Instruo SCION User manual

SCÍON
Quad Random Voltage Generator
/ Biofeedback » CV
User Manual

2
Contents
3
Description / Features
4
Installation / Specifications
5
Overview
6
Stimulation
8
Sensitivity
9
Density / Raw Signal Output
10
Channels
12
Modes
16
Patch Examples

3
Description
The SCÍON is a biofeedback sensor built into a quad random voltage
generator. This design is based on the MidiSprout by Datagarden
(https://www.midisprout.com/)
It translates biofeedback data, sourced from contact with organic
surfaces, into musically useful control signals. Tiny fluctuations in surface
conductance on organic materials stimulate control voltage and gate
signal changes that can be used to modulate and permutate your patch.
Dynamic control over biofeedback sensitivity allows you to quickly
adapt any input source to a useful range of responsiveness.
Apply the sensor pads (included with the SCÍON) to your house plants,
your own skin, or even attach the sensor clips to your pet (only if it is
willing). When no sensor cables are used simply touching the capacitive
Leaf electrode with your finger will create random voltages derived from
life itself.
SCÍON offers the ability to make music with all living things.
Features
• Four random control voltage outputs
• Four random gate outputs
• Raw signal output
• Conductive Leaf plate
• Semitone, random, harmonic overtone, and clocked modes
• Includes TENS sensor cable pads and TENS sensor cable clips

4
Installation
1. Confirm that the Eurorack synthesizer system is powered off.
2. Locate 14 HP of space in your Eurorack synthesizer case.
3. Connect the 10 pin side of the IDC power cable to the 2x5 pin
header on the back of the module, confirming that the red stripe on
the power cable is connected to -12V.
4. Connect the 16 pin side of the IDC power cable to the 2x8 pin
header on your Eurorack power supply, confirming that the red
stripe on the power cable is connected to -12V.
5. Mount the Instruō SCÍON in your Eurorack synthesizer case.
6. Power your Eurorack synthesizer system on.
Note:
This module has reverse polarity protection.
Inverted installation of the power cable will not damage the module.
Specifications
• Width: 14 HP
• Depth: 27mm
• +12V: 70mA
• -12V: 10mA

5
SCÍON | 'sö:ən |noun (biology) young shoot or stem useful for
sprouting or forming new roots, descendant of a noble family
Key
1. Leaf
2. Sensor Input
3. Sensitivity CV Input
4. Sensitivity
5. Density Fader
6. Density CV Input
7. Raw Signal Output
8. Tree
9. Channel 1 to 4 CV Outputs
10. Channel 1 to 4 Gate Outputs
11 . Channel 1 to 4 Slew
12. Channel 1 to 4 Attenuators
13. Channel 1 to 4 Gate Inputs
14. Channel 1 to 4 Hold Buttons
5
6
4
7
8
9 99 9
11
12 12
11
11 11
10 10 10 10
13
14 14 14 14
13 13 13
23
1
12 12

6
Stimulation
Leaf: The Leaf is a conductive electrode plate on the front panel
that is connected to the Internal Biofeedback Sensor.
Sensor Input: Signals present at the Sensor Input will connect to
the Internal Biofeedback Sensor.
• Biofeedback sources such as plants or human skin generate the
information converted to control voltages and gate signals. These
can be thought of as Seeds.
Seeds can be planted in multiple ways:
1. Touching the Leaf
When the Leaf is touched by a fingertip, the two conductive electrode
plates complete a circuit that affects the Internal Biofeedback Sensor.
CONDUCTIVE
ELECTRODE
BIOSENSOR

7
2. Connecting the source via TENS Sensor Cables
• Connect the 3.5mm TS end of the TENS Sensor Cable to the
Sensor Input.
• Connect the two sensor pads (or sensor clips) of the TENS Sensor
Cable to two separate areas of the organic source.
• Factors such as moisture, sunlight, and contact surface area can
determine the responsiveness of a plant.
• Every plant will have a different level of responsiveness.
3. Touching the end of a standard patch cable
• Connect a 3.5mm TS patch cable to the Sensor Input.
• When both the Tip and Sleeve of the patch cable are touched by a
fingertip, a circuit is completed that affects the Internal
Biofeedback Sensor.
4. Connecting any audio or control voltage signal
• Rising edge signals work best.
• White noise will continually excite the SCÍON.

