For more information about device selection, see this tutorial.
I’m using the below aliases for my testing. You will need to assign them to your actual physical ports.
You can learn more about aliases from this tutorial.
Each preset has 2 translators. The first translator of each preset processes any 3 byte MIDI message and the second one, only 2 byte MIDI messages. We use the second nibble of the first byte to determine the incoming MIDI channel an set the desired outgoing MIDI channel. Preset 1 converts incoming MIDI channel 1 (0) to outgoing MIDI channel 1 (0) for MIDI between the launchpad and the application. (actually no conversion here). Preset 3 does reverse conversion (again no conversion).
Presets 2 and 4 handle conversion from MIDI CH 1 to 2 and 2 to 1 respectively.
We don’t need conversion on 1 byte messages since they carry no channel information.
Then to allow System Exclusive and 1 byte messages to pass through, we set up the MIDI router as follows.
Since all of the translators have the ‘Swallow’ option set, the MIDI router is not involved in handling 2 and 3 byte messages. They are all handled by translators.