SYNTHR SYNTHR3 User manual

The SYNTHR3
Modern semi-modular synthesizer with three-
way paraphony, duophony, MIDI control,
arpeggiator, integrated sequencer, and
modulation matrix storage.

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SYNTHR3 Manuel V1.01 EN
User Manual

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SYNTHR3 Manuel V1.01 EN
TABLE OF CONTENTS
WELCOME ________________________________________________________________________4
CONNECTIONS _____________________________________________________________________5
WARNING_________________________________________________________________________5
INTRODUCTION ____________________________________________________________________5
FIRST VISIT .....................................................................................................................................................................6
MORE DETAILS _____________________________________________________________________7
THE SOURCES ................................................................................................................................................................7
MIXER ............................................................................................................................................................................8
FILTERS ..........................................................................................................................................................................8
MODULATIONS............................................................................................................................................................10
OUTPUTS ________________________________________________________________________12
THE PLAY MODES __________________________________________________________________13
MONOPHONIC Mode filter in parallel.........................................................................................................................13
MONOPHONIC Mode serial filter ................................................................................................................................14
DUOPHONIC Mode......................................................................................................................................................15
PARAPHONIC 1 Mode..................................................................................................................................................16
PARAPHONIC 2 Mode..................................................................................................................................................17
ARPEGIATOR Mode .....................................................................................................................................................18
STEP SEQUENCER Mode ..............................................................................................................................................18
CONTROLLER MIDI USAGES __________________________________________________________18
MIDI CONTROLLER FUNCTIONS...................................................................................................................................19
POWER UP ...................................................................................................................................................................19
Operating Mode ..........................................................................................................................................................20
OTHERSfUnctions ........................................................................................................................................................27
APPENDIX ________________________________________________________________________29
APPENDIX 1 : SYNTHR3 DIAGRAM...............................................................................................................................30
APPENDIX 2 : MIDI KEYBOARD ....................................................................................................................................31
APPENDIX 3 : arpègGIO MODES ..................................................................................................................................32
APPENDIX 4 : Presets...................................................................................................................................................33
APPENDIX 5 : MIDI CONTROLLER DIAGRAM ...............................................................................................................34
Annexe 6 : HOW TO CHANGE A FILTER .......................................................................................................................35
APPENDIX 7 : REAR FACE.............................................................................................................................................36
APPENDIX 8 : OUTSIDE CLEANING...............................................................................................................................36
PATCH TEMPLATE _________________________________________________________________37

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SYNTHR3 Manuel V1.01 EN
WELCOME
Thank you for purchasing the SYNTHR3, and thus supporting French electronic music making.
This project was born from the need of a musician to have something else and from my imagination. A brilliant developer
friend was quickly joined to this project, also participating in the diffusion of electronics for music. I would like to thank Jean-
Luc Lartigue (http://www.ozoe.fr) without whom this project would not have been possible.
I thank our master to all, Yves Usson who is always available to give his technical advice.
I would like to thank Laurent Cartaux for his precious help on the beautiful SYNTHR3 cabinet.
And I will finish my thanks for my wife who gave me complete freedom on long hours of development and tuning.
The very small company SynthR SAS was born from this project in order to support you as best as possible.
I strongly advise you to read this manual at least once if you don't want to have any surprises such as not hearing anything
coming out.
We wish you long hours of research and music for your greatest pleasure.
https:// www.synthr.fr
Rémy WASSELIN

