AnalogFX SER-2020 User manual

USER MANUAL
SER-2020
DESKTOP MODEL REV2.0

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THANK YOU FOR CHOOSING THE SER-2020.
Congratulations on your ownership of the AnalogFX SER-2020 analog synthesizer with formant
filter, one of the most exciting and versatile instruments used in electronic music. Based on
the legendary Synton Syrinx1which was used by Aphex Twin, Air, Depeche Mode and many
more. Connect SER-2020 directly to any MIDI controller and immediately access a world of
powerful analog sound, or hook up to a MPE device to explore even deeper layers of sound
creation. The SER-2020 will bring you many hours of happy and creative sonic enjoyment. We
are sure you are anxious to start playing, so refer to the “Installation” guide to get started
Thank you.
Manual Applicable for;
PN: 200 002 000 V2.0A

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INDEX
IMPORTANT SAFETY INSTRUCTION............................................................................................ 4
DANGER .................................................................................................................................. 5
CAUTION................................................................................................................................. 5
LEGAL DISCLAIMER................................................................................................................. 5
1INTRODUCTION .................................................................................................................. 6
2INSTALLATION .................................................................................................................... 7
2.1 SET UP .......................................................................................................................... 7
2.2 CONNECT TO POWER & MIDI ...................................................................................... 7
2.3 POWER UP ................................................................................................................... 8
2.4 WARM-UP AND GENERAL TUNING ............................................................................. 8
2.5 CONNECT TO AMPLIFIER ............................................................................................. 8
2.6 START PLAYING ............................................................................................................ 8
3GENERAL DESCRIPTION ...................................................................................................... 9
3.1 LFO AND BENDPAD SECTION....................................................................................... 9
3.1.1 CONTROLS ............................................................................................................ 9
3.1.2 INPUT AND OUTPUTS ......................................................................................... 11
3.2 CONTROL & MODULATION........................................................................................ 12
3.2.1 CONTROLS .......................................................................................................... 12
3.2.2 INPUTS AND OUTPUTS ....................................................................................... 13
3.3 VCO SECTION ............................................................................................................. 14
3.3.1 VCO CONTROLS .................................................................................................. 14
3.3.2 VCO INPUT AND OUTPUTS ................................................................................. 15
3.4 MIXER AND ROUTING SECTION ................................................................................. 16
3.4.1 MIXER CONTROLS............................................................................................... 16
3.4.2 MIXER INPUTS .................................................................................................... 16
3.5 VCF SECTION .............................................................................................................. 17
3.5.1 VCF CONTROLS ................................................................................................... 17
3.5.2 VCF INPUTS AND OUTPUTS ................................................................................ 19
3.6 ADSR SECTION ........................................................................................................... 20
3.6.1 ADSR CONTROLS................................................................................................. 20
3.6.2 ADSR INPUTS AND OUTPUTS ............................................................................. 20
3.7 SAMPLE AND HOLD SECTION .................................................................................... 21
3.8 SPEECH MODE ........................................................................................................... 22
3.8.1 ENABLE SPEECH MODE AND ALLIGN THE PEAK FILTERS.................................... 22
3.8.2 PROGRAM SPEECH MODE.................................................................................. 22
3.9 INPUTS & OUTPUTS ................................................................................................... 23
3.10 KEYBOARD CONTROL ............................................................................................. 23
3.11 VCO AUTO TUNE .................................................................................................... 24
3.12 MIDI control ........................................................................................................... 25
3.12.1 MPE .................................................................................................................... 25
3.12.2 VCA ROUTING..................................................................................................... 25
3.12.3 DYNAMIC MODE................................................................................................. 25
3.12.4 MIDI CONFIGURATION ....................................................................................... 26
3.12.5 MPE CONFIGGURATION MESSAGE .................................................................... 29
3.12.6 CONTROL PARAMETERS ..................................................................................... 30

