Hi.
Anyone have any experience retuning midi notes in Pd?
I'm working on a patch to re-map my midi-usb keyboard to play microtones (31-limit just intonation). Despite being somewhat of a novice, I was able to get this patch to work using oscillators/noise objects going through bp filters (borrowing heavily from another person to make it polyphonic. I can share that patch too if it would help). It's pretty cool, but ultimately, I'd like to play midi notes instead.

Everything I know about midi is very vague, so initially I just plugged the frequency number box into an ftom object. That's the state it's in now; just playing the nearest-pitched equal-tempered note.

But I did some research and now I have some questions: specifically, how do I send pitch-bend info along with the other note messages? Do I need a tuning dump first? Am I on the right track? Is this even possible?

The midi instrument I'm using for now is SimpleSynth, if that is important.

http://www.pdpatchrepo.info/hurleur/31limit_polysynth2_out.pd

Ahh, so I just discovered the bendout object. I will experiment more with this, but is it possible to use this on individual notes, or on multiple notes with different bend-values simultaneously?

You can do anything you want with that bendin/bendout info! That's the beauty of PD!

If you want to honor different bends for different notes, how does your downstream synth know what note to affect? You will need to think that thru.

I have been working on a simple guitar synthesizer, that works on six simultaneous channels of input, and honors pitch bend unique to each string. I know which notes the pitchbend applies to since the note & PB are on the same channel:
http://puredata.hurleur.com/sujet-9245-guitar-synth-honors-bendin-works-slide-whammy

You may find that example helpful, in showing the relationship between bendin values and your note values. You may be able to tweak the formula to honor your microtones.

Shawn

Thanks Shawn! Your patch was very helpful. I now have each voice on a separate channel with bendout data going through the correct channels simultaneously (I think that's all working).

However, I'm still having trouble getting bendout to work. I got it to work once or twice (not knowing what I was doing exactly) but now that I think I may have the input value right... it just doesn't do anything. (and therefore, I can't tell if the values are actually right). Here's the patch in it's current form. Any ideas?

http://www.pdpatchrepo.info/hurleur/31limit_polysynth2_out.pd

Ok, I answered my own question again; figured out the proper range of bendout and it works like a charm. I still need to tweak it as far as bend amount and other things go, but thank you for the help.

Sounds like your PBRs (pitch bend ranges) were out of sync. This needs to be set on both the 'sender' and 'receiver'. Most keyboard synths/patches default to a PBR of 2, some don't even let you change it. You sometimes have to read the manual pretty deep to find the PBR setting & how to change it.

I'd be interested in seeing your final patch! Please post when done. It looks like you are taking multi-channel input, adjusting the frequencies, then passing it on to the output, e.g., a downstream synth. If so, I'd love to plug my midi guitar into it!!!