Erica Synths GraphicVco User manual

USER
MANUAL

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FEATURES
> Versatile waveform design
> Morphing between two selected waves
> Wavetable design
> Wavetable matrix design
> Versatile waveform alteration – FM, phase
distortion, ring modulation, wavefold,
wavewrap, bitcrush
> Configurable suboscillator output
> Skiff-friendly design
SPECIFICATIONS
> Audio output amplitude 10Vptp
> Octave range C0 – C8
> Sample rate 96kHz
> Wave resolution 1024 points
> Unipolar CV input range 0 - +10V
> Bipolar CV input range -10V - +10V
> Panel width 16HP
> Module depth 30mm
> Power consumption 152mA@+12V,
20mA@-12V
The Graphic VCO allows you to draw your own
waveforms, arrange them in wavetables and
wavetable banks, morph between two selected
waves and alter the resulting wave in advanced
ways (FXes) – apply FM, phase distortion, ring
modulation, wavefold/wavewrap, bitcrush.
Waves, wavetables, FXes and other settings
can be saved and recalled from the memory
instantly. The module has two outputs – the
main output and the output with configurable
suboscillator.
THANK YOU FOR PURCHASING
ERICA SYNTHS GRAPHIC VCO! WE
BELIEVE, THIS WILL BE ONE OF
YOUR FAVOURITE MODULES IN YOUR
EURORACK SYSTEM.

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THE LCD gives visual feedback on the main functions of the
module.
THE LEFT ENCODER allows to access main functions
in the menus.
THE RIGHT ENCODER allows to access secondary functions
in the menus.
BACK button allows to return to the menu above
ADJUST MASTER TUNE of the VCO. Tune range is 16Hz - 4kHz,
larger range can be achieved with CV applied to 1V/oct input. For
FINE TUNE push and hold the right encoder, and rotate the left
one to adjust the tune between +-50 cents. The Fine Tune function
works in the main screen and the oscilloscope screen only!
ADJUST FX (depending on selected function) amount manually.
If FX AMT CV is patched, this knob becomes FX amount CV
attenuator.
THIS IS 1V/OCT INPUT It accepts CVs from 0V to +8V for 8 octave
tuning
THIS IS FX AMOUNT CV INPUT.
It’s unipolar and accepts 0 – +10V CVs
THIS IS FX PARAMETER CV INPUT. It’s bipolar and accepts
-10V - +10V CVs. In the Wavetable Matrix mode this CV input selects
waves in horizontal direction
THIS IS MORPH CV INPUT. It’s bipolar and accepts
-10V - +10V CVs. In the Wavetable Matrix mode this CV input selects
waves in vertical direction
THIS IS THE MAIN OUTPUT OF THE MODULE
THIS IS THE CONFIGURABLE SUBOSCILLATOR/MIX OUTPUT
DEPENDING ON FX selected, this knob ADJUSTS THE FX
PARAMETER, for example, FM frequency, if FM is selected. If FX
CV is patched, this knob becomes FX CV attenuator. In Wavetable
Matrix mode use this knob to morph thru waves in horizontal
direction.
THIS KNOB allows you to MORPH between wave A and wave B
manually. If MORPH CV is patched, this knob becomes MORPH CV
attenuator. In Wavetable Matrix mode use this knob to morph thru
waves in vertical direction.

