MidiStick V2.0: Next gen tesla coil interrupter

[AeraCura_]

...designing a little case to go around the stick.

I was working on something similar while I wait for my stick to arrive, can't wait!

[Mads Barnkob]

Maybe a custom USB hub with enough distance between ports to allow for the height of the optical transmitter... Maybe there is some crypto-mining hubs from when USB stick miners was a thing that has some extra clearance...

[octopus1]

Once I get mine I’ll try and design a low profile case for 3D printing, it would be difficult to design a case that works for both types of fiber optic transmitters though. It would be cool to make it look like any other usb stick!

[TMaxElectronics]

Awesome ideas
I have started working on a small case which would allow them to fit side by side back when I started the project, but never finished it.

The width of the stick should be small enough to fit side by side on most usb hubs, so a case that gets glued on from the top and bottom would solve the issue, but that would then mean gluing something on which I usually try to avoid.
I haven't really looked into printing clips like those used in cheap enclosures, but since they seem to be maybe a few mm wide, they might still fit.
But the biggest issue I guess will be keeping the pins, and aux connector accessible.

Looking forward to more ideas

[TMaxElectronics]

Just another small update:

I have gotten some of the old openmoko usb pids, so the thing is now properly usb compatible (though I think I have to pay fees if I actually want to be allowed to put the logo on).
Apart from that I have also been continuously working on bugfixes with VMS, but don't really get to release anything because I have found another bug to fix by the time I have drafted the release text

There are now also more circ parameters that can be used for circular modulation curves (no low pass on that yet though) and the drum map is taking shape; the effects of non-acoustic percussion instruments, that can be modeled with white noise are pretty much perfect and the drums are starting to sound decent as well with the help of multiple voices per effect. Bummer that I can only test my coil in my basement right now

[octopus1]

Hello all!

I just received my midi stick in the mail and wanted to give it a quick test. I have it all setup and the blue signal light lights up for each note played but I am not getting any output on the transmitter LED. I tested the E96E transmitter before hand and it worked fine. I also removed the HFBR Resistor as I thought this might have been the problem. Any bell would be much appreciated, from what I can tell so far this is a amazing little stick!

[TMaxElectronics]

Did you follow the quick start guide and create&select the configuration for your coil?
Without that it won't do anything to prevent damaging the coil it is connected to

[octopus1]

I have it set to the default setting for the coil (100us max on time, 10% duty cycle, 30us note hold off) and LED3 which I have set to output on blinks blue with notes but still no output on the transmitter. For E96E types the LED Connects to the middle top pins right?

[TMaxElectronics]

just a little bit of an update:

I added some more features to the VMS and it can now play multiple notes from a single note on even, which can make it sound like a classic 80s synth, and did some more bug-fixing too. I also recorded some little tutorial videos on how to get started with the MidiStick and how to get the best sound of it, which I'll post on youtube in the Coming days. I think I'll make them unlisted though since they aren't of any importance to my normal audience so I'll just embed them in the github wiki page.

I still can't go to the HV lab and running the coil in the basement is not an option either since the place I made the other videos has now returned to being the paper waste storage which I'd rather not light on fire if I'm honest
But I made a post on my website that has a bunch of captured audio examples on it. Not with a coil but just recording the output from the interrupter directly: https://tmax-electronics.de/projects/midistick-news/midistick-audio-only-demos/

Oh and probably the biggest news: I finally got around to opening a shop on my website so if you want a MidiStick you can now buy one directly https://tmax-electronics.de/product/midistick-v1-2/

[TMaxElectronics]

Finally some updates again

I released V1.2 of the firmware and the configurator: https://github.com/TMaxElectronics/MidiStick_Firmware/releases/tag/V1.2
The changelog is over there for those interested.

