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Midi preferences

Hi @haddad -

Just wondered… I see the commit for the disabling of microtonal MIDI settings was temporary(?). Is this coming back or do we need to explicitly set ports and channels in my patches going forward?

I was using the capability in the microtonal MIDI settings to increment the MIDI port for channels >16, >32… etc. Currently in 6.18 everything goes to port 0 unless explicitly set to something else.

If it’s not coming back as a global option I’ll make something to handle it in patches.

And am I correct that the logic for microtonal playback remains that globally a note’s MIDI channel is incremented by 1, 2, or 3 for 1/8, 1/4, 3/8 tones.



Dear Graham,

The reason i disabled these extra setting is that it was really faulty. It transposed notes one tone down or even much more than that. And regarding auto-bend, as expected, this doesn’t work with fast notes. So for the time being we are sticking to the default (old way) procedures of auto multichannel de-tune, which as you stated is incremental.
I intend to study a more general way to handle ALL microtuning using different ports this is on the todo list.
For the time being, and in order to get correct tones, one should follow the Tutorial 10 procedure for de-tuning (to be found in OM tutorial patches).

Sorry about this inconvenience.


Aha. Ok. No problem. Thanks Karim.

Is there a way to choose to disable the global MIDI channel mapper for microtones sometimes? In the short term I think I need to roll back to 6.16(?)

I was using two approaches dependent on what I was trying to achieve. One was to just use channels 1-4 for the microtonal routing and nothing else fancy. (no pitchbend, just routing).

The second approach was to use up to 16 channels of midi on each of up to 16 ports with the microtonal tools all completely turned off in OM settings and managed the pitch bends in patches like in tutorial 10. With OM6.18 it looks like the microtonal channel mapper is permanently on globally so that approach no longer can work. Even if you send a note to channel 1, if it is an 1/8, 1/4 or 3/8tone note, its channel number will get changed and sent to the wrong target.

Not a problem. I think I’ll roll back to 6.16 for now. I do love these tools! Thank you Karim.

All the best,


I was also using the MIDI channel number to port number mapper in 6.16 too, where assigning a note to MIDI channel 1 would route to channel 1 port 0 and assigning the note to the channel “256” would route to channel 16 port 15 etc.

I did work up an alternative pictured below but it doesn’t work as the MIDI channels get intercepted globally for microtonal notes.

Thanks Karim!

Hi Graham,

Yes I see. This can be of course restored. I will get on it ASAP as i finish some extra issues. Will keep you notified (send a patch).


Dear Graham,

If you need to access the ‘old’ extra midi settings in preferences, just drop this file in the init folder, restart Om and you’re done. You will find the old behavior (except the pitch bend issue).

Please don’t hesitate to tell me if something’s wrong.

midi-preferences.lisp (24.1 KB)


Amazing! Thank you so much Karim! Much appreciated!

Midi preferences (from OM 6.16) will be restored in the upcoming version (6.19) on request (They have been disabled, so we can figure out some issues).


Merci beaucoup, Karim!