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3.12.7 MIDI IMPLEMENTATION CHART......................................................................... 31
4SPECIFICATION ................................................................................................................. 32
5SERVICE AND SUPPORT INFORMATION ........................................................................... 34
5.1 LIMITED WARRANTY.................................................................................................. 34
5.2 RETURNING YOUR PRODUCT TO ANALOGFX ............................................................ 34
5.3 CARING FOR THE SER-2020 ....................................................................................... 34
6LEGAL NOTES.................................................................................................................... 35
6.1 NO LIABILITY FOR CONSEQUENTIAL DAMAGES ........................................................ 35
6.2 ELECTROMAGNETIC COMPATIBILITY (EMC).............................................................. 35
6.3 EUROPE...................................................................................................................... 35
APPENDIX A - CALIBRATION ..................................................................................................... 36
BEND PAD OFFSET ................................................................................................................ 36
HIGH FREQUENCY LINEARITY ............................................................................................... 36
PULSE WIDTH ....................................................................................................................... 36
LFO SYMMETRY .................................................................................................................... 36

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IMPORTANT SAFETY INSTRUCTION
This symbol wherever it appears, alerts you to the presence of uninsulated
dangerous voltage inside the enclosure – voltage that may be sufficient to
constitute
This symbol, wherever it appears, alerts you to important operating and
maintenance instructions in the accompanying literature. Please read the manual
1. Read this instruction and keep these instructions.
2. Heed all warnings and follow all instructions.
3. Do not use this apparatus near water, rain or moisture.
4. Do not place naked flame sources, such as lighted candles, on the apparatus.
5. Do not clean with solvent based or abrasive cleaners. Clean only with dry cloth.
6. Do not block any ventilation openings. Install in accordance with the manufacturer’s
instructions.
7. Do not install near any heat sources such as radiators, heat registers , stoves, or other
apparatus that produce heat.
8. Do not install in a confined space, such as a book case or similar units.
9. Do not over-tighten the screws, nuts and stand-offs provided.
10. Do not over-turn the control knobs (they are analogue potentiometers, which have end stops)
or over-push the toggle switches.
11. The PCB of individual not assembled Euro-rack modules may contain sharp edges and sharp
points. Keep away from young children.
12. Do not reverse the power connector. And only use the provided power supply or power cord.
13. Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has
two blades with one wider than the other. A grounding-type plug has two blades and a third
grounding prong. The wide blade or the third prong are provided for your safety. If the
provided plug does not fit into your outlet, consult an electrician for replacement of the
obsolete outlet.
14. Protect the power cord from being walked on or pinched particularly at plugs, convenience
receptacles, and the point where they exit from the apparatus.
15. Use only attachments or accessories specified by the manufacturer.
16. Use only with the cart, stand, tripod, bracket, or table specified by the
manufacturer, or sold with the apparatus. When a cart is used, use
caution when moving the card or apparatus combination to avoid injury
from tip-over.
17. Unplug this apparatus during lightning storms or when the apparatus is
unused.
18. Refer all servicing to qualified service personnel. Servicing is required
when:
a. Liquid has been spilled or objects have fallen into/onto the apparatus.
b. The power supply cord or plug is damaged.
c. The apparatus has been exposed to rain or moisture.
d. The apparatus does not operate normally or exhibits a marked change in performance.
e. The apparatus has been dropped or the enclosure is damaged.
19. The apparatus shall be connected to a Mains socket outlet with a protective earthing
connection.