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> WAVE DESIGN MENU <
The BASIC MODE is WAVE DESIGN
and Morphing between waves A and
B. In this mode you can use encoders
to draw two waves – A and B (or
select ones from the list) and morph
between them manually or via Morph
CV, thus getting interesting in-between
waveforms. Futuremore, you can alter
the wave by applying FXes - frequency modulation, phase distortion, ring
modulation, bitchrush, etc.
Note that FXes are master settings, and they alter the signal before the
output.
Use the left encoder to navigate to A/B and push the encoder to enter the
wave design mode.
In Wave design mode you can select A
and B waves from the list OR DESIGN
NEW WAVEFORMS. The easiest way
is to load some waveforms from the
lists and morph between them.
To do so, click the left encoder on the
LOAD icon to load the waveforms in
the left window and click the right
encoder to load waveforms in the
right window.
Use the left and the right encoders
to navigate thru the list of A and B
wavetables correspondingly and click to confirm selection then repeat
the same to chose the waves form the list within the wavetable. Once
waveforms are loaded, you can choose to edit them. Editing waveforms
is similar to drawing a new waveform as described below.
> THE MAIN MENU <
> MODE SELECT MENU <
This is the MAIN WAVE
DESIGN menu. It will
change depending on the
mode selected
This is MODE SELECT menu.
Selected mode appears as a
text below the icons
This is OSCILLOSCOPE and
PLAYBACK MONITORING
menu
This is SNAPSHOTS LIST
menu
This is FX MANAGEMENT
menu
This is WAVE and WAVETABLE
LIST and MANAGEMENT
menu
This is SUBOSCILLATOR
CONFIGURATION menu
This is THE MODULE
SETUP/CONFIGURATION menu
Let’s start with SELECTING
OPERATING (playback) M O D E !
Use the left encoder to navigate
thru screen and push the encoder to
confirm the selection.
The Graphic VCO has FOUR MAIN
MODES:
1. Morphing between waves A and B
2. Wavetable
3. Wavetable Bank Matrix
4. Drum synthesis mode
Use the left encoder to navigate thru mode icons and push the
encoder to confirm the selection.

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Now you can rotate the left encoder
to move same marker selection left
or right or click the right encoder and
change the width of the selection.
You can click the left encoder to access
the top menu and select different
principal waveform (pulse wave is
selected in the example on the left). Repeat steps above until you are
happy with your unique waveform. You can save it to the waveform list –
see instructions below!
Once you have clear screen, you can
draw one period of the wave and
simultaneously listen to the result. To
do so, use the left encoder to select
the principal waveform, you wish to
start with, from the icons above and
click to confirm selection. Available
principal waveforms are pulse, triangle, sine, ramp, sawtooth and
logarithmic sine. Example shows sine waveform selected.
Once the waveform is selected, you
can start designing a wave. There’s
a marker on the beginning of the
horizontal axis.
Rotate the left encoder to move the
marker right or left. Push promptly
and rotate the right encoder to split
the marker and define width of the selection. Now you have two options:
1) Rotate the left encoder to move selection right or left,
2) Click the right encoder and rotate it CW to draw the positive cycle of
the sinewave or CCW to draw the negative cycle of the sinewave.
In the wave edit mode you’ll see the
waveform and by PUSHING THE LEFT
encoder, you’ll access the wave edit
menu on the top of the screen. Rotate
the left encoder to access wave edit
options! Editing waveforms is similar
to designing the new one – please,
refer to procedure below. Particularly interesting is wave editing via
managing amplitudes of harmonics.
If you wish to save the waveform after editing choose the far right icon
and click the encoder to confirm.
The name screen will appear and
you can name the waveform. It will
be saved as the last in the waveform
list. See the Waveform and wavetable
management procedures below.
To DRAW A NEW WAVEFORM,
load any waveform, select edit mode,
delete the wave and start design from
scratch. Or select NEW in the MANAGE
menu.
Once waveforms are loaded, you can
just PLAY THEM BACK or EDIT
them. Rotate left or right encoder to
select edit icon and click to advance
to wave edit mode.