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SYNTHR3 Manuel V1.01 EN
CONNECTIONS
Rear:
Channel 1, Channel 2 outputs: Jack 6.35 line level
CV1, CV2 outputs: 3.5mm jack -1V to +7V with master tune at 440Hz or -2V to +6V or 0V to 8V, impedance 1Kohm
Gate 1, Gate 2 outputs: Jack 3.5mm 0-5V impedance 1Kohm
Clock: Jack 3.5mm TTL compatible clock available in Arpeggiator and Sequencer mode, 0-5V, impedance 1Kohm
Mains socket: IEC - 240V AC 50Hz only, fitted with a 315mA fuse.
Front :
USB type B socket: 32-bit processor firmware update and MIDI software control
MIDI IN Din 5-pin: Keyboard or sequencer input.
MIDI THRU Din 5-pin: Repeat MIDI IN jack
MIDI Polychain Din 5-pin: Used to connect multiple SYNTHR3s to increase polyphony.
Dimensions: 625mm*485mm*225mm
Weight: 14 kg
Power consumption: 40 VA
WARNING
Although you can open the rear panel to change a filter or other module, it is forbidden to interfere with the power supply,
as the presence of electrical voltage may cause a risk of electric shock.
Use a standard power cord.
INTRODUCTION
The SYNTHR3 is an analog synthesizer with subtractive synthesis and MIDI controls.
Like any analog synthesizer whose VCOs are not digitally controlled, it is susceptible to frequency drift due to excessive
temperature and beats between VCOs are audible. An internal tuning fork allows you to check the VCOs' timing.
In a historical modular synthesizer, the patches are made by cables that connect the modules together. For the SYNTHR3, no
cables, but push buttons that connect the modules together. This makes the connections between modules more visible,
more legible. These push buttons are digital switches and can therefore be stored in profiles called "Patch".
The modular side is preserved by the use of memory patches and by the possibility of exchanging certain modules by the user
by opening the back panel. In particular, several filters are available.
Although pre-wired, the choice of modulations remains important.
The MIDI control is done through a MIDI to CV and Gate converter which receives a MIDI master keyboard.
In order to take advantage of the SYNTHR3's features, this keyboard must have: pitch bend, modulation wheel, aftertouch
and velocity as well as a sustain pedal.
The MIDI converter can also be controlled by a DAW software via the USB port.
The Arpeggiator part and the Sequencer part of the SYNTHR3 will be able to receive via the DIN socket a MIDI clock and the
associated "Sync 24" commands.

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SYNTHR3 Manuel V1.01 EN
FIRST VISIT
The SYNTHR3 consists from left to right of :
The oscillator section consists of 3 VCOs. VCOs 1 and 2 are identical except that VCO2 can synchronize with VCO1.
VCO3 does not have a PW modulation section, but has an additional waveform, it can synchronize to VCO1 as well
and above all can be transformed into an LFO (LFO1). This section is reinforced by a sub-oscillator of the VCO1
comprising 3 waveforms at octave -1 and one at octave -2.
A modulation section with a digital LFO (LFO2) comprising 16 modifiable waveforms. A Sample and Hold and a noise
generator.
An ensemble MIXER which allows to send each of the 6 available sources to the VCF1 or / and depending on the
playing modes, the VCF2.
The filter section with a low-pass VCF1 (LP) and a low-pass or multimode VCF2 *
Underneath are two envelope generators, one serving as modulation for the VCOs and LFO2, the other dedicated to
the filters.
At the bottom there is a general volume and a frequency tuning over more or less an octave.
Finally on the right are 2 VCAs with an envelope generator whose role will be specified according to the play mode.
A Ring Modulator between VCO1 and a mixer of VCO2 and VCO3.
switchable portamento for VCO1 and VCO2.
We went around the analog part and we arrive on the MIDI controller with its 4 lines screen that will allow us to control the
different playing modes, the MIDI channel if needed, the Tuning fork, to save "patches" and to activate the internal
Arpeggiator as well as the internal Sequencer. This MIDI controller has no action on the audio synthesis.

