midi mapcc experience?

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dvandok
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midi mapcc experience?

Post by dvandok »

I was trying to map the sustain pedal on my yamaha ydp-161 to another MIDI control signal to experimentally modulate a synthesizer setting.

In carla I tried adding the mapcc plugin (https://github.com/x42/midifilter.lv2/b ... rs/mapcc.c) and although it can see the sustain CC64 on the input, it won't change the selected output control. I think I may be misunderstanding something about what the plugin really does.

As another experiment I added a "Midi note to CC" to make C1 into a CC4 signal and route that into the mapcc plugin; I can see the input again but no output is changed.

There is remarkable little I could find on-line about these plugins, so I'm just sharing this experience here. Let me know if you have used this in some way!

(I'm on Debian 11 BTW, with pipewire.)
asbak
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Re: midi mapcc experience?

Post by asbak »

First you need to know what CC your hardware is sending.
For that you'll need some kind of MIDI monitor program (Drumstick or whatever) that will tell you what CC traffic, if any, your hardware is generating.

Once you have that confirmed you need to assign those controller values to your plugin in Carla. You don't need to transform MIDI CC to achieve that, most plugins in Carla display their own parameter settings page which can be assigned to whatever MIDI CC message you want.


1) Read the CC values generated by your hardware with kmidimon, drumstick or whatever. Now you know which messages your hw is generating.

2) Optional step - Reprogram the hardware to generate different CC values if needed, or if possible. For example, I remapped the pots on my AN1X keyboard to send the CC values I require, not whatever the previous owner or factory programmed.

3) In carla, load a plugin like Obxd (as an example). Click on the spanner. Click on the parameters tab. Click on the "... " next to "unmapped" for the parameter you want to control. Assign or learn the appropriate CC.

4) Profit.
Some Focal / 20.04 audio packages and resources https://midistudio.groups.io/g/linuxaudio
dvandok
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Re: midi mapcc experience?

Post by dvandok »

Thanks for the reply! In the mean time, I found out what my misunderstanding was with the mapcc settings.

In the parameters tab, there is a button of the right to the input CC field that says "map...". In fact, there is such a button for every parameter in every plugin. When I clicked on that button to "learn MIDI" and I pressed the sustain pedal, it would map CC64 (which is sustain, not surprisingly) to the input parameter. And I could see the value go up and down as I pressed the sustain pedal (which has something like an 8 step gradient on my piano).

As is obvious to anyone who worked with these plugins before, this 'mapping' of parameters to midi signals is a useful way to add another layer of indirection where you can let a MIDI control direct the setting of a plugin parameter. But for the mapcc plugin this is probably not that useful :D

I simply needed to unmap the parameter and stick a fixed value of 64 into the field, and when I stuck the value 1 in the output CC and routed my midi through this plugin to the surge synth, my sustain pedal now acted as a modulation wheel. Very useful for those presets that actually map the modwheel to something interesting and certainly a lot of fun.

With the additional plugin key-to-CC I mapped the lowest keys on the keyboard to create additional CC commands and that certainly worked, but piano keys are a poor substitute for sliders and wheels. I'm thinking of getting a midi control keyboard for more knobs to turn.

Cheers and a shoutout to Robin Gareus for an awesome set of plugins!
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