Obtaining pressure from MIDI mapping Akai MPD18


Thanks to some great tutorials (hat tip to @raganmd and @watershed for your YouTube walkthroughs) I’ve managed to get my Akai MPD18 working as a MIDI input… Mostly. I have hit an obstacle in trying to obtain the pressure from the controller (distinct from the velocity).

For example; I hit button #1 and hold it, then the velocity shows the initial impact and the pressure I can modulate thereafter;

However, the pressure data seems to come in the format d4 xx 00, irrespective of which button I hold

Any suggestions as to how to get this data efficiently? I note another forum post (Midi Mapping Help) where judicious use of channel selection and MATH chops could achieve the goal, but ideally I’d like a clean way to obtain it from the midi in map CHOP at the outset.

I tried setting up another slider s2: d4 -- 00 to match the diagnostic from the MIDI mapper dialog, but this wasn’t successful.

Any ideas?

PS 1 the MPD18 has two pad modes, a ‘Full Level’ mode where any button push sends the max value (127) but the pressure is a distinct channel, and the default where velocity information is sent. Both modes can work, but the pressure value isn’t readily accessible.

PS 2 A related but distinct question: After saving the .tox file for the midi mapping as suggested in the tutorials, I can successfully load the configuration and enable it by setting the respective field in the device DAT in /local/midi. But despite giving it a name, I can’t see it in the midi mapper. Have I missed something, or is this expected behaviour?

Hi @groundhogstate,

From the manual of the MPD18 it looks like there are actually 3 modes:

Sounds like it currently is set to “Channel Aftertouch” but you would want “Poly Aftertouch”?

Regarding the Device. If you want to use it in a new project, drag the tox into the Devices List and it should become available as a Midi Map.


Yep, that’s the trick, classic RTFM… I wrote that guy off because the Akai website’s file downloads were blocked by all my browsers :wink:

For anyone else who finds their way here, interestingly the aftertouch comes in on a separate channel to the hit velocity so in principle both are usable; here’s me hitting a button, the top is constant during hold and the bottom is pressure sensitive.

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