Retroaktiv MPG-50 User manual

USER’S MANUAL AND REFERENCE GUIDE
All rights reserved. 2021 Retroaktiv LLC.
Colorado, USA.

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FEATURESFEATURES
Independent control of any combina-
tion of 2 Alpha Juno or MKS-50 syn-
thesizers.
Control 2 units independently, or as a
single 12-voice polyphonic synthesiz-
er, using Multi-Unit Poly Mode.
On-board 32k of memory for storing
patches, MIDI matrices (ASSIGN), and
setups on the controller. MKI units
can be expanded to 128K of object
storage. MKII units ship with 32K on-
board, expandable to 160K.
Flexible MIDI matrix allows multiple
parameters to be controlled inde-
pendently in real-time, using af-
teouch, mod wheel or any CC, an
expression pedal, or the two ASSIGN
sliders on the MPG-50 front panel.
Chord mode for playing any combina-
tion of notes using a single key. (This
is different than AJ CHORD mode)
Store any PATCH with the push of
a buon. MPG-50 eliminates the
“shared-tones” system of saving
sounds on the MKS-50. Each MPG-50
PATCH is stored as one object.
Intelligent patch generator creates new
tones and patches at the push of a buon.
Choose from Basses, pads, bells, strings
and more.
CC to sysex translation allows for DAWs
and sequencers to record and playback
parameter changes on MPG-50 in
realtime. Each of the 2 layers on the con-
troller can be controlled independently by
CCs.
Each ASSIGN, PATCH, and SETUP can be
changed using program and bank change
messages. Independent control of all
layers.
MPG-50 allows users to store and name
custom CC maps, allowing users to create
their own custom control maps for other
gear using the MPG-50 panel.
Receive or transmit banks, individual
patches, or a full memory backup of all
stored user objects. Sysex utility allows
users to quickly load, store, and back up all
of their favorite soundbanks.
MIDI bootloader allows users to use sysex
files to update their MPG-50 allowing for
more new features to be added in the
future.

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FRONT PANEL & JACKSFRONT PANEL & JACKS
MIDI IN
PORT 1
MIDI OUT
PORT 1
MIDI IN & OUT
PORT 2
PASSIVE EXPRESSION
PEDAL JACK
DC ADAPTER 9 - 15v DC
CENTER PIN +, SLEEVE 0v
OLED DISPLAYOLED DISPLAY
OLED display presents information about the
operation being peormed.
OBJECT STORAGEOBJECT STORAGE
Use SHIFT+ASSIGN (STORE) to select a location to
store a PATCH, ASSIGN, or SETUP. Use SHIFT+CHORUS
(LOAD) to load a stored object.
L AYE RL AYE R
Use the MAIN (MAIN/AUX) buon to select the layer
to be edited (MAIN/AUX/BOTH).
ENCODER/(SHIFT)ENCODER/(SHIFT)
The black encoder knob located directly under
the OLED is used to modify values of the currently
selected parameter. If you hold down the encoder
[SHIFT] and turn the encoder, parameter values will
change by larger increments.
MENU NAVIGATION BUTTONSMENU NAVIGATION BUTTONS
The menu navigation buons are used to select
editor pages in the MPG-50. The [LEFT] and [RIGHT]
buons are used to move the cursor in the menu
pages.
The [ENTER] buon is used to execute a variety of
operations within a menu.
[MIDI], [PATCHGEN], [MAIN], and [ASSIGN] buons
are used to navigate to their respective menu
pages.
Special functions are accessed by pressing a buon
while holding [SHIFT].
JACKS & POWERJACKS & POWER
The power adapter jack and power switch are
located on the le side of the back of the unit. Use
only the adapter that came with the MPG-50.
MIDI IN = MIDI IN Po 1
MIDI OUT = MIDI OUT Po 1
MIDI IN/OUT = MIDI IN or MIDI OUT Po 2
Po 2 can function as either a MIDI IN or MIDI OUT,
depending on the MIDI PORT 2 seing in the MIDI:
Seings menu.

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CONNECTIONS & GETTING STARTEDCONNECTIONS & GETTING STARTED
SINGLE UNIT OPERATIONSINGLE UNIT OPERATION
To begin using your MPG-50 mkII, it’s impoant to set up proper MIDI communication between the
programmer and the synth. The most basic setup is to send the MIDI OUT from your DAW or MIDI controller, to
MIDI IN Po 1 of the MPG-50. The MIDI OUT Po 1 of the MPG-50 mk II is connected to the MIDI IN of the AJ/
MKS-50. The default state of the MPG-50 is for MIDI ECHO to be enabled. This means that MIDI data received
by the 50 on its MIDI IN will be immediately processed and passed OUT to the AJ/MKS-50. The figure below
shows a simple configuration of MPG-50
MKS-50 or ALPHA JUNO
MIDI IN
MIDI CONTROLLER OR DAW
To begin making sound, let’s sta by creating a basic setup. Press the [MIDI] buon on MPG-50 and set the
MPG-50 MIDI seings as shown below, and set the AJ/MKS-50 to receive on channel 1. Set Unit 1 to either
JUNO or MKS-50, depending on which you’re using. Enable EXCLUSIVE on the synth so it receives sysex from
the controller. Set your MIDI controller to send on channel 1. The synth should be receiving data from the
controller when a slider is moved, as well as when a key is pressed on your controller.
Basic MIDI menu seings on the MPG-50 mkII
Basic MIDI configuration

