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whannah
02-01-2018, 04:57 PM
This might not be a very exciting project, but it's solved a couple problems for me. I wanted to control a synthesizer from my organ, but I wanted a physical control for pitch bend and modulation, which the organ doesn't have. Also, I can't plug the organ into the synthesizer because the MIDI control change (CC) messages are sent to the synth when I don't want them to be. I can't disable the sending or receiving of MIDI on either instrument. Normally when I play a gig, I would need to bring a second keyboard to control the synth, which is a pain. So I built this little joystick box to give me a physical control and also filter the MIDI messages. My first gig with this setup is tonight and I'm pretty excited!

I used a Teensy 3.2

https://i.imgur.com/77iP4nd.jpg

https://i.imgur.com/F3uOH9s.jpg

https://i.imgur.com/DPbwkTU.jpg

https://i.imgur.com/UUeSll2.jpg

I'm also considering building another version of this that operates on audio signals, so you could add pitch bend to any keyboard, even vintage, electro-mechanical pianos. I would need a Teensy 3.5 for the FPU and the audio shield. And I would need to implement the phase vocoder technique in order to change the pitch of the signal, but I think I'm at a point where I could tackle this challenge. Besides the hardest part of any project seems to be drilling the holes in the right place!

oddson
02-01-2018, 05:48 PM
Die cast enclose, clean, solid looking perf-board. Gig-worthy build.


...the hardest part of any project seems to be drilling the holes in the right place! So true... looks like you did a great job on this one though.

I don't think a phase vocoder is available in the audio library and I don't think it's likely anytime soon.

(That's not a particularly informed opinion so perhaps someone more familiar with the algorithm can say if it's feasible with the current library framework on a T3.6 to produce a reasonably realistic pitch-shift within a reasonable latency. )

el_supremo
02-01-2018, 05:53 PM
Nice job on the packaging and good luck with the gig :)
Wouldn't it be easier to play if the pitch bend and modulation were foot controls (i.e. expression/swell pedals) rather than a joystick?

Pete

whannah
02-01-2018, 05:57 PM
Die cast enclose, clean, solid looking perf-board. Gig-worthy build.

Thanks!


So true... looks like you did a great job on this one though.

The hardest park was the 2 big hole sfor the Midi Jacks, I was a few millimeters off on the initial hole, so the don't line up very well. You can't really see that in the picture though. I still don't have a good strategy for figuring out where the holes should be drilled. The square-ish usb hole was tricky too. Had to dremel it out with the conical grinding bit.


I don't think a phase vocoder is available in the audio library and I don't think it's likely anytime soon.

Yea, I know, but I have the lofty goal of adding it to the library myself. I have an audio shield and a Teensy 3.5 that I put into another project, but I'm not using that project so I might re-purpose it for the pitch shifting idea, since it'll be a more interesting project.

whannah
02-01-2018, 05:58 PM
Nice job on the packaging and good luck with the gig :)
Wouldn't it be easier to play if the pitch bend and modulation were foot controls (i.e. expression/swell pedals) rather than a joystick?

Pete

Totally! I've thought about adding a jack to attach a foot pedal for this. I would need to practice using my foot for that. I've tried this before with a synth that could be programmed to do this, but it was much harder than I though.

oddson
02-01-2018, 07:07 PM
Foot pedals are fine for volume or pan or altering the cutoff of a filter but pitchbending notes would have to be limited to one direction with full up or down as the 'no bend' setting otherwise it's too hard to find and stick to the center pitch when you want to stay in tune.

Unless there's a middle-position-spring-return pedal out there somewhere already or your fabrication chops are much better than someone who admits they have trouble lining up wholes ;)

If I really wanted foot-controlled pitch bend I'd try a pair of load sensors to provide a ratio value that returns to unity when released and bend could be read from relative heal/toe pressures.

Edit - hmm that's what that dead bathroom scale could be used for.

el_supremo
02-01-2018, 07:50 PM
You're right. Pitch bend doesn't easily work with a foot pedal. The modulation might work out though.

Pete

whannah
02-04-2018, 06:42 PM
You're right. Pitch bend doesn't easily work with a foot pedal. The modulation might work out though.

Pete

Some sustain pedals that support "half-pedaling", like the Roland DP-10, are actually continuous. Once I set one up to do upward pitch bends on an Ultranova synth and it worked surprisingly well! There was definitely a learning curve though, so it would take some practice to make it sound good. If you had 3 of these, you could have pitch up, pitch down, and modulation. I think that would be the best way to control this stuff with your feet.

Robin
02-12-2018, 04:21 PM
Great project! I posted this to the project blog on hour home page. :)
https://www.pjrc.com/midi-joystick/

Stephpiano
07-12-2018, 02:05 PM
wow do you sale it?

Herman
02-25-2019, 09:55 AM
This is excactly what I have bveen looking for! The Teensy 3.2 looks like the perfect pitch stick. I would love to build one of these (or buy one from you if you are willing to make one for me). Would you mind sharing a list of all the parts you used as well info about any programming required? I'm not a programmer but could probably build it based on some kind of instructions.

Cheers,
Herman