User manual

OVERTONE & MULTIPLY
If you follow the gold wires from the outputs of the OSCILLATOR Circuit, you
see that the Triangle and Square waves are wired to the OVERTONE circuit
(Figure 40), where the Square waveform is used to add an OVERTONE to the
Triangle waveform (you might have noticed that the SLOPE is also routed to
the OVERTONE circuit, more on that in second half of this manual). This wired
Connection between the OSCILLATOR and OVERTONE circuits allows for
shaping the timbre of the 0-COAST.
OVERTONE adds sound that is higher in frequency, yet still
harmonically-related to the Fundamental. In order to hear the eect, return the
0-COAST settings to the Default Sound and then set the BALANCE control Full
CW, so that you are only hearing the Overtones. Hold a key on your controller
or set the 0-COAST to Drone (refer to Figure 9, Page 8). Slowly turn the OVERTONE Panel Control Clockwise and listen for the
change in the timbre of the sound as the single Overtone fades from ODD to , which is a transitional state, to EVEN and
nally to
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where the SLOPE circuit is blended into the audio signal path. To hear the SLOPE in the audio signal path set
SLOPE to CYCLE and set RISE and FALL to 9 o' Clock for Audio rate SLOPE generation. Set OVERTONE Full CW. This will create a
very inharmonic sound, not unlike a Ring Modulator, unless you tune the SLOPE to the Oscillator.
Follow the short gold wire from the OVERTONE to the MULTIPLY circuit:
This indicates the wired connection of the signal from the OVERTONE circuit to the MULTIPLY circuit where that single
Overtone is multiplied, thus creating additional Overtones and a more harmonically-rich sound. Set OVERTONE to EVEN
and then turn the MULTIPLY Panel Control slowly Clockwise until it is Full CW. You may be able to distinguish each new
Overtone slowly increasing in volume as you turn the MULTIPLY Panel Control Clockwise. This is the opposite of what
happens in a Low Pass Filter: the East Coast synthesis circuit commonly found in mono-synths. Rather than starting with a
waveform that already has many harmonics, such as the Square wave, and
subtracting them from that signal using a Filter, the MULTIPLY circuit
ADDS Overtones to a waveform that has few harmonics, Figure 41.
This primitive addion technique is an important part of West Coast
synthesis.
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Figure 40: Typical Normalization Label
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Figure 41:
OVERTONE: Harmonic MULTIPLY Panel Control
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