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20. Where the Mains plug or an appliance coupler is used as the disconnect device, the disconnect
device shall remain readily operable.
21. Correct disposal of this product: This symbol indicates that this product
must not be disposed of with household waste, according to the WEEE
Directive (2012/19/EU) and your national law. This product should be taken
to a collection center licensed for the recycling of waste electrical and
electronic equipment (EEE). The mishandling of this type of waste could
have a possible negative impact on the environment and human health due
to potentially hazardous substances that are generally associated with EEE.
At the same time, your cooperation in the correct disposal of this product
will contribute to the efficient use of natural resources. For more information about where
you can take your waste equipment for recycling, please contact your local city office, or your
household waste collection service.
22. This apparatus, in combination with an amplifier and headphones or speakers, may be capable
of producing sound levels that could cause permanent hearing loss. Do not operate for a long
period of time at a high volume level or at a level that is uncomfortable.
23. Please keep the environmental aspects of battery disposal in mind. Batteries must be
disposed-of at a battery collection point.
24. Use this apparatus in moderate climates. Operate at between 0 °C to +40 °C, <95% Relative
humidity (non-condensing).
DANGER
INSTRUCTIONS PERTAINING TO RISK OF FIRE, ELECTRICSHOCK, OR INJURY TO
PERSONS: Do not open the chassis. There are no user serviceable parts inside. Refer
all servicing to qualified personnel only.
CAUTION
To reduce the risk of fire or electric shock, do not expose this appliance to rain and
moisture. The apparatus shall not be exposed to dripping or splashing liquids and
no objects filled with liquids, such as vases, shall be placed on the apparatus.
LEGAL DISCLAIMER
AnalogFX accepts no liability for any loss which may be suffered by any person who relies
either wholly or in part upon any description, photograph, or statement contained herein.
Technical specification, appearance and other information are subject to change without
notice. All trademarks are property of their respective owners.
©AnalogFX 2021 All rights reserved.

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1INTRODUCTION
The SER-2020 is a monophonic semi-modular analog synthesizer with a formant filter section,
designed to use as standalone synthesizer or in combination with Eurorack modules. Inspired
by the famous classic Synton Syrinx1synthesizer, we added the flexibility of an patch panel
and made it compatible with Eurorack CV’s. The filter features a combination of a 24dB/octave
VC Low Pass Filter, and two independent Resonant VC Peak Filters for dynamic sound shaping.
The sound is ranging from solid bass sounds to articulated formant effects. We added MPE
(MIDI Polyphonic Expression) capabilities to make the SER-2020 a dynamic instrument which
responses to its player. The flexible routing by the patch panel makes the SER-2020 a versatile
synth for sound effects. So connect your MPE controller and GO.
Key Specifications:
Semi Modular Setup - CV inputs and outputs
2 VCO's (CEM3340 based)
1 Sub-Oscillator
Ring Modulator
Noise Generator
Audio Mixer
Multi-Mode Sync & Sync D-Tune
3 VCF's (CEM3350 based)
Speech Mode, for easy formants programming.
VCA (CEM3360 based)
2 ADSR's
2 LFO's with Reset & Shaper Modes
Auto-Glide
Multiple Triggering
Touch 'N Bend Pad
Bend Assign
Sample and Hold
Auto tune of VCO’s
Signal and Headphone output.
MIDI interface
USB MIDI interface
MPE compatible - Sensitive for: Strike (note-on velocity), Press (aftertouch), Glide
(pitch bend), Slide (brightness) and Lift (note-of velocity).
1Synton Syrinx is used to associate the sound of this module and is not correlated with AnalogFX.

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2INSTALLATION
For those of you who can’t wait to play your new SER-2020, the following should get you set up and
running quickly.
NOTE: Please read the entire manual to learn more about the instrument and gain a better
understanding of what you can do with the SER-2020.
Check the contents in the shipping carton
The SER-2020 is shipped with the following items:
1. The SER-2020 Synthesizer.
2. A 12VDC Power Adaptor.
3. User’s Manual.
4. USB cable to connect the SER-2020 to a host computer, for USB MIDI.
What you will need
In addition you will need:
1. A sturdy surface to support the SER-2020
2. A MIDI keyboard, MIDI controller or MPE controller.
3. A MIDI cable.
4. A 6.35 mm (1/4'') instrument cable and amplifier, or a pair of headphones.
2.1 SET UP
Make sure you have an adequate place to set up. Do not expose your SER-2020 to dripping or splashing
and no objects filled with liquids, such as vases, should be placed on top of it.” Use care when
unpacking the SER-2020,and be sure to save the carton and all packing material in case you need to
ship the SER-2020 for any reason.
Here is an overview of the SER-2020 synthesizer’s connectors on the back side:
Audio : Outputs 6.35 mm (1/4'') mono jack.
Headphone : Outputs 6.35 mm (1/4'') stereo jack.
USB : Standard USB type B.
MIDI Input &Thru : Standard MIDI DIN-5.
Power DC Input: Internal 2.1 mm, external 5.5 mm. (Ring negative, tip positive.)
2.2 CONNECT TO POWER & MIDI
Connect the Power Adaptor to a properly-wired wall outlet and connect the 12VDC power jack to the
back of the unit. The universal power supply will operate with a power source from 100 to 250 Volts
AC, 50/60Hz. Using a standard MIDI cable to make the connection between the MIDI OUT of your MIDI
controller and the MIDI IN on the SER-2020. The standard MIDI setting from the factory is set to MPE
mode, in this mode the SER-2020 receive messages on MIDI Channel 1 to 16. If you are using USB MIDI
with a Windows or Macintosh computer, connect the USB cable from the back panel of the SER-2020
to a USB port on your computer. The SER-2020 USB is automatically installed as HID driver, the SER-
2020 will appear as ’SER-2020’ in the MIDI device selection of your MIDI software.

