learning control knobs on AKAI MPK Mini IV with Reaper

[scottsknoll-arch]

bought a new MPK Mini IV. Connected to the USB-C on my Win 11 laptop's USB-C port. Installed the AKAI sw and updated firmware. The instrument part works fine in reaper. Picked Studio Instrument as VST, and can play notes and drum pads. I just can't get the control knobs to work. Installed ReaLearn, added the ReaLearn track to my Reaper Project, and tried mapping the 8 relative knobs to the 8 macros on the VST UI. Only way I could get it to even identify the knob wa on the MPK's "plugin" mode (not the DAW mode, which should be the one that worked). I mapped both ends, and the knob didn't manipulate the knob in the UI. I went into Edit on the mapping, and experimented with the different "source > character" and other settings. I got it to where I could see the Target > Value slider changing, but I simply could not get the VST UI to manipulate. I also could not get the Transport buttons (record, stop/play) to be recognized as a source in the ReaLearn mapping. Help???

[scottsknoll-arch]

Got it to work. On Reaper > Options > Preferences > Midi Input / Output, it's the "MIDIOUT2" device that controls the DAW, so you'll need to enable both MPK mini IV device for keys/pads to generate sound, and MIDIOUT2 with "enable input for control" left the "Source Channel" drop down as source channel. Then the Mini Plugin/DAW mode needs to be on DAW, then in Reaper Actions, Action List, you can select the action then add, then the transport control buttons (or any of the buttons/knobs) will pop into the shortcut field when you twiddle them. I think a lot of Reaper reboots, and keyboard unplugs help a long the way. I think the ReaLearn virtual instrument track with record enabled is necessary, even though there's no specific mappings I added. I tried taking it off and things stopped working, so I put it back.

[ronieri-a11y]

Hi
Did you get the controls of the Studio Instruments collection to work? The only thing I get moving is the modulation wheel.

[scottsknoll-arch]

yes, it works, and has been stable since I got it working. See my post above with more details, but basically I upgraded the Mini's firmware as the 1st thing I did, but then after that, I needed to delete the midi devices that get defined as they were from pre-firmware upgrade, and were buggy. after that, then the Plugin mode worked fine, all the knobs controlled the Studio Instrument Collection UI. I had to setup the MIDIOUT2 in Reaper to allow control, then in DAW mode, I had to define each knob what it did, and can control Reaper from the Mini... like pause/play/stop/record/undo, etc. I made the 8 knobs control the volume of tracks 1-8.

[Jazzycow11]

Yo, I also got one recently and have been slowly working out how to map all the functions to what they actually do on the controller. (e.g. with ReaLearn, I have succesfully mapped the Shift-inputs of the undo-record overdub buttons). Am currently working on setting all the others. Would love to perfectly map out all the functions.
Lemme know if anyone is interested and I'll certainly make an effort to share

[JonyR3G0]

Yes x2

[scottsknoll-arch]

Yes, it works. Fully mapping it out is up to what you want to setup. There's no Reaper specific mapping you can install like for Ableton (at least not that I'm aware of), so you have to map each and every button/knob to the Reaper Action you want. The key is to use MIDIIN2 or MIDIOUT2 from Reaper > Options > Preferences > Audio > Midi inputs/outputs: Enable for Input/Output/All/Control. Those are the separate virtual "midi devices" built in to the MPK Mini designed to send DAW (reaper) control signals. Other key is you have to use the PlugIn/DAW button on the MPK to switch back and forth between playing music with the MPK vs using MPK to control Reaper. It doesn't take that long, and allows you to set it up exactly how you want. Basically, make sure your MPK is set to the DAW, make sure in Reaper you've enabled MINIIN2/MINIOUT2 for Input and Control, then in Reaper > Actions > Show Action List, then select the action you want > add > then fiddle with the knob or button and Reaper should see it and save that physical action to the action list. Kenny Gioia has a good video showing how to do this in youtube: https://youtu.be/jE5lrzNsk-A?is=H6FfNOpEd-PR9A0f

You also don't have to map EVERYTHING all at once. Start with the basics... like Transport: Record, Stop, Play (buttons), and Track 1-8 volume (knobs)... add more over time to simplify frequent actions.

[ebbnflow98]

@Jazzycow11 can you explain how you got the shift functions to work with realearn? Thanks!

[Jazzycow11]

@ebbnflow98
so, First off you gotta make the Realearn fx inside of FX monitoring (so that it applies to all projects and not just the current track/project.

1. add the "vsti: helgobox - realearn" effect, and add 2 mapping groups (under main preset), one for when the shift key is active and inactive.
2. Click 'edit' for each mapping group and set both to "active when bank selected", set regular keys to bank 0 and the alternate function to bank 1
3. its a painful process, but take the time to map the buttons to their original functions in mapping group 0, and the shift functions in mapping group 1, and look up tutorials (basic functionality of the extension). tip: make sure they are set to 'button' in character on the left side.
4. Next, add a new mapping for shift key NOT IN any mapping group, make sure it is set to a button (momentary) in source, and in target set the following settings:
5. type to FX parameter: set value
6. set FX to 'this'
7. parameter to Particular, 1. Main p1: param 1
8. Value to 0%
9. in the lower section have source be min = 0, max = 1
10. Target min = 0%, max 1%

now you should be able to push the shift key and watch that 0% become 1%, and when looking at ALL the mappings, some will be greyed out and swap between being active and inactive. if it isn't working there's a good chance I missed some crucial step as I don't actually want to go back and recreate it just to learn the process again, and am just going off of what I understand from looking at it again.
Dev of realearn very much wants you to learn how every function works so that you can program it yourself instead of just making a tutorial that tells you how to do the thing you wanted to do. So i ended up just trying my best and making a mess of functions that works somehow.

Whole point of this is to have 2 categories of functions and only one can be active at a time, which you swap between with shift (which changes the selected category from 0 to 1, and back).

Below is an image which is INFINITELY easier to copy for steps 4 - 10, than understanding how the extension works lol. If you don't know alot about coding or computer shenanigans, but mind you it will be really hard to make your own changes if you don't know how it works (I barely remember and don't want to XD)

first time posting stuff on github, so hope this all works.

[ebbnflow98]

Thank you so much for writing this out! I got it working.

[Jazzycow11]

There's a special function where you can have a conditional set of actions that only work if a certain condition is met (in this case the shift key being pushed changes the actions of the original buttons). I'll make a full list later today when I've got some free time

…

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