Chippmann Omega-PhiCS-8 Series, Руководство пользователя

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CS-8 Series Omega-Phi Rev1.04, Oct. 2015
-16-
PM
Phase-Shifter SUM
Polarity
0°
VCA
Σ
+5 V
-5 V
Index
Depth
green/red
-1
180°
+5 V
-5 V
Phi
Phi limit
VCO core
Omega
Triangle
Sine
50% sub Rectangle
Sawtooth Phi
Fig. 3b Structure of the phase-shifting section
Fig. 3a and 3b showing the complete structure of the oscillator. Now, step by
step all parts of it will be described in the following chapters.
8.2. The e-function-generator
An e-function-generator (Exp-Generator, Fig. 3a) is mostly part of every music
VCO. They have a linear input and the exponential input. The linear one is
scaled Hertz/Volt and the exponential one in octaves/Volt or decades/Volt.
Generally, for resulting voltage output U
C
one obtain the mathematical
expression:
ࢁ
࡯
ൌ ࢁ
࢒࢏࢔
∙
∙
࢙࢛࢓
, where α is an exponential scaling-factor and
U
sum
the total input voltage at the exponential input (following called e-input)
and it is the result of the following parts. First of all there are the Scale-
switches.
Scale -switches: The 3-position toggle switch ( upper, lower, LFO ) determines
the range of the 4-position-rotary switch. In position "lower" the lower row of
frequencies of the rotary switch will be output by the VCO core (no further
control voltages applied) in steps of octaves 55 Hz, 110 Hz, 220 Hz and 440 Hz.
In position "upper" it is the upper row also in octave steps 880 Hz, 1760 Hz,
3520 Hz and 7040 Hz. In position "LFO" the oscillators frequency at "55 Hz"-
position of the rotary switch and at full CCW (counter clockwise) of the
Tune
-
controller is about 0.08 Hz.