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SYNTHR3 Manuel V1.01 EN
MORE DETAILS
THE SOURCES
VCO1 :
Octave selector on + or - 2 octaves,
Fine tuning on + or - 5 semitones,
Keyboard monitoring via MIDI to CV including the pitch wheel of + or - 1 tone.
Pulse width adjustment (PW) 10 to 90%.
Frequency modulation by:
Adjustable input 1: Aftertouch (if the keyboard delivers it) or Modulation
Envelope or LFO2.
Adjustable input 2: LFO1 or Sample and Hold or VCO2 (Cross modulation).
Pulse Width Modulation (PWM):
Adjustable input 1: Aftertouch (if the keyboard delivers it) or Modulation
Envelope or LFO2.
Adjustable input 2: LFO1 or VCO2 (Cross modulation).
Simultaneous outputs: Triangle, Sawtooth, Pulse.
VCO2 :
Octave selector on + or - 2 octaves,
Fine tuning on + or - 5 semitones,
Keyboard monitoring via MIDI to CV including the pitch wheel of + or - 1 tone.
Synchronization on VCO1
Pulse width adjustment (PW) 10 to 90%.
Frequency modulation by:
Adjustable input 1: Aftertouch (if the keyboard delivers it) or Modulation
Envelope or LFO2.
Adjustable input 2: LFO1 or Sample and Hold or VCO2 (Cross modulation).
Pulse Width Modulation (PWM):
Adjustable input 1: Aftertouch (if the keyboard delivers it) or Modulation
Envelope or LFO2.
Adjustable input 2: LFO1 or VCO2 (Cross modulation).
Simultaneous outputs: Triangle, Sawtooth, Pulse.
VCO3 (Mode VCO)
Octave selector on + or - 2 octaves,
Fine tuning on + or - 5 semitones,
Keyboard monitoring via MIDI to CV including the pitch
wheel of + or - 1 tone.
Synchronization on VCO1 (cancel LFO mode)
Frequency modulation by ajustable input: Aftertouch or
modulation Envelope or LFO2.
Simultaneous outputs: Triangle, Sawtooth, Reverse
Sawtooth, Square

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SYNTHR3 Manuel V1.01 EN
SUB :
Output at octave -1 of the VCO1: Triangle, Sawtooth, Square.
Output at octave -2 of VCO1: Square
NOISE
White noise
Pink noise
Ring Modulator
Between permanent VCO1 and mix of VCO2 or /and VCO3.
MIXER
Each of the above sources can be sent on VCF1 and / or the VCF2 in MONO and
PARAPHONIC mode 1
For the other DUOPHONIC, ARPEGIATOR, SEQUENCER modes, VCO1 will be forced
on VCF1, VCO2 and VCO3 on VCF2. Free choice of SUB, RM and Noise.
For PARAPHONIC 2 mode the mixer only allows VCO1, SUB, RM and Noise to be
mixed to accompany the first not

CAUTION: If no signal is selected on VCO, SUB, RM, NOISE and no destination VCF1 or
VCF2 is selected, there will be no sound output.
FILTERS
VCF1 (LP)
Suggested choice *: ARP type 4072, MOOG (transistor ladder), AS3320 LP... all in 24dB per
octave.
Cutoff
Resonance
Keyboard tracking 0 to 120%. 100% is between 8 and 9 sign pot.
Dedicated Envelope Input
Adjustable modulation input 1: LFO1 or LFO2 or S&H.
Adjustable modulation input 2: Aftertouch or Modulation wheel

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SYNTHR3 Manuel V1.01 EN
VCF2 (Multimode ou LP)
Suggested choice *: ARP, MOOG, AS3320 LP, SEM, STEINER, AS3320 MM...Multimodes are 12
dB per octave.
Cutoff
Resonance
Keyboard tracking 0 to 120%. 100% is between 8 and 9 sign pot.
Dedicated Envelope Input
Adjustable modulation input 1: LFO1 or LFO2 or S&H.
Adjustable modulation input 2: Aftertouch or Modulation wheel
Low Pass, Band Pass, High Pass selection for multimodes only
It can be interesting to press LP and HP at the same time.
CAUTION: If no filter mode is selected there will be no sound on the audio output..
* Other types of filters may be offered.
* * In the VCF2 slot (slot 2) an LP filter can be plugged in, in which case the BP and HP modes will not be accessible.
* * * Note: The proposed filters are based on known schematics, but are by no means clones of the components. It is
therefore possible that some of them do not have the grain, the fineness, the harmonic range or even the known defects of
these famous filters.

