[LAU] LV2 plugin that controls other plugins?

[Christopher Arndt]

Am 11.03.21 um 16:54 schrieb Mark Raynsford:
> Is there a (free, open source) plugin out there that allows for
> controlling the parameters of a plugin from another plugin? I
> realize that question's a bit nebulous. I'd like to, for example, 
> have a plugin that exposes a MIDI input. When a NOTE ON is received on
> that input, it sets the value of a parameter in a different plugin
> to a given value, and when a corresponding NOTE OFF is received,
> it sets the value back to something else.


I see two avenues here:

a) CV ports and signals
b) LV2 atom Patch set messages

With a) your plugin would have a CV ouput, whose signal depends on some
input (audio, MIDI or CV), and is connected to a CV control input port
of another plugin. Of course that means you can only control parameters,
for which the receiving plugin has CV inputs.

For the MIDI -> CV conversion you might not actually need to write your
own plugin. There are some MIDI-to-CV LV2 plugins in existence already.

See this list [1] for a selection ([2] might contain what you need).

b) Relies on the host actually forwarding atom messages between plugins.
I'm not sure how many and whoch ones do that, but I believe at least
Ingen and synthpod do.

You might be able to do the MIDI to atom message conversion with
Moony.lv2 [3].


Hth, Chris

[1] https://linuxmusicians.com/viewtopic.php?t=20701
[2] https://github.com/moddevices/mod-cv-plugins
[3] https://open-music-kontrollers.ch/lv2/moony/#