I am also starting to get the VMS maps dialed in to where they sound really good, so I recommend giving the new one a try (it even uses some new features )

There are however also bad news... As you might recall octopus had issues with his midistick a long time ago and unfortunately they haven't all been solved. The reason seems to be some incompatibility between the USB library I use and macOS. LibUSB had some issues a while back that were fixed recently, but unfortunately it looks like the development of the java port ended in 2018.
Now that the new release is out I have started experimenting with different libraries and will eventually port over the entire configurator to the most promising one I find.
until then there is no support for using the midistick on macOS

As a side note:
does anybody know how the copyright system deals with midi files? I've seen Max talk about putting up some example files (or actually doing that? not sure at the moment...) and was thinking about doing the same.
Nothing especially prepared but just a few of the midis I use for testing and that I know work well.
Is it even legal to share those on forums or github?

[Mads Barnkob]

I guess its very grey zone, some forums posts suggests that its running wild because no publishers are involved with MIDI files, only the artists directly. So there is no money force behind chasing down a market with almost zero market value...

The long answer: http://www.higgs.com/archive/articles/keyboard/june-1993/

[TMaxElectronics]

Hmm interesting reason for nobody caring about the files being shared...
But I guess since others are doing it here too I'll just upload some demo files once I get around to it.

Oh and I finally got around to adding a "normal" interrupter mode and a live performance window:


The transient mode allows for playing single tones and also has a burst mode.
The idea behind the show control window is to always have a window on hand that has an E-Stop and (when midi mode is selected) faders for the master and individual coil volume to allow for better adjustability while a file is playing. At the moment it isn't possible to adjust the volume of a track that is playing on two coils for each coil separately, with any power differences between the coils only being scaled out by the maximum OT of that coil. Having a fader for each individual coil could allow for quick adjustment of any mismatches.
I should have this update out in a week or so

Also if you have a stick and had time to test the latest update I'd love to see some videos of it
It looks like its a long time until I get the chance to run my coil again or build a smaller one.

[TMaxElectronics]

And now there are even more upcoming features and this one is a big one I think
I added the ability to act as a NetSID server and play .sid files (the Commodore 64 sound files) through an external player like Acid64.
The songs in those files are made to sound good on only three voices and hence are suited to playing through a tesla coil a whole lot more than most midi files are (at least without any modifications).

Here is a short demo... just so annoying that I still can't get to the lab and play it on a real coil:

[TMaxElectronics]

There are even more big changes coming

I finally managed to get the usb for macOS working again, so the next version will work on that again (finally ).
I also added master volume controls to the midi and sid show modes, so it's easier to reduce the volume while a track is playing. That way it feels less like driving without a steering wheel (or would it be the brake?) in those modes

The show control window can also stay on top of other windows so the volume slider is always in reach if things go south

[Mads Barnkob]

Great updates and exciting new features. The SID implementation sounds really cool, I am looking forward to hear that endless pitchbend on a Tesla coil, will it produce it faithfully?

[TMaxElectronics]

will it produce it faithfully?

Absolutely
The video's audio is recorded straight from the output of a stick and these sort of effects sound great on coils too.
The video I uploaded on new year's day this year is SID instead of midi too (but with the UD3's built in synth), thats sounds great in my opinion :

[TMaxElectronics]

Ok this entire not having a coil that I could run thing was starting to get on my nerves... so I decided to use my big bridge with my old (small) secondary coil and FINALLY get some demo videos.

Monty on the run and popcorn 101 is played in SID mode, the other two are midis:

[TMaxElectronics]

I have one more, this time actually recorded with a proper camera and microphone (even with shielding )
This time its all old chiptunes played in SID mode. Sound pretty cool imo :

At 400us on time even the bassy notes come through well

[Uspring]

A very impressive accomplishment! It's been a long way from the pong game arcade style music.
So when will you implement Dolby surround? 

[TMaxElectronics]

Thanks

So when will you implement Dolby surround?

Well there is stereo position mapping of coils

And on a side note: There are even more added features in the next release now.
With some low level uC magic I got the voices producing two pulses each. Both at the same frequency, but with a phase setting that can be used to create effects like a phaser.
It sound absolutely awesome through speakers, but I haven't tested it on a coil yet since I had to free up the basement again for now

I know that I said I'd have the version ready by last week, but I'll stop adding new stuff to it now and just focus on getting the update with the SID and TR mode out.
If I don't discover any terrible bugs I should have it ready... soon