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SYNTHR3 Manuel V1.01 EN
MODULATIONS
LFO1 (LFO Mode of VCO3)
LFO On: with frequency display in the knob. In this case the VCO3 no longer exists in the Mixer.
Range selector: 5 frequency ranges
-2 from 0,37 to 0,7 Hz
-1 from 0,74 to 1,4 Hz
0from 1,5 to 2,8 Hz
+1 from 3 to 5,5 Hz
+2 from 6 to 11 Hz
Frequency potentiometer corresponding to fine tuning
djustable frequency modulation input: Aftertouch or
Modulation Envelope or LFO2
Simultaneous outputs: Triangle, Sawtooth, Reverse Sawtooth, Square
Note:
Remember to re-tune the frequency to return to VCO mode..
LFO1 has several possible destinations. If the LFO1 button is not pressed it is in VCO mode and therefore in the audio range.
This can be used to do frequency modulation on the other VCOs as well as on the filters
LFO2 (Electricdruid ™)
Range selector: 4 frequency ranges
1from 0,05 to 12,5 Hz
2from 0,1 to 25 Hz
3from 0,2 to 50 Hz
4from 0,4 to 100 Hz
Frequency potentiometer
Waveform distortion potentiometer:
Examples :
* The position respecting the waveform is at noon or 50%
otherwise the waveform is distorted. In the case of the square
waveform, this potentiometer acts on the duty cycle (PW).
Sample & Hold sample rate potentiometer acting on any
waveform.
Waveform selector among 8 and 8 more by pressing "Alt".
LFO On button: without it no exit. The LED shows the frequency.
Knobs for triggering the LFO by the modulation envelope.
LFO trigger button by Aftertouch

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SYNTHR3 Manuel V1.01 EN
Note : MIDI keyboards with aftertouch have the possibility to have several curves. If your keyboard is set to a linear
curve by default, the SYNTHR3 will force this curve to become exponential in order to increase sensitivity.
Knob for triggering the LFO with the Modulation Wheel.
It may seem confusing on these last 3 buttons not to see the LED flashing. This one will start to blink when the
action will be carried out.
SAMPLE & HOLD
Adjustment of the internal sampling frequency, displayed on the knob, from 1 to 100
Hz.
By successively pressing the "LFO2" button, the sampling frequency will be that of
the S&H itself, that of LFO2 or none at all. The LED shows the frequency or is off as
the case may be.
Adjusting the level of the sampled signal:
White noise
LFO1 as alternative source to be sampled
ADSR Modulation
ADSR envelope generator for frequency or duty-cycle modulation of VCOs and
envelope generator for LFO2
Possibility of delay from 0 to 3 seconds in relation to the Keyboard Gate via
the Delay button.
The Velocity button allows you to set the Sustain value according to the
velocity provided by the MIDI keyboard.
The Retrigger button allows one play or each note press restarts the AD
cycle.
* We will see that this envelope can change roles depending on the Play Mode (see below)
ADSR Filtre
ADSR envelope generator for modulation of the cut-off frequency of VCFs.
Possibility of delay from 0 to 3 seconds in relation to the Keyboard Gate via
the Delay button
The Velocity button allows you to set the Sustain value according to the
velocity provided by the MIDI keyboard. It's up to the keyboard to provide
the right response curve.
The Retrigger button allows one play or each note press restarts the AD
cycle.
The Inv Button is used to invert the envelope which can be interesting for BP
or HP modes.

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SYNTHR3 Manuel V1.01 EN
ADSR VCA
ADSR envelope generator for the modulation of VCAs.
The Velocity button allows you to set the Sustain value according to the
velocity provided by the MIDI keyboard.
The Retrigger button allows one play or each note press restarts the AD
cycle.
The AutoRetrig Button allows the AD cycle to be repeated automatically
within a pressed note or active gate. The setting of the A and D values
determines the repetition frequency. To hear the effect, it is recommended
that you turn down the sustain. Decay remains active normally when
released.
* It's best to press only one of these buttons at a time, though !!!
Portamento
The adjustable portamento can be applied to either VCO1 or / and VCO2 and is
activated by the corresponding button.
OUTPUTS
VCAs
Special feature for the VCA1: It receives the Tuning fork when it is activated via the control screen (see below), and in this
case open the gain potentiometer.
The following is valid for both VCAs.
The gain control allows you to hear audio outside the envelope level. It will therefore generally be at 0 except when
listening to the pitch or playing drone.
The LFO2 potentiometer allows amplitude modulation in
addition to the gain or the envelope.
The envelope potentiometer adjusts the opening level of the
VCA.
The MIX potentiometer is used to send the output of the VCA to
outputs 1 or 2 of the synthesizer, to a mixer (line level).
WARNING: if the Gain and Envelope potentiometers are at 0 ther will be no output. Also do not forget the General Volume
potentiometer.
WARNING: In PARAPHONIC 2 mode the VCAS have different roles: The Gain potentiometer of the VCA1 is used to adjust the
input level in the VCF2 and the Gain potentiometer of the VCA2 is used for the output level. It is preferable in this case to set it
to full. The envelope potentiometers do not act.