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Basic MIDI menu seings on the MPG-50 mkI
MKS/JUNO UNIT 1 (Ch 2)
MIDI IN
MIDI CONTROLLER (Ch 1)
MIDI OUT
MKS/JUNO UNIT 2 (Ch 3)
MIDI IN MIDI OUT
MIDI THRU
MULTI-UNIT OPERATIONMULTI-UNIT OPERATION
Basic MIDI configuration for 2 Unit Operation
MPG-50 can control 2 MKS/Juno units independently. Users can play the 2 Junos as a “STACK”, where the two
synths are layered, similar to the UPPER & LOWER tone architecture found on synths like MKS-80 and MKS-70/
Super JX. The two synths can also be daisy chained by using MPG-50’s Multi-Unit Poly Mode, which turns the
2 synths into a single 12-voice synth, effectively doubling the polyphony of an Alpha Juno. The figure below
shows the most basic connection scheme for multi-unit operation.

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To begin playing the synths in STACK mode, MIDI: Seings pages should be set as follows.
MPG-50 MIDI: Seings Unit 1 - “Stack” Mode
MPG-50 MIDI: Seings Unit 2 - “Stack” Mode
MPG-50 MIDI: Global Seings - “Stack” Mode
Note that Unit 1 and Unit 2 Input Ch is set to channel 1 on both units. This means that the MPG-50 is listening
for notes and control data on channel 1 on both units. It a note comes in on channel 1, then it will trigger a
sound on both synths. Notice that the Output Ch on Unit 1 is set to channel 2, and the Output Ch on Unit 2
is set to channel 3. MKS/Juno Unit 1 is set to receive on channel 2, and MKS/Juno Unit 2 is set to receive on
channel 3. When playing in STACK mode, the VOLUME slider can be used as a CROSSFADE slider. Be sure that
OMNI is OFF on both units to use this. Go to MAIN screen and move the VOLUME slider to select it. Click the
USING TWO UNITS IN ‘STACK’ MODEUSING TWO UNITS IN ‘STACK’ MODE

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SHIFT buon once, and the screen will now display CROSSFADE. Moving the slider up and down will crossfade
between unit 1 and 2.
USING TWO UNITS IN MULTI-UNIT POLY MODEUSING TWO UNITS IN MULTI-UNIT POLY MODE
When in Multi-Unit Poly Mode, the 2 units become a single 12-voice synthesizer. This means rather than
stacking two 6-voice synths over each other, we load the same sound onto both, and use them as a 12-voice
synthesizer. The Unit 1 and Unit 2 MIDI: Seings are the same as in STACK mode. The only change is that
MULTI-UNIT POLY MODE is set to ON.
MPG-50 MIDI: Seings Unit 2 - Multi-Unit Poly Mode

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MENUS AND NAVIGATIONMENUS AND NAVIGATION
The MPG-50 will boot up and display the MAIN menu screen. The diagram below shows the contents displayed
on the MAIN screen.
MPG-50 Navigation Console
MPG-50 MAIN Screen
The MAIN screen displays the following information:
1 - Current active parameter name and value
2 - Unit: The box in the lower le corner of the screen displays the unit currently being controlled by the MPG.
3 - Oct: The center box on the boom of the MAIN screen shows the current octave transposition seing.
4 - MIDI Input Monitor - Displays channel of incoming MIDI activity received at MPG-50 MIDI IN po.
To return to the MAIN screen at any time, press the [MAIN] buon in the navigation console. Pressing MAIN
repeatedly will cycle between editing the MAIN, AUX, or BOTH synths. SHIFT + MAIN will also toggle the layer.
The encoder and arrow buons are used to navigate menus and change seings. The SHIFT function refers
to the switch on the encoder knob. To engage the SHIFT function (used for double-buon combos such as
SHIFT+MIDI buon = MIDI Panic), press and hold the encoder knob. To increment a value with the encoder,
simply turn the encoder knob. To increment or decrement by 8, hold the SHIFT buon in while turning the
encoder.
Use the [MIDI], [PATCHGEN], [ASSIGN], and [MAIN] buons to navigate to the different menu pages. To move
the cursor on a menu page, use the [LEFT] and [RIGHT] buons. To change the value of a highlighted menu
seing, use the [ENCODER] dial.