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2.3 POWER UP
Enable the power switch on the back of the SER-2020 to switch it on. The power (PWR) LED on the
front panel will light up and the LED’s of the LFO’s start blinking. The SER-2020 is now operational and
ready for use.
2.4 WARM-UP AND GENERAL TUNING
As with all other analog synthesizers, after being powered-on the SER-2020 needs a warm-up period.
Although the SER-2020 has temperature compensated Voltage Controlled Oscillators (VCO’s) it is still
recommended to use a warm up period of about 10 minutes before using the synthesizer. This allows
reaching a stable operating temperature, which insures accurate oscillator pitch. The warm up period
may be longer if the synthesizer has been stored outside the recommended operating temperature
range.
Once the synthesizer has reached its running temperature, tune it to pitch. Use the internal 440Hz
tone or an external tuner to check the instrument’s tuning. If required, use the MASTER TUNE – FINE
knob to tune the SER-2020 to the desired pitch.
The SER-2020 has been designed for an operating ambiance temperature between 20°C and 35°C. The
SER-2020canoperation over a much wider temperature range, although extreme external
temperatures or fluctuations can lead to longer stabilization time or the Voltage Controlled Oscillators
(VCO’s) may not remain in tune. It is recommended that the case is not be exposed to direct sunlight
while operating the unit, the tuning of the VCO’s may be affected.
2.5 CONNECT TO AMPLIFIER
Always power-off all audio gear before making any connections. Failing to do so may damage your
speakers, the SER-2020 synthesizer, or other audio equipment.
Set the SER-2020volume control levels to 0 before connecting to an amplifier or headphones. Power
on the various devices, with audio amplifier or monitoring system last. Slowly bring up the SER-2020
volume to a comfortable listening level.
2.6 START PLAYING
The SER-2020 operates in the normal note range (MIDI notes 24 - 96). This means that the SER-2020
will respond to your playing from ‘C7’downward to ‘C1’. With the octave switch the range can be
transposed to one octave lower or maximum two octaves up. Play some notes, tweak the knobs and
have fun!

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3GENERAL DESCRIPTION
3.1 LFO AND BENDPAD SECTION
3.1.1 CONTROLS
LFO 1 RATE: Frequency control of LFO 1. The LFO offer a frequency range from 0.05Hz to 20Hz typically.
The LFO's can be reset every ‘note on’ by use of the TRIG switch so that modulation always will start
at the same point. Optional the LFO can be reset by the MIDI clock.
LFO 2 RATE: Frequency control of LFO 1. The LFO offer a frequency range from 0.05Hz to 20Hz typically.
When LFO 2 is in the ‘ONE SHOT’ mode, this LFO acts as an Attack / Release Generator. The LFO's can
be reset every ‘note on’ by use of the TRIG switch so that modulation will always start at the same
point. Optional the LFO can be reset by the MIDI clock.
SHAPE: Control for the shape of LFO 2. The triangle wave can be adjusted between a ramping up or
down sawtooth, at the same time providing pulse outputs with a duty cycle variation between 5% and
95%.

