Simulating The Way That Sounds Are Created On An Organ (Tone Wheel) - Roland FP-7F Owner's Manual

Performing

Simulating the Way that Sounds are Created on an Organ (Tone Wheel)

On the FP-7F, you can use the [ORGAN] button to select one of the "TW-Organ 1–6" tones to play tones that simulate the way in which sound is
produced by an organ.
On a tone wheel organ, you can create original sounds by sliding nine harmonic bars (drawbars) forward or backward to change their relative balance.
Each bar is assigned a different footage, and this footage determines the pitch of the sound. 8' is the footage that forms the basic pitch of the sound;
this is the center around which you create the tone.
By assigning the footage to the TONE buttons, you can simulate the way in which these harmonic bars are used to create the sound.
What's the feet?
"Feet" is a term that began as a measurement of the length of the pipes in a pipe organ.
The pipes that produce the basic pitch (fundamental) for each note are considered to be "8 feet" in length.
Therefore, a pipe producing a pitch one octave below that of the reference of 8' (eight feet) would be 16'; for one octave above the reference, the
pipe would be 4' , and to take the pitch up yet another octave it would be shortened to 2' .
The pitches of the harmonic bars are related as follows.
one octave 5th
below
On tone wheel organs, the high-pitched footage for a portion of the high range, and the low-pitched footage for a portion of the low range are
"folded-back" in units of one octave.
Folding back the high-frequency portion prevents the high-frequency sounds from being unpleasantly shrill, and folding back the low-
frequency portion prevents the sound from becoming "muddy. "
On the FP-7F faithfully simulates this characteristic.
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When the middle C (C4) note is pressed,
each harmonic bar will sound the following notes.
root 8th 12th
8' =
15th 17th 19th 22nd