B-8 VCO with waveshaping
X is V/Oct pitch input
Y is waveshape/PWM
Z is tune ±0.5 octaves or sync
A & B are selectable output waveforms
Receives MIDI
Parameter Min Max Default
Description
0
-16 8
0
Octave shift.
1
0
32
32
Sets an attenuation for output A.
2
0
32
32
Sets an attenuation for output B.
3
-32 32
0
Offset for input Y (manual shape control).
4
0
4
0
Selects output waveforms.
5
-12 12
0
Transpose.
6
-51 50
-51
Fine tune/enable sync.
This algorithm is a VCO with a 1V/octave pitch CV input (X), and waveshape/PWM input (Y).
The 0V point for the pitch input is C3 (approximately 130.81Hz).
The Z knob/CV provides a tuning control, with a range of approximately ±0.5 octaves (but see also
parameter 6, below).
Parameter 4 selects the output waveforms according to the following table:
Parameter value WaveformA
WaveformB
0
Triangle/saw Square/pulse
1
Triangle/saw Sub-octave square
2
Square/pulse Sub-octave square
3
Triangle/saw MIDI gate.
4
Square/pulse MIDI gate.
Input Y controls the waveshape of the output signals. Signals in the range ±5V give the full range of
possible waveshapes:
Input Y
-5V
0V
+5V
Triangle/saw
saw (falling)
triangle
saw (rising)
Square/pulse
0% duty cycle pulse
50% duty cycle pulse
(square)
100% duty cycle pulse
The output signals are ±8V (16V peak-to-peak) by default, but can be attenuated via parameters 1
and 2.
Parameter 3 offsets the Y input, effectively providing a manual shape control if required.
Parameter 5 transposes the VCO pitch, in semitone increments.
Parameter 6 controls the function of Z. At the default value of -51, Z is the tune control as already
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