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VOLUME AND CROSSFADE FADERVOLUME AND CROSSFADE FADER
The VOL & X-FADE slider on the front panel allows users to either set the master volume of the MKS-50 (When
in volume mode) or it can crossfade between UNIT 1 and UNIT 2. When used as a VOLUME slider, this will send
CC#7 (Volume) messages to each MKS-50. If used as an X-FADE slider, the fader will crossfade between UNIT
1 and 2, with the volume level of each MKS-50 being equal when the fader is at 50%. Both synths must have
OMNI turned OFF for CROSSFADE to work.
To toggle the VOLUME/X-FADE mode: From MAIN screen, move VOLUME slider to select it. Click [SHIFT] toTo toggle the VOLUME/X-FADE mode: From MAIN screen, move VOLUME slider to select it. Click [SHIFT] to
toggle between VOLUME and CROSSFADE.toggle between VOLUME and CROSSFADE.
IMPORTANT SHORTCUTSIMPORTANT SHORTCUTS
It will be useful to memorize the following editing shocuts.
TONE & PATCH SHORTCUTSTONE & PATCH SHORTCUTS
[SHIFT] + [GLIDE] = toggle KEY ASSIGN MODE (MONO/POLY/CHORD)
[SHIFT] + [LEFT] = TRANSPOSE OCTAVE DOWN
[SHIFT] + [RIGHT] = TRANSPOSE OCTAVE UP
PATCH GENERATOR SHORTCUTSPATCH GENERATOR SHORTCUTS
[SHIFT] + [PATCHGEN] = Generate a random tone
[PATCHGEN] = Mask all sections/Unmask all sections
MIDIMIDI
[SHIFT] + [MIDI] = MIDI panic
ASSIGNASSIGN
[SHIFT] + [PATCHGEN] = Clear all assigns
STORAGESTORAGE
[SHIFT] + [PATCHGEN] = Delete bank
[SHIFT] + [CHORUS] = Increment bank
USER CCUSER CC
[SHIFT] + [PATCHGEN] = Delete current CC map
[SHIFT] + [CHORUS] = Load a new USER CC MAP
[SHIFT] + [ASSIGN] = Store a new USER CC MAP
FREEZE FUNCTIONFREEZE FUNCTION
Pressing ENTER from the MAIN screen will enable the “FREEZE” function on MPG-50. When FREEZE is enabled,
a message will be displayed “Freeze : ENTER to send.”. When FREEZE is on, moving a slider will not send a
message. When ENTER is pressed, the new location of any slider moved during the FREEZE operation will be
sent to the synth. This is an excellent way to send a large number of slider changes all at once, at the exact
moment ENTER is pressed.
“PEEK” MODE“PEEK” MODE
If you want to see that a slider value is currently set to, navigate to the desired layer, then hold SHIFT while
moving the slider. The current value of the slider will be displayed on the screen, and it will not change when
moved. This allows you to safely check the state of any control in a PATCH or TONE without changing the
original value.

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USING ENCODER TO SCROLL THROUGH PRESETS ON SYNTHUSING ENCODER TO SCROLL THROUGH PRESETS ON SYNTH
MPG-50 allows users to use the encoder to scroll through presets on the MKS/Juno. To do this, press MAIN
buon to return to the MAIN screen, and press the LEFT buon once. This will navigate to the MAIN: PresetMAIN: Preset
SelectSelect menu. Scrolling through the PRESET SELECT menu will allow you to scroll through the sounds on the
MKS/Juno usit using the encoder on the MPG-50.
MANUAL MODEMANUAL MODE
To send the current slider and buon seings on the front panel to the synth, go to the MAIN menu by
pressing [MAIN]. Now press [SHIFT] + [ENTER]. A dialog box will pop up, reading “Sending all control positions”.
PATCH M ENUPATCH M ENU
The Alpha Juno and MKS-50 each have a PATCH MENU, which contains the seings for the synth which are not
accessible from the front panel sliders. To navigate to the PATCH PARAMS menu, press MAIN to return to the
MAIN screen, and press the RIGHT buon. The PATCH PARAMS menu will be displayed based on which type of
unit (MKS or JUNO) the currently selected layer is set to.
Alpha Juno PATCH PARAMS menu contains:
•• Key ModeKey Mode - Mono/Poly/Chord (These can also be toggled using SHIFT+GLIDE)
•• Bend RngBend Rng - Sets Alpha Juno bend range
MKS-50 PATCH PARAMS menu contains:
•• Key ModeKey Mode - Mono/Poly/Chord (These can also be toggled using SHIFT+GLIDE)
•• Key ShiKey Shi - Transposes MKS-50 by half-steps
•• Key Range LowKey Range Low - Sets lowest note on MKS-50
•• Key Range HighKey Range High - Sets highest note on MKS-50
•• VolumeVolume- Sets MIDI volume of MKS-50
•• TuneTune - Fine tuning of MKS-50
•• Mod SensMod Sens - Sets mod wheel sensitivity
•• BendBend- Sets pitch wheel sensitivity
•• Chord MemChord Mem - Selects the MKS-50 CHORD from MKS-50 memory
•• VolVol- enables volume messages on MKS
•• PoPo- Enables GLIDE on MKS
•• ModMod - Enables Mod Whl on MKS
•• HoldHold - Enables Sustain Ped on MKS
•• BendBend- Enables Pitch Whl on MKS
•• AeouchAeouch - Enables aeouch on MKS