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A440: Switches the noise source between white noise or a clean 440Hz tone for tuning purpose. The
audio level of this signal can be set with noise control knob on the audio mixer.
TOUCH ‘N BEND: Bend pad for controlling the VCO, VCF or VCA by use of
the bend assign controls, see section 3.2. Also the LFO can be controlled by
the bend pad. The bend pad output also reacts on the MIDI modulation,
MIDI aftertouch and MIDI brightness (CC#74) messages (see table Table 1
for settings).
RATE CNTRL:LFO 2 rate control switch allows the Pad to control the speed
of LFO 2 between +/- 2 octaves. Switch UP is on, switch DOWN is off.
OUT: Volume control of the line output.
PORTAMENTO: Portamento (glide) control, the gliding effect occurs when
the keys are played legato. When the keys are played with only a few
milliseconds between notes, the glide effect is off, this is called auto
portamento. Glide time over 1 octave between 5 milliseconds and 1
second.
AUTO: Switch to enable the portamento mode. When switch is UP the auto
portamento (glide) is enabled, when switch is DOWN the portamento
(glide) is disabled.
TRIG: Multi triggering switch provides a new trigger pulse, which resets the
LFO’s, every time a key is hit regardless if a higher key is still depressed.
Switch UP is on, and switch DOWN is off. Optional both LFO´s can be reset
by the MIDI clock.
1 SHOT: Switch to enable the ‘ONE SHOT’ mode. LFO 2 will be restarted once each time a key is
depressed. In this case the LFO acts as an Attack / Release generator. When the switch is UP the ‘ONE
SHOTE’ mode is enabled, when switch is DOWN the ‘ONE SHOT’ mode is disabled.

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3.1.2 INPUT AND OUTPUTS
INPUTS
CV IN : External CV input. This CV input can be routed to the internal pitch CV or Bend
Pad CV. This can be set by MIDI CC message (CC#88), see table 1. The Pitch CV
is quantized to 1 semi-tone. Note: When using this input as pitch CV the MIDI
note events overrules the external CV input. If MIDI active sense is used this
input is disabled during connection with a midi device.
GATE IN : External gate input. This input can be used to trigger de ADSR’s generators and
to reset the LFO’s. Note: The MIDI note event overrules the external gate
input.
OUTPUTS
CV OUT : Internal CV output. Internal pitch CV from the internal MIDI to CV converter
routed to the VCO’s and VCF. Sensitivity of 1 Volt per octave (V/oct), range is
from 0 to 8 Volt.
GATE OUT : Gate output. Internal gate from the MIDI to CV converter. Level from 0 to 5
Volt. 0 Volt is gate off, 5 Volt is gate on.
BND OUT : CV output of the Bend Pad. Nominal output is 0 Volt.
LFO1:
TRI OUT : Triangle wave output of LFO 1. Output level between 0 and 5 Volt.
SQR OUT : Square wave output of LFO 1. Output level between 0 and 5 Volt.
LFO2:
TRI OUT : Triangle wave output of LFO 2. Output level between 0 and 5 Volt.
PLS OUT : Pulse wave output of LFO 2. Output level between 0 and 5 Volt.
TRI BND OUT : Triangle wave output of LFO 2 multiplied by the CV of the Bend Pad. The level
of this triangle wave output is controlled by the bend pad.

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3.2 CONTROL & MODULATION
3.2.1 CONTROLS
MASTER TUNE:
FINE: Tune control for both VCO’s. Fine tuning is over a range of
+/-8 semi-tone.
OCTAVES: Transpose switch for both VCO’s, select between -
1/0/+1/+2. When both ‘OCTAVES’ and ‘OCTAVE’ switches are on
‘0’, VCO 1 and VCO 2 are in their zero position and the A4key on
the keyboard can be tuned to 440 Hz.
BEND ASSIGN(BND ASN):
VCO: Bend pad control assign to the VCO. By turning this knob clockwise the VCO
frequency is controlled by the bend pad or midi message (modulation, aftertouch or
CC#74). Pitch bending with the Pad can be controlled over a 4 octave range. Note that
both VCO’s are controlled simultaneously when the VCO’s are not in sync or in soft
sync mode. In hard sync mode only one VCO is controlled.
VCF: Bend pad control assign to the VCF. By turning this knob clockwise the VCF cut-
off frequency and the frequency of the bandpass filters is controlled by the bend pad
or midi message (modulation, aftertouch or CC#74). A maximum control range over 8
octaves up or down can be covered when the bend pad is assigned to the VCF section.
VCA: Bend pad control assign to the VCA. By turning this knob clockwise the VCA is
controlled by the bend pad or midi message (modulation, aftertouch or CC#74). VCA
pad action is between 0% and 100%.