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SYNTHR3 Manuel V1.01 EN
THE PLAY MODES
Depending on the play modes, some buttons are prohibited; don't be surprised if you can't operate them, it's normal
operation.
MONOPHONIC MODE FILTER IN PARALLEL
It's the play mode that allows for just about any combination:
VCOs and other sources can be sent to either filter or both at the same time. The sounds produced can be sent to either or
both line outputs.
In this mode there is only one possible note on the keyboard and therefore only one "Gate" that controls the 3 envelopes.
The filter envelope is sent on the 2 VCFs and the VCA envelope on the 2 VCAs. The Modulation envelope is free to use for FM,
PWM, LFO2 destinations.
VCOS can be synchronized, at different octaves or detuned …..
Reminder: SUB follows VCO1
This is still a bi-timbral play since each channel has its own VCF and VCA.

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SYNTHR3 Manuel V1.01 EN
MONOPHONIC MODE SERIAL FILTER
This mode is identical and does not require any action on the MIDI controller. Simply press the Serial Filter button located
under the VCF1.
However, nothing will be output through VCA1 and all the audio will be output through VCA2.
As the filters can be identical (2 low passes) or different, this mode allows you to sculpt a finely tuned sound thanks to the
action of the 2 successive filters.

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SYNTHR3 Manuel V1.01 EN
DUOPHONIC MODE
This mode allows a 2 notes play, one is played by the VCO1, the other by the VCO2. The VCO3 can be used too but it will be
driven like the VCO2 to the nearest chord between them. The SUB that follows VCO1 is also usable and can be sent to either
filter
The lowest note has priority and will be played by the VCO1, the second lowest note will be played by the VCO2.
Important :
In this two-tone duophonic mode the VCF1 and VCA1 together receive the modulation envelope. Be careful to open this
envelope otherwise there will be no sound. As for VCF2, it always receives the filter envelope and VCA2 the VCA envelope.

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SYNTHR3 Manuel V1.01 EN
PARAPHONIC 1 MODE
This mode allows for playing up to 3 notes, one is played by VCO1, the other by VCO2 and the third by VCO3. But there is only
one GATE for all 3 notes, so this play is particularly suitable for playing in 3-note chords.
When only one note is played the 3 VCOs, if tuned play the same note, if a second note is played without releasing the
first one the VCO2 and 3 play the same note and finally if a third note is pressed the VCO3 will play it.
The lowest note has priority and will be played by VCO1, the second pressed note will be played by VCO2 and the third by
VCO3..
The choice of filters is free.
Tip: Tuning the 3 VCOs in unison but above all not synchronizing them.

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SYNTHR3 Manuel V1.01 EN
PARAPHONIC 2 MODE
This mode allows you to play up to 3 notes in the same way as the previous mode but this time each VCO is controlled by a
hidden VCA to which one of the available envelopes is assigned. VCO1 will be controlled by the modulation envelope, VCO2
by the filter envelope and VCO3 by the VCA envelope. Each envelope will receive its corresponding gate for the note that is
pressed. This is to allow for a set of untied notes. We're getting closer to a polyphonic play.
The lowest note has priority and will be played by VCO1, the second pressed note will be played by VCO2 and the third by
VCO3.
Important :
The assembly is sent to VCA1 which, by its gain setting, allows the input level to be adjusted in VCF2. The envelope
potentiometer of this VCA1 is set to 0. The VCF2 is output by the VCA2 to which you will have to give some gain in order to
hear an output. The envelope potentiometer of VCA2 is at 0.
The level of each note is controlled by the Sustain of the respective envelope.
Last refinement instead of the VCO1, it is possible to send a mix of VCO1, SUB, RM, Noise for the 1st note via the
corresponding potentiometers and buttons of the Mixer.
Finally in this mode, the VCF2 receives on its envelope input an analog OR of each of the note envelopes. The filter can
therefore react on each played note.

