wheels individually.
What Is “Generator Calibration?”
Because each frequency on a Hammond Organ is generated independently and the circuitry and hardware necessary to
generate each tone is quite complex, there is the potential for a great deal of variation in sound from one frequency to
another.
The above diagram shows how a single frequency is generated. As explained on page 25, there is one tone wheel for each
frequency. The number of tone wheels which generate actual frequencies varies with the model. Organs based on the
original Hammond design - the model A and its derivatives (B-3, C-3, etc.) had 91 tone wheels that sound, while later
models such as the “H” series and the X-77 had 96 (the extra five tone wheels being used to generate higher frequencies).
As explained previously, each tone has a magnetized rod associated with it. When the tone wheels rotate, a very small
electrical current is generated in the coil each time a high spot passes the magnet. The strength of the current determines
the loudness of the resulting musical note.
At the Hammond tone-wheel factory, the distance of each magnet to each tone wheel - as well as the number of windings
for each coil - was very carefully controlled to insure that each frequency would play at the correct volume. In other
words, the generator on each tone-wheel organ was very carefully
calibrated . However, a number of third-party
technicians would re-calibrate generators to change the sound in various ways - make the sound brighter, etc. The
CUSTOM TONE WHEEL Advanced Feature Menu allows you to “re-calibrate” the digital tone wheels of your
instrument to create exactly the tone quality you desire.
NOTE: In order to use this Advanced Feature, you should already have some idea of the type of sound you want.
Also, you should be prepared that getting the results you want may require some “trial-and-error” before you are
satisfied with the results.
HA<O> SKX
Owner’s Playing Guide