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The wave with the corresponding
spectrum of harmonics will appear
on the screen. You also can alter
the wave by adjusting harmonics.
Use the left encoder to navigate thru
harmonics (selected one gets bolder)
and the right one to adjust amplitude
of the harmonic.
You also can design the wave only by adding harmonics in various
amplitudes. Just select the new wave and start with the SPECTRAL icon.
Each harmonic represents a sinewave with a frequency which is multiple
of the first harmonic. Use the left encoder to navigate thru harmonics
(selected one gets bolder) and the right one to adjust amplitude of the
harmonic.
If you are not happy with the wave
created, just click the X BOX and the
wave will be erased and you can start
drawing the new wave from scratch.
Once you are happy with the wave,
you’ve created, select SAVE box and
save the wave. NAME menu will
appear.
In the NAME menu you can name your
waveform and save in user generated
wavetables. Follow the pop-up
screens to allocate the wave in a
desired wavetable. You can change
the position of the wave in the list in
the MANAGE menu.
As you draw the wave, you can check
the HARMONIC CONTENT of it,
specifically, the first 32 harmonics. To
do so, use the left encoder to select
SPECTRAL icon in the top row.
You can’t move the cursor left, as the
wave should change over the time,
and it can’t go back in the past. We
recommend to draw waves that start
and end at horizontal axis otherwise
you may hear undesired clicks.
In LINE SKETCH mode you can
draw the wave by connecting lines
between two points defined by
cursor. move the cursor to desired
position and push the left encoder to
initiate drawing.
In the PEN SKETCH mode you just
use both encoders to draw the wave
form scratch. The left encoder moves
drawing cursor up and down, the
right – right. Push the right encoder to
initiate drawing. The cursor will change
to small cross.

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X and Y under the oscilloscope
screen represent currently selected
wave position, while OFS - allows
you to offset all wavetables in the
screen up. For example, if you have
32 wavetables in total then OFS: 2/16
will mean that the screen indicates
wavetables from 3 to 18. You can
change the offset position by clicking and rotating the right encoder.
The default setting of the wavetable matrix is 8 wavetables x 8 waves. Use
the left encoder to move the matrix left or right and the right encoder to
move the matrix up and down.
Use X and Y potentiometers or relevant CV inputs (X and Y) to navigate
through waves within the matrix.
> WAVETABLE MATRIX MENU <
In Wavetable Matrix mode you have
your wavetables and waves displayed
as a matrix, where rows represent
wavetables (wavetables appear in the
order as set in MANAGE menu) and
columns – individual waves. All waves
are represented as dots in the matrix
and active wave – one which is played back – as bolder dot.
You can alter the size of the matrix by
clicking the left encoder. At the first
click the bold dot in the top left corner
will appear and you can adjust the
size of the matrix by rotating left and
right encoders, at the second click the
bold dot will appear in the bottom
right corner and you can do adjustments again. The third click will freeze
the size of the matrix and you can use left and right encoders to move
the matrix vertically and horizontally.
Note that CV inputs automatically adjust to the size of the matrix,
meaning, CV span of -5V to +5V will play back all waves in the matrix and
will not play back ones outside.
> WAVETABLE MENU <
In WAVETEBLE MENU you can
select wavetables of 16 waves from
the list of BANKS and play them back,
while morphing thru waves using
MORPH knob or Morph CV.
Use the left encoder to navigate
thru the list of BANKS and push it to
confirm selection.
As the bank is selected, you can use
MORPH knob to browse through the
waves in the bank and hear, how the
bank sounds.
You can design wavetables in Wave
list menu or in the Graphic VCO
Google App (see below). Waves added
to the wavetables are automatically
morphed for the best sound.

