This firmware version of the RK002 can be used to add controller data to velocity, modulation, aftertouch and pitch data.

RK-002/MOD firmware

Because the RK002 is able to add extra controller data to the note data, you can create velocity sensitivity to the Volca FM, or change parameters with regular keyboard controllers like the pitchbend or modwheel.

However, the controller number values are freely assignable so you can also use this firmware to add control to e.g. the Volca Kick, Roland Boutique’s, …, … We have made a few predefined templates on our site which you can use to add more performance possibilities to various gear.

Settings page with freely assignable CC Mappings

Or – the specific CC mappings for the:
KORG Volca Bass
KORG Volca Kick
KORG Volca Keys
Roland Boutique templates


As from firmware v50 it is possible to chain identical devices with the RK-002 to increase polyphony, we call it the PolyMUX parameter.

By default, the RK-002/MOD firmware modifies incoming MIDI data on MIDI channel 1. You can change this via the settings page.

If you set 1 extra PolyMUX channel, the RK-002 will duplicate MIDI messages from channel 1 to channel 2, with this exception that it will divide note messages across the two devices (you would need to split the RK-002 out to two identical devices).

If you would play 5 notes, division would be as follows:

midi channel 1 -> note 1
midi channel 2 -> note 2
midi channel 1 -> note 3
midi channel 2 -> note 4
midi channel 1 -> note 5

If you set 2 Polymux channels you need three devices. E.g. with a (3-voice polyphony-)volca Keys you would have 9-voice polyphony.

The extra PolyMux channel start at the RK-002 base channel +, so if the RK-002 is set at channel 1, the Polymux will send out at channel 2 and up.
If you set the RK-002 base channel to channel 15 and add 3 channels PolyMUX it wil wrap-around: You will receive messages on channel 15,16,1 and 2

as of version 58
Easy MIDI configuration! Start your synth and keep the key pressed on which you want to set the sample trigger basechannel. Plug the RK-002 and release the key within three seconds. Don’t press anything else or the RK-002 will not be reconfigured.

In order to do this, first the RK-002 must be unplugged/unpowered*.

  • Plug the RK-002 orange(MIDI out) end.
  • Set your keyboard/controller to the desired midi channel and octave you want to use with the RK-002.
  • Press the key on the keyboard/controller you want to set as basekey and keep it pressed.
  • Plug the RK-002 to the keyboard/controller.
  • Release the key on the keyboard/controller within three seconds.

After release, the midi channel and trigger basekey are set and saved to the RK-002 settings.

This configuration method applies for different firmware versions:

Firmware Action
Volca Sample set trigger basekey and midi channel
Modifier set midi channel
Arpeggiator set midi channel and command key

* Keep in mind that the RK-002 still runs a while on internal power after you have unplugged it. To drain the power from the RK-002, shorten the three middle pins on the black end with a piece of metal – the tip of a jack plug for example.