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koolksmart

Tue Apr 16 2013, 09:34PM

Registered Member #5300 Joined: Thu Jun 14 2012, 12:00AM
Location: California
Posts: 31

So I've been trying to get the FlexiBrute Polyphonic MIDI Interrupter working with my MicroBrute DRSSTC when the MIDI output is from my computer. My setup works just fine when I output from a MIDI keyboard, but whenever I try from my computer, as soon as the first note is sent, I get a single, sustained spark that keeps running to my grounding rod.

A bit about my setup (I'll upload pictures when I get a chance to put everything together again soon): I've got the secondary and toroid with a breakout point pointed towards a 12 gauge wire which is grounded via the ground terminal on the control board itself. The control board is exposed but far enough away from the coil that I haven't had any problems thus far when using a keyboard or just the standard controller.

I'm using the included coax cable to the Flexibrute controller which is run from a 9V battery about ten feet away. The board is exposed as well, but it hasn't run into issues when running from just the keyboard. I am using the following USB-MIDI adapter:

I make sure to leave space as well between my computer and the interrupter.

The programs I've tried using are Anvil Studio 2012 and PC73 Virtual Piano Keyboard.

...any thoughts?

Thanks!

Physics Junkie

Tue Apr 16 2013, 09:52PM

Registered Member #7267 Joined: Tue Oct 16 2012, 12:16AM
Location: Detroit, Michigan
Posts: 407

I have the same problem when running from those pesky USB devices. The solution is to improve grounding and/or move farther away from the coil. Those USB devices as well as laptops are more sensitive to the rf than your keyboard (I think). Get a longer cable.

If im understanding you, you're letting the sparks strike a 12 gauge cable thats connected to your circuit board? All strike targets should be connected to the bottom of the secondary

HV Enthusiast

Wed Apr 17 2013, 12:41AM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

Koolksmart,

Please download our latest revision of the flexibrute MIDI interrupter manual. There is an error on the RCA connector and the connector must be reversed, or placed on the bottom of the board.

This is corrected in the new revisions of the board. And this issue is only with the RCA connector. The fiber optics are fine.

Be sure to check out our Facebook page. We just posted a REALLY COOL video of one of our customers who connected a Laser Harp to their microBrute DRSSTC. Really cool stuff!

koolksmart

Wed Apr 17 2013, 03:47AM

Registered Member #5300 Joined: Thu Jun 14 2012, 12:00AM
Location: California
Posts: 31

EasternVoltageResearch wrote ...

There is an error on the RCA connector and the connector must be reversed, or placed on the bottom of the board.

I am using a BNC-RCA adapted to output through the BNC connector. Hopefully that changes something.

Thanks!

HV Enthusiast

Wed Apr 17 2013, 01:52PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

The BNC is fine.
Thanks

koolksmart

Wed Apr 17 2013, 02:18PM

Registered Member #5300 Joined: Thu Jun 14 2012, 12:00AM
Location: California
Posts: 31

Physics Junkie wrote ...

I have the same problem when running from those pesky USB devices. The solution is to improve grounding and/or move farther away from the coil. Those USB devices as well as laptops are more sensitive to the rf than your keyboard (I think). Get a longer cable.

If im understanding you, you're letting the sparks strike a 12 gauge cable thats connected to your circuit board? All strike targets should be connected to the bottom of the secondary

Which cable(s) should be longer? And how could I improve grounding?

I'm trying to upload photos of my setup but the website, imgur, and photobucket won't let me. I'll keep plugging away.

Thanks!

Physics Junkie

Wed Apr 17 2013, 03:46PM

Registered Member #7267 Joined: Tue Oct 16 2012, 12:16AM
Location: Detroit, Michigan
Posts: 407

Longer bnc/rca (which ever is your cable running between the tesla coil and MIDI circuit). Try moving all sensitive electronics (laptop-USB device-midi controller) much further away. Those USB devices are very sensitive and I wouldn't be surprised if the proximity to the tesla coil is the issue. Even my little sstc can cause the MIDI device to hang up notes until I move it at least +15 feet away. Even more distance is required for bigger drsstc

koolksmart

Fri Apr 19 2013, 03:40AM

Registered Member #5300 Joined: Thu Jun 14 2012, 12:00AM
Location: California
Posts: 31

Physics Junkie wrote ...

Even my little sstc can cause the MIDI device to hang up notes until I move it at least +15 feet away. Even more distance is required for bigger drsstc

I just tested with 34 feet of cabling--I can't even see the coil and can barely hear it from how far away I am, and I still got a hung note...I have no idea where to go from here.

HV Enthusiast

Fri Apr 19 2013, 02:29PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

Longer cables could be worse. These could act as antennas and the longer they are, the more efficient they have at picking up noise.

And you describe what you mean by "hung note?"

Steve Conner

Fri Apr 19 2013, 03:10PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Hung note usually means that the MIDI Note-Off message got lost, so the note carries on for ever. If the synth doesn't have an All Notes Off button, you have to bash away on the keyboard until you send another Note-Off for the note that got stuck.

That's what I always did in my home studio MIDI setup anyway.

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