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> DRUM MODE <
In DRUM MODE you can use
the Graphic VCO as a percussion
synthesizer, where the percussion
sounds are built based on wavetables
present in the Graphic VCO. FXes can
be applied on top of the percussion
sounds. IN ORDER TO USE THE
GRAPHIC VCO AS A PERCUSSION
MODULE, PATCH THE TRIGGER
SIGNAL IN THE FX AMT INPUT!
The Graphic VCO in the Drum mode has
built in amplitude and pitch envelope
with adjustable Decay time, as well
as pitch envelope shape adjustment
and pitch envelope depth. Use the left
encoder to navigate between settings
(wavetable select, amplitude decay,
pitch decay, pitch envelope shape
and pitch envelope depth) and the
right one to adjust the setting. All
potentiometers have same functions
as in other modes.
You can save percussion sounds with all
settings as a Snapshot (see page 21).
In FX menu you can apply several
effects on the waves being played
back. FXes are master settings and
they are applied on the resulting
wave before the output. FXes (except
frequency modulation) ar NOT applied
to the suboscillator.
Rotate the left encoder to scroll thru effects. Selected effect appears in
the top left corner of the screen. Available effects (in order of appearance)
are Frequency Modulation, Ringmodulator, Phase Distortion, Wavefolder,
Wavewrapper, Bitchrush/Sample rate reduction and Overdrive.
FX AMOUNT potentiometer defines the depth of the effect (for some
effects – Dry/Wet); FX potentiometer sets the frequency of the internal
modulation oscillator (see below). When external CVs are applied, these
potentiometers become attenuators. Please note that FX AMOUNT CV
input accepts positive only CVs.
Let’s explore the FM EFFECT!
Push the left encoder to access the
DEPTH setting – relative maximum
value (depth) for which the frequency
modulation will be performed, in
other words – the depth of the
frequency modulation when FX
AMOUNT potentiometer is in full CW position. Available values are form
0 to 100%. Push the left encoder again to return to effect select menu.
“Oscilloscopes” – the main signal an the modulator are just for visual
reference – they do not perform actual measurements.
On the right side of the screen you
have modulator settings. There are
three options: POT (potentiometer),
external modulation input (IN) and
the internal modulation oscillator
(OSC). Rotate the right encoder to
select one of those! Push the encoder
to access the next modulator setting!
> FX MENU <

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With SYNC: OFF you can adjust the
internal oscillator frequency. Rotate
the FX potentiometer to set the
frequency from 0.13Hz to 4000Hz.
Let’s start with the INTERNAL
MODULATION OSCILLATOR (OSC).
First, you have selection of the
waveforms (WAVE). Rotate the right
encoder to browse the waveforms.
Available waveforms are: Sine,
Triangle, Ramp, Sawtooth, Square,
Sample&Hold. Note that not all modulation waveforms will give nice
resulting sound. We recommend to begin experiments with the sinewave.
Once you have selected the waveform push the right encoder to configure
synchronization of the modulation oscillator. Rotate the right encoder to
select synchronization ON or OFF, meaning, if the internal oscillator runs
independently or its’ frequency is synchronized to the frequency of the
main oscillator.
With SYNC: ON you can select
synchronization ratio. Rotate the FX
potentiometer to desired sync ratio
(the module provides both multiplied
and divided frequencies). Note that
module will play back the resulting
wave in real time and you can hear
modulation sweetspots.
IF THE EXTERNAL MODULATOR
IS SELECTED (IN), you can apply
the modulation CV (LFO, envelope
generator or any other modulation
source) to the FX CV input, and
adjust its amplitude with the FX CV
potentiometer.
The small “oscilloscope” will show you the waveform of the incoming CV.
Push the right encoder to access oscilloscope settings:
SCALE adjusts the timing to fit the incoming modulation wave in the
oscilloscope horizontally;
GAIN – sets the gain of the FX CV input;
BIAS – offsets the incoming CV on the FX CV input.
PHASE DISTORTION has similar
controls, and the setting POT turns
FX potentiometer in manual phase
distortion control.
For some effects (specifically, phase
distortion, wavefold, wave wrap,
bitcrush) MANUAL CONTROL (POT)
over the effect gives nice results. Just
use the FX potentiometer to alter the
waveshape.
RINGMODULATOR works similar
to the FM. The principal oscillator
is considered a main signal, but
Modulation oscillator or signal applied
to the FX CV – a carrier.
Modulation controls are basically
identical.

