Let’s break down what is going on:
The channel has as its input a sawtooth wave with an amplitude of
-/+5V
coming through
a fully open VCA. This waveform gets summed with the
+2V
coming from the offset knob,
resulting in the
main input
of MOD ( ).
On the channel, the only signal is the
+4V
coming from the offset knob, producing the
voltage threshold
of MOD ( ).
Both offsets effectively mix together (
+2V
+ 4V = +6V
) and, starting from the bottom of
the waveform (
-5V
) they set the
actual voltage threshold
level
(
+1V
)
at which the
step size
voltage kicks in and
substracts -1V
from the signal, making it fall back to
0V
. As the
sawtooth wave continues to rise, this process repeats three more times (
four steps in total
)
and then the signal keeps rising unaffected until the end of its cycle.
As we’ll see in later examples, different input signals and patch settings will drastically
change the final result, from voltage-controlled waveshaping to bit-reduction/fuzz and
distortion.
To be clear, in this example the voltage threshold level and the step size voltage appear to
be the same thing because they share the 1V level dotted line by coincidence, but
they are
very different and separate parts of this circuit
and in other patch examples their voltage
levels will differ from one another.
Sequence / DC manipulation:
Here we have a 16 step sequence (
0 to +4V
, C minor scale, root =
0V
) as the channel’s
main input, therefore acting as the
main input
of MOD ( ).
On the channel, the only signal is the
+3V
coming from the offset knob, producing the
voltage threshold
of MOD ( ).
SIGNOS
- User Manual | Page 9
+3V offset
(voltage threshold)
(main input)
0 V
+4 V
X INPUT
Fully open VCA
(original
sequence
OUTPUT
)
0 V
-1 V
MOD OUTPUT
(16 step sequence, C minor scale)
(altered 16 step sequence, chromatic scale)
Step size voltage = -1 V
Root (9th step) = 0 V
Root (9th step) = 0 V
(original sequence
inverted OUTPUT
)