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FREQUENCY MODULATION (FM):
LFO 2 TRIANGLE: Modulation level for both VCO’s. A maximum of 6 semi-tones can be
modulated by the triangle wave.
LFO PULSE: Modulation level for both VCO’s. A maximum of 2 octaves can be
modulated by the square/pulse wave. When the external Frequency modulation input
is used, this knob is used to set the amount of external modulation.
VCA:
GAIN/MOD: Initial gain control of the VCA. This control allows for listening to the
synthesizer without any key being depressed, which can be convenient when a routing
or filter setting has to be made. Note: when ‘MPE mode’ is enabled this knob can be
used for tuning the VCA to the best dynamic performance. When the external VCA
Modulation input is used this knob controls the level of modulation to the VCA.
3.2.2 INPUTS AND OUTPUTS
INPUTS
VCA MOD : External VCA modulation input. This input is routed to the VCA GAIN/MOD
knob.
FM IN VCO 1 & 2 : External VCO frequency modulation input. This input is routed to the LFO 2
Square FM knob.

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3.3 VCO SECTION
3.3.1 VCO CONTROLS
VCO1
Total frequency range of VCO 1 is from 10Hz to 20KHz.
SYNC: Control for VCO synchronization, VCO 2 can be synchronized to VCO 1 in three
different modes: SOFT, HARD-Pulse and HARD-Sawtooth. In both hard modes only one
VCO is de-tuned by the Pad or MIDI command for special coloration effects.
SHAPE: Wave SHAPE selector for: Triangle wave, Sawtooth wave, Square wave and
pulse outputs. Pulse Width Modulation (PWM) can be effected in two modes with
respective trip points at 50% Square wave an 10% Pulse wave.
PWM/LFO 2:Independent PWM amount control of LFO 2 routed to the Square wave
or Pulse wave. The pulse width can be varied between approximately 10% and
90%.Since both VCOs have a separate LFO for PWM, chorus-like effects can be
obtained by controlling both pulses with different LFO speeds.

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VCO2
INTERVAL: Control for interval of VCO 2, a fifth up or down. When the control
indicates zero, as well as the OCTAVE selector, both VCO 1 and 2 are in unison.
OCTAVE: The octave transpose switch; -1/0/+1/+2 octave.
SHAPE: Wave SHAPE selector for: Triangle wave, Sawtooth wave, Square wave and
pulse wave. Pulse Width Modulation (PWM) can be effected in two modes with
respective trip points at 50% Square wave a 10% Pulse wave.
PWM/LFO 1:Independent PWM amount control of LFO 1 routed to the Square wave
or Pulse wave. The pulse width can be varied between approximately 10% and 90%.
3.3.2 VCO INPUT AND OUTPUTS
INPUTS
CV IN VCO2 : CV input for VCO 2, to control VCO2 separately from VCO 1. When using this
input the internal CV is disconnected from VCO 2.
OUTPUTS
VCO1 : Output of VCO 1 after the Waveform switch.
VCO2 : Output of VCO 2 after the Waveform switch.
NOISE : Direct output of the noise source (White Noise).
SUB : Direct output of Sub-oscillator of VCO1.