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FOLD AND WRAP FX provides you
distinct wavefolder or wavewrapper.
Rotate the right encoder to select
between wavefolder (FOLD) or
wavewrapper (WRAP). Push the right
encoder to access GAIN adjustment
and OFFSET adjustment if you use an
external modulation source.
Use modulation setting POT for manual wavefolding with the FX
potentiometer.
CRUSH FX is bitcrusher. Use
modulation setting POT for manual
bit rate reduction with the FX
potentiometer.
DRIVE FX is overdrive. Use
modulation setting POT for for
controlling overdrive level with the FX
potentiometer.
In Suboscillator configuration menu
you can altrer suboscillator settings.
The suboscillator is assigned to
the OUT2. No FX (except frequency
modulation) is applied on the
suboscillator.
Rotate the left encoder to select
settings you wish to alter and rotate
the right one to alter the setting. Click
the encoder to confirm.
By OFFSET you define the
suboscillator frequency against the
principal oscillator. You can offset it
by semitones and maximum offset is 24 semitones (-2 octaves)
You can DETUNE the suboscillator by +-50 cents for analogue-like
pulsating sound.
MIX% IS DRY/WET FADER for the OUT2, where 0% suboscillator only
and 100% is copy of the signal form OUT1. All other positions give a mix
of principal oscillator and suboscillator.
WAVE allows you to select, what wave is assigned to the suboscillator.
Click and rotate the encoder to select the wave.
> SUBOSCILLATOR CONFIGURATION MENU <

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The OSCILLOSCOPE MENU is
designed to monitor signal status
during performance.
It shows a waveform being played
back at the moment including mor-
phing between waves and FXes
applied.
> OSCILLOSCOPE MENU <
Push the left encoder to access con-
trols status menu – it shows the po-
sition of controls and inputs used for
the specific snapshot. In example on
the left you can see the settings of
the potentiometers and CV shapes
applied to CV inputs.
It also indicates the tune of the VCO in
notes and Hz, as well as time passed
from the powering on the modular
system. If you wish to reset the timer
to keep timing of your performance,
just push the right encoder and the
timer will reset to O.
To delete or rename the snapshot,
push and hold the left encoder for
1” and delete/rename screen will
appear.
Once you are happy how your designed
waves or wavetables with suboscillator
configuration and FXes applied
sound you can save a SNAPSHOT – a
combination of all your settings for a
specific sound, which can be instantly
recalled during the performance.
To save the snapshot PUSH AND HOLD THE BACK BUTTON FOR 2”
and the snapshot will be automatically saved.
As the snapshot is saved, the
snapshot name menu will appear.
Use the right encoder to navigate
thru characters and click to confirm
the selection. Click OK to confirm the
name.
Confirm delete or rename by pushing
the left encored.
To recall the snapshot, open the
snapshots menu and us the left
encoder to select the snapshot form
the list. Click the encoder to confirm
the selection.
NB! When the new snapshot is
selected potentiometers (except
TUNE) will start to have effect only when they are rotated to the position
saved with the snapshot (see the Oscilloscope menu).
> SNAPSHOTS MENU <

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> MANAGE <
MANAGE MENU allows you to
rearrange wavetables, edit them and
create new ones.
Rotate the left encoder to browse
through the wavetables and rotate
the right encoder to browse through
the waves within the wavetable.
Pushe the left encoder for 1” to access
the wavetable edit/rename/delete
menu.
NB! Factory preset wavetables can not
be overwritten. You can edit them,
but you will need to save them under
different name.
In the DEVICE CONFIGURATION
MENU you can adjust system and
hardware settings.
Rotate the left encoder to access
various configuration settings
Info menu contains information on
firmware version and memory usage
In the display configuration menu you
can adjust display brightness, contrast
and invert the display appearance to
the black background. Use the left
encoder to browse thru menu and
rotate it to adjust settings. If you
wish to film a demo of the module,
we recommend to set minimum
brightness ;)
In the playback (oscilloscope)
configuration menu you can select,
how waves within the wavetabes are
played back. Rotate the right encoder
to select between smooth (morphed) or
discrete transition between waves.
> DEVICE CONFIGURATION MENU <

