Somebody made a guitar 2 midi lv2 plugin

Not sure how useful it can be for Zynthian users. You’d have to be able to adjust the sample frequency at this stage of development. Could be interesting though.

I compiled it on a zynthian V4 with RPi4 and it… kinda works.

Zynthian does not have a mode that allows audio input and MIDI output. In theory the Audio + MIDI chain type should provide something like this but in practice, the MIDI output from the plugin is not routed. This may require some consideration because it is not a use case that we have previously considered and is not the purpose of Audio + MIDI. (That is to allow MIDI to control Audio plugins.)

The plugin has audio input and audio output but does not pass the input to the output so it mutes the audio in that chain.

Manually routing the MIDI output to a synth does work to some extent. There is significant latency that may be acceptable to some players but may prove intollerable for others. The note detection is probaby better than aubionotes and polyphony does work (which is an amazing technical achievement) but I found it challenging to tame it into something that I could produce consistently controllable music. Setting input level too high made lower notes inacurate but setting too low failed to trigger high notes. Polyphonic mode got a bit messy with more than a couple of notes playing.

It seems to use a single CPU core and doesn’t overload CPU even when playe polyphonically. It appears to use fairly consistent CPU of about 50% of one core.

This is a clever LV2 that almost works but given the challenges it faces, it may need more work before it can be used in a mainstream capacity.

So in summary, it doesn’t merit the effort required to integrate it with zynthian, yet!

Be aware that we already have a monophonic pitch to MIDI input module called aubionotes that can be enabled in the admin MIDI input menu and acts as a MIDI input device that can be enabled per chain. It hasn’t had a lot of attention so may be suboptimally configured. It only reaches down to abut B2 and is prone to mistriggering but it deserves more attention to see if we can tame it.

Should have realized there would be a strong probability of someone in the Zynthian community picking up on that.
Polyphony would actually not be crucial for me personally. To be honest, I need any excuse I can come up with to integrate my guitar into my workflow, so the poor thing isn’t gathering dust in the corner, and I don’t have to feel guilty about it.
So yes, aubionotes sounds really interesting, and I’ll sure be experimenting with it.

I have reported some issues on the github page and the author seems quite engaged but as previously mentioned, changes would be rquired to zynthian to make integrate it and I doubt we will rush to do that. I also observe it takes about 40% of jack CPU time which is quite high. By comparison, aubionotes uses about 3%.