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3.4 MIXER AND ROUTING SECTION
3.4.1 MIXER CONTROLS
MIXER:
VCO 1: Audio level of VCO 1.
VCO 2:Audio level of VCO 2.
SUB 1: Audio level of the sub-oscillator, this
generates a frequency one octave below the pitch
of VCO1. The output signal of SUB 1 is a square
wave.
RM: Audio level of the Ring-Modulator or audio
level of the external filter input. The ring
modulator multiplies the Triangle wave of VCO 1
with the Triangle wave of VCO 2. When external
filter input is used this knob controls the audio
level of the external input and the ring-modulator
is disabled.
NOISE: Audio level of the Noise Generator (White Noise). With the A440 switch this output generates
a clean 440Hz signal usable to tune the VCO’s.
ROUTING:
VCF RTNG: Filter routing switch which cascades or parallels both filter
section and also provides different routing for the mixer input signals;
- (A) First mode : Both peak filters and the lowpass filter are in series.
- (B) Second mode : Both filter sections parallel.
- (C) Third mode : The signals from VCO 1, VCO 2 and SUB 1 will be processed by the low pass
filter only. The signals of the Ring Modulator (RM) and the Noise Generator
(NSE) will be processed by the peak filter and the low pass filter.
- (D) Fourth mode : The signals of the Ring Modulator (RM) and the Noise Generator (NSE) will be
processed by the peak filters. The signals from VCO 1, VCO 2 and SUB 1 will be
processed by the low pass filter.
3.4.2 MIXER INPUTS
VCF IN : VCF input for external audio signals. This input disables the ring-modulator.

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3.5 VCF SECTION
3.5.1 VCF CONTROLS
FREQUENCY:
PEAK 1 / PEAK 2:Frequency control for peak filter 1 and for peak filter 2.
LPF: Frequency control for the low-pass filter.
RESONANCE:
PK 1 / PK 2:Resonance control for peak filter 1 and for peak filter 2. The band width for peak 1 and 2
for minimal resonance is greater than 3 octaves, and for maximum resonance less than 1 semi-tone.
LPF: Resonance control for the low-pass filter.
FM PK 1&2:
Since both peak filters are controlled simultaneously, there is only one modulation control section.

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LFO 2 / EXT. MOD: Modulation control of both peak filters by LFO 2, which means that both peak
frequencies always will move in the same direction according to the interval which is set by the two
Frequency controls. Maximum LFO control range for PEAK 1 and 2 is 8 octaves up. When the external
modulation input is used this knob controls the level of modulation.
ADSR 1:Control from ADSR 1 to the peak filters. In the center position (0) there will be no modulation.
Turning the knob clockwise will result in "positive" modulation. The filter frequencies will first be
shifted up during the Attack status, then it will return to the preset frequencies in the Decay and
Release modes. Turning the knob anti-clockwise will result in "negative" modulation, which means that
the frequency will be shifted down first, and after that will go up and return to the pre-set value. The
peak filters can be controlled over 8 octaves up or down by ADSR 1.
KBD TRK PEAK 1 & 2: Control for keyboard tracking. Keyboard tracking can be adjusted between zero
(no tracking) and 2, in this case for every octave on the keyboard the filter is shifted over two octaves.
A common situation is that this control is on 1, which means that the filter frequency will track the
VCO frequencies. This is also convenient when resonant peaks have to track fundamentals.
FM LPF:
LFO 2 / EXT MOD: Modulation control for the low-pass filter. Here also positive and negative
modulation can be obtained by turning the knob right or left from its center zero position. This has
been supplied in order to create the possibility to modulate peak 1 and 2 and the LPF in opposite
directions. Maximum LFO control range for the low pass filter 8 octaves up or down. When the external
modulation input is used this knob controls the level of modulation.
ADSR 1:Control from ADSR 1 to the low-pass filters. In the center position (0) there will be no
modulation. Turning the knob clockwise will result in "positive" modulation. The filter frequencies will
first be shifted up during the Attack status, then it will return to the preset frequencies in the Decay
and Release modes. Turning the knob anti-clockwise will result in "negative" modulation, which means
that the frequency will be shifted down first, and after that will go up and return to the preset value.
The low-pass filter can be controlled over 8 octaves up or down by ADSR 1.