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6) Release the encoders and the
firmware update screen – Erica Synths
BOOTLOADER will appear on the
module.
7) Hit the PROGRAMM button in the
Updater App screen!
8) The module will indicate the
update status and will notify when
the update is completed
All waveforms and snapshots saved
on the module will not be affected
after the firmware update.
To have the module functionality
up to date, we recommend you
time by time check announcements
about firmware updates for the
Graphic VCO on www.ericasynths.
lv or on our social media.
You can update the firmware of the
module via miniUSB cable.
To do so, follow instructions
below:
1) Remove the module from the rack and disconnect the PSU cable
2) Open Google Chrome and open Erica Synths Firmware Updater App.
3) Connect the module to the USB port of the PC
4) Select a Graphic VCO module form the list
5) Push and hold both encoders and connect the module to the PSU
> FIRMWARE UPDATE <
In the IN/OUT CONFIGURATION
MENU you can configure CV inputs
by adjusting their gain, and bias. Use
the left encoder to select the input
or setting and right one to adjust the
amount of the setting.
In the CALIBRATION MENU you
can calibrate the Graphic VCO to your
MIDI-CV converter or the sequencer.
For calibration you will need precision
voltage sources - 1,000V and 5,000V,
for example MIDI-CV converter. Patch
the output of the MIDI-CV converter
to the 1V/Oct input of the Graphic VCO
and play C1 on the keyboard (it should
generate 1V on the CV output) and
then push the right encoder (1.000V
will appear on bottom of the screen).
Then play C5 on the keyboard (it
should generate 5V on the CV output)
and push the right encoder again
(5.000V will appear on the bottom of
the screen. Calibration complete!
In QUANTIZER MENU you can select
one of 9 preset quantization scales.
Simply rotate the left menu to set the
scale.
In MEMORY CLEAR MENU you can
delete all user generated wavetables
and snapshots. Rotate the left
encoder to select the Wavetables or
Snapshots and push it to confirm. No/
Yes pop-up will appear to confirm the
selection. You can not delete factory
preset wavetables.

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This device complies to the EU guidelines and is
manufactured RoHS conforming without use of lead,
mercury, cadmium and chrome. Nevertheless, this device
is special waste and disposal in household waste is not
recommended.
You will find Erica Synths terms of warranty at
www.ericasynths.lv.
Items for return, exchange and/or warranty repair
have to be sent to:
Erica Synths, Andrejostas Str. 43, Riga, Latvia, LV-1045
User manual by Girts Ozolins@Erica Synths.
Design by Inese Verina-Lubina and Anna Matisone.
Copying, distribution or any commercial use in any way is
prohibited and needs the written permission
by Erica Synths.
Specifications are subject to change without notice.
In case of any questions, feel free to contact us through
www.ericasynths.lv or via e-mail [e-mail].
> DISPOSAL <
> CREDENTIALS <
> SAFETY INSTRUCTIONS <
Please follow the instructions for use of the Erica Synths
Graphic VCO below, ‘cause only this will guarantee proper
operation of the module and ensure warranty from Erica
Synths.
Water is lethal for most of the electric devices,
unless they are made waterproof. Erica Synths
module is NOT intended for use in a humid or
wet environment. No liquids or other conducting
substances must get into the module. Should
this happen, the module should be disconnected
from mains power immediately, dried, examined
and cleaned by a qualified technician.
Do not expose the module to temperatures above
+50° C or below -20° C.
Transport the instrument carefully, never let it
drop or fall over. Warranty does not apply to
modules with visual damages.
The module has to be shipped in the original
packaging only. Any module shipped to us for
return, exchange and/or warranty repair has to
be in its original packaging. All other deliveries
will be rejected and returned to you. Make sure
you keep the original packaging and technical
documentation.