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SYNTHR3 Manuel V1.01 EN
ARPEGIATOR MODE
This mode is based on the Duophonic Mode configuration, VCO1 is reserved for the Arpeggiator and VCO2 can either follow
it or be free to play on the keyboard. VCO3 follows VCO2. The SUB follows VCO1.
The detailed use of this mode is covered later with the use of the MIDI controller.
STEP SEQUENCER MODE
This mode uses the Duophonic or Paraphonic Mode 1 configuration. In Duophonic mode, VCO1 is reserved for the Sequencer
and VCO2 can either follow it or be free to play on the keyboard. VCO3 follows VCO2. In Paraphonic 1 mode, the 3 VCOs are
used to make SYNTHR3 a tuning sequencer, provided that all 3 VCOs are tuned in unison.
The detailed use of this mode is covered later with the use of the MIDI controller.
CONTROLLER MIDI USAGES
Now that you have gotten acquainted with the SYNTHR3, its analog part, its possibilities, we are going to go into the details
of how its brain works: the MIDI controller and its different MENUS.
We will see in detail how the last 2 Play Modes work, how to use the Tuning fork, how to choose your MIDI channel, and
above all how to save a "Patch" to find it quickly.
Bouton A Encodeur Bouton B
Led d’activité MIDI

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SYNTHR3 Manuel V1.01 EN
MONOPHONIC MODE
Channel:8 locked
Mastertune=A440
MidiRST Edit.
ARPEGGIATOR >0
OCT SWG DIR LFO VCO2
+2 50% <-> x2 cv1
Next ↕Arpeggio Esc
MIDI CONTROLLER FUNCTIONS
A control screen of 4 lines by 20 characters allows to use the SYNTHR3 by three commands located below the screen: The
first three lines always concern the current action and / or mode, the fourth line specifies the momentary role of the
commands located below.
These commands are :
a rotary encoder allowing to modify a numerical value and to validate it by a direct press on "OK".
A button in the left zone. This button will be called " Button A "
A button on the right-hand side. This button will be called "Button B".
Buttons A and B have variable functions depending on the situation, and these functions are recalled on the screen in the
lower right or left area, and throughout this manual.
Screen samples :
In the 1st screen, button A allows you to search for the MIDI channel in the 2nd screen it is used to move the cursor ">"
which allows you to modify the following parameter via the encoder.
In the 1st screen, button B is used to go to the next screen to choose another function, in the 2nd screen, it is used to exit the
current menu.
Under this controller we find the connections to the outside and not far from the Master Tune setting.
The MIDI In and Thru are self-explanatory, as for the "Polychain",
we will specify its role later on.
POWER UP
The first time the SYNTHR3 is turned on, once it has passed the home screen, it is positioned in the MONOPHONY game
mode. Afterwards, any changes applied by the user will be saved for the next power-up.
Screen organization
Once past the home screen, the screens are organized as follows:
From the screen of a game mode (main screen), you can go down to the functions using "Edit. "(Button B) and return with
Escape. Changing functions on the function bar is done with the encoder and OK for the selection.
The function selection area is called: "Function bar"».

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SYNTHR3 Manuel V1.01 EN
MONOPHONIC MODE
Channel: waiting
MasterTune=A440
midiRST Edit.
DUOPHONIC MODE
↕/Ok Escape
Change about ?
OPERATING MODE
↕/OK Escape
OPERATING MODE
From the main screen in any mode press EDIT (Button B) to access the function bar, rotate the encoder until it encounters
"OPERATING MODE", press OK and select the desired mode.
-Turn the encoder to change the
function.
-OK to select it
-Escape to go back
-Turn the encoder to change the
function.
-OK to select it
-Escape pour retourner en arrière
-Edit to go to the function bar