I'm thinking of buying a Cantini MIDI violin. The person from electricviolinshop.com says I would need to hook it up to a MIDI-controller/synth like the Roland GR-55 and then into my computer to get useable MIDI data.

Has anyone done anything like this? I want to know how the data would be detected in Pure Data. Would each string have its own channel # when using [notein]?

Also, [notein]'s velocity value is the amplitude, right? So it would change depending on the strength of the string's vibration, right?

Edited the title to make it potentially more universal... maybe I'll get an answer this way. ^^;

@s.elliot.perez
It seems to have a 13 pin midi connector.... but maybe it's not midi data.
There is a miniscule amount of information here...... http://www.cantinielectricviolins.com/2/technical_support_2950879.html
There is an interface here...... https://www.roland.com/us/products/gi-20/ and at least that unit could be necessary to get midi data into Pd.

I think you will need to read this......
https://www.researchgate.net/publication/255569994_ADAPTING_POLYPHONIC_PICKUP_TECHNOLOGY_FOR_SPATIAL_MUSIC_PERFORMANCE
.... and it will probably tell you what you need to know.

If you just want a loud violin you could try an Accusound Omni microphone. That is what I use with the Balanescu Quartet, and we have done pop and even heavy metal gigs.

Or you could try deconvolution with a piezo pickup...... https://forum.pdpatchrepo.info/topic/7778/deconvolution-for-rt-spectral-stamping-of-violin

But if you want some other synthesis then that violin could be a good solution.
David.
(P.....S...... It looks like you can also buy the pickup separately.......)

@whale-av Hey, sorry I never replied- I just saw your reply now after I bought the instrument. I ended up getting the BOSS GP-10 as a MIDI interface for the instrument. I knew the GR-55, SY-300 and SY-1000 would work as well, but didn't know about the GI-20. Maybe it would've been more affordable...

Here are my notes. Happy to hear anyone else's experiences or ideas about how I can get the most out of this device:

1)The instrument has screws on the back that you can turn to increase/decrease the sensitivity of each string. I've adjusted these a bit with dealing with the problems mentioned below in observation 9)

2)The GP-10 also has some settings for more or less dynamic contrast. I've experimented with setting these differently, though setting "Dynamics" to 1 and "Play Feel" to FEEL 1 seems to be the best. Changing these doesn't seem to do anything for the problem in 9).

3)I have the GP-10 set to MONO mode, rather than poly mode so that each string outputs to a separate MIDI channel.

4. The output to separate channels works well if you do clear attacks with the bow (or use pizzicato of course). The attacks need to be clear whenever you switch to a different string. Raising the sensitivity (cf. 5)) allows you to have clear attacks that are still somewhat quiet.

5. As long as a note is sustained, you get continuously updated bend values, which can be combined with the original noteOn value to get exact pitches and perform glissandi. I combine the two values in Pure Data with math objects. noteplusbend.pd

6. The MIDI velocity value does not update continuously, but in PD I can use the velocity's value as a switch to allow the Audio-in (which also comes in through the GP-10's USB) to control the volume of the MIDI-activated note via [spigot].

7. Because attacks with the bow need to be clear, if you fade in a note very gradually with the bow, it won't be detected as MIDI.

8. By combining 6) and 7) I can construct patches in Pure Data so that a certain sound will play and be controlled purely by the Audio-input and that others will be activated by MIDI+Audio-Input. Eg. I can fade in a sound, crescendo with an up-bow and then attack crisply on the down-bow to activate other sounds.

9. There are some issues with stable pitch detection when playing double-stops (diads) on two neighboring strings. It seems when doing so that there's some interference. However, for some reason, playing smaller intervals (major 3rds or lower) seems to work better than larger intervals. And avoiding open strings helps as well.

10. The pitch detection of 9) could be ameliorated by removing the bend value from the equation, but of course glissandi/microtonality would be lost as a result.

11. The E string (the highest one) gives the quietest, least consistent output. Pitch detection suddenly falls off after the first octave.