8
Sensitivity
The Sensitivity parameter sets the responsiveness of the Sensor Input.
• Turning the knob anticlockwise decreases the responsiveness of the
Sensor Input and/or the Leaf.
• Turning the knob clockwise increases the responsiveness of the
Sensor Input and/or the Leaf.
• It is possible to find a threshold in which direct contact with the
biofeedback source is needed for biofeedback activity.
Sensitivity CV Input: The Sensitivity CV Input is a unipolar positive
control voltage input for the Sensitivity Input.
• Control voltage is summed with the knob position.
• Input Range: 0V - 5V.
Sensitivity Jumper: The Sensitivity Input and the Leaf are connected in
parallel when the Sensitivity Jumper is installed.
• This allows for simultaneous control of the Internal Biofeedback
Sensor via the Sensitivity Input and the Leaf.
• If the jumper is uninstalled, either the Sensitivity Input or the Leaf
can be used, but not both. Using the Sensitivity Input will disable the
Leaf in this configuration.
SENSITIVITY JUMPER
BACK

9
Density
The Density fader globally defines the distribution of available voltages
for each channel.
• Moving the fader downward will decrease the available control
voltage density.
• Moving the fader upward will increase the available control
voltage density.
• It is important to note that individual control voltage ranges can be
set via the Attenuators.
• The Attenuators affect the control voltage range set by the Density
parameter on a per channel basis.
• There is more information on the Density parameter in the Modes
section of the manual.
Density CV Input: The Density CV Input is a unipolar positive control
voltage input for Density.
• Control voltage is summed with the fader position.
• Input Range: 0V - 5V.
Raw Signal Output
The Raw Signal Output accesses a pulse waveform from the analogue
circuit used to generate the data at the Internal Biofeedback Sensor.
• This signal can be used as audio or control voltage/clock.
• Pressure applied to the Leaf will result in higher frequencies.
• Output range: 0V - 5V.

10
Channels
Tree: The Tree gives visual feedback of the Internal Biofeedback Sensor
and the signals present at each CV Output. With the bloom of each
colour, a new control voltage and gate duration is generated at the
corresponding outputs. .
CV Output: The CV Outputs generate control voltages based on the
activity of the Internal Biofeedback Sensor.
• Each CV Output corresponds to a different colour of the Tree.
• If the top of the Tree illuminates red, additional coin toss logic
determines the possibility of a higher rate of control voltage activity.
This red illumination can be thought of as a High Activity Indicator.
• From left to right, the CV Outputs correspond to the Blue, Green,
Yellow, and Orange illumination of the Tree from bottom to top.
• Output range: 0V - 5V.
Gate Output: The Gate Outputs generate gate signals with
random durations.
• Each Gate Output corresponds to a different colour of the Tree.
• From left to right, the Gate Outputs correspond to the Blue, Green,
Yellow, and Orange illumination of the Tree from bottom to top.
• If the top of the Tree illuminates red, additional coin toss logic
determines the possibility of shorter gate durations. This red
illumination can be thought of as a High Activity Indicator.
• Duration ranges: 100ms - 3.5s.
• Output voltage: 5V.
Slew: The Slew knobs set the amount of time it takes for the control voltage
signal to reach its final voltage level.
• This is also known as Portamento, Slide, or Glide.
• The Slew knobs individually affect the corresponding control voltage
outputs on a per channel basis.

11
• Turning the knob anticlockwise decreases the amount of slew
applied to the control voltage. If the knob is fully anticlockwise,
control voltage will be stepped.
• Turning the knob clockwise increases the amount of slew applied to
the control voltage.
Attenuator: The Attenuators individually scale the corresponding
control voltages on a per channel basis.
Gate Input: A signal present at the Gate Inputs will activate either
ratcheting for the corresponding Gate Outputs, in which the random
duty cycle of the gate signal is divided into either 4, 8, or 16
subdivisions, or force a change in voltage, acting like a more traditional
clocked sample and hold. The behavior of the Gate Inputs is determined
by the state of Mode 4: Clocked Mode.
Hold Button: The Hold Buttons freeze the current control voltage and
gate state of the corresponding channel.
• When control voltage is held, manually turning the Attenuators will
still scale the range of the CV Outputs.

12
Modes
To enter the Mode Menu, press all Hold Buttons down simultaneously
until the Hold Button corresponding to the currently selected Mode starts
to blink. Modes can then be selected by the Hold Buttons. Pressing
the corresponding Hold Button for Modes 1, 2, and 3 once will select
the mode. A Hold Button will blink when the corresponding mode is
selected. Pressing it again will exit the Mode Menu.
Once in the Mode Menu, Pressing the fourth Hold Button will toggle
Mode 4 on and off. Mode 4 is a secondary option and can be used in
conjunction with the three primary modes. Once it has been toggled,
pressing the Hold Button for the selected primary mode will exit the
Mode Menu.
Mode 1 - Quantised Mode:
With the Attenuators fully clockwise, the 0V - 5V output range of the CV
Outputs will be quantised to semitones.
• The Density parameter determines the range of available voltages.
• When the Density fader is fully downwards, the range of the control
voltage is limited to perfect octaves over a 0V - 5V range. Moving
the fader upwards will add voltages following the circle of 4ths until
all 12 chromatic voltages are available.
• The fader’s LED will blink to indicate a change in available voltages.

13
Mode 2 - Random Mode:
• With the Attenuators fully clockwise, the 0V - 5V output range of the
CV Outputs will be quantised in the same way as Mode 1, but with
an additional random voltage offset which is applied to the control
voltage signal.
• The Density parameter determines the range of available voltages.
When the Density fader is fully downwards, the range of the control
voltage is limited to dissonant octaves over a 0V - 5V range.
Moving the fader upwards will increase the number of available
voltage steps in a similar manner to Mode 1, but with addition
microtonal offsets applied.
• With the Density fader at its highest position, the CV Outputs will
generate random un-quantised voltage with a 0V - 5V range.
• The fader’s LED will blink to indicate a change in available voltages.

14
Mode 3 - Harmonic Overtone Mode:
• With the Attenuators fully clockwise, the 0V - 5V range of the CV
Outputs will be quantised to the intervals that outline the harmonic
overtone series.
• When the Density fader is fully downwards, the control voltages
are limited to the first harmonic. Moving the fader upwards will add
voltages following the harmonic overtone series up to the
12th harmonic.
• The fader’s LED will blink to indicate a change in available voltages.
• This mode changes the function of the Density CV Input to a voltage
follower that defines the fundamental of the harmonic overtone
series. With it, SCÍON can generate harmonics (voltages) related to
an external sequence or control voltage.

15
Mode 4 - Clocked Mode:
• This mode changes the function of the Gate Inputs to behave similar
to a classic sample and hold.
• With every gate or trigger signal present at the corresponding
channel’s Gate Input, a new random voltage is forced at the
corresponding channel’s CV Output. New voltages will only occur
if there is enough activity at the Internal Biofeedback Sensor.

16
Patch Examples
East Coast Counterpoint:
Output

17
Summary: When a biofeedback source is present, the CV Outputs send
voltages to the oscillators while the Gate Outputs trigger the envelope
generators. The CV outputs of the envelope generators open the filters
and VCAs, allowing the oscillator signals to pass through.
Biofeedback Path:
• Patch an input source (Plant, Audio, etc) into the Sensitivity Input
of the SCÍON.
Audio Path:
• Connect the desired waveform outputs of four separate oscillators to
four separate filter audio inputs.
• Connect all audio outputs of the filters to the audio inputs of four
separate VCAs.
• Connect all audio outputs of the VCAs to four inputs of a mixer.
• Monitor the output of the mixer.
• Tune all oscillators to unison (some detuning is allowed).
• Set the cutoff frequencies of the filters to desired positions.
• Set the resonances of the filters to desired positions.
• Set the individual levels of the VCAs to desired positions.
• Set the individual levels of the mixer to desired positions.
Control Path:
• Connect all CV Outputs to the 1V/Oct inputs of all four oscillators
(Each CV Output can be run through a separate quantiser for
tonal counterpoint).
• Connect all Gate Outputs to four separate envelope generator
trigger inputs.
• Connect all CV outputs of the four envelope generators to four
separate multiples.
• Connect one copy of the first envelope generator CV signal to the
cutoff frequency CV input of filter 1 and set the corresponding CV
attenuator to a desired position.

18
• Connect a second copy of the first envelope generator CV signal to
the CV input of VCA 1 and set the corresponding CV attenuator to a
desired position.
• Set the stages of envelope 1 to desired positions.
• Repeat the last four steps for the remaining channels of audio.

19
Biofeedback Audio:
Summary: When a biofeedback source is present, the CV Output will
open the filter while the Gate Output triggers the envelope generators.
The CV outputs of the envelope generators open the VCA, allowing the
Raw signal to pass through.
Biofeedback Path:
• An input source is required at the Sensitivity Input or the Leaf.
Audio Path:
• Connect the Raw Signal Output to the audio input of a filter
• Connect the audio output of the filter to the audio input of a VCA.
• Monitor the output of the VCA.
• Set the cutoff frequency of the filters to a desired position.
• Set the resonance of the filter to a desired position.
• Set the level of the VCA to a desired position.
Input Source
Gate Signal
Output

20
Control Path:
• Connect a desired CV Output to the cutoff frequency CV input of
the filter and set the corresponding CV attenuator to a
desired position.
• Connect a desired Gate Output to the trigger input of an
envelope generator.
• Connect the CV output of the envelope generator to the CV input of
the VCA and set the corresponding CV attenuator to a
desired position.
• Set the envelope stages to desired positions.