Static Electricity Problem with Digital Snake

B

Brian Wynn

Sophomore
Jan 12, 2011
108
0
0
Chicagoland
www.soundscoolliveaudio.com
The System consists of a Behringer X32, 2 Behringer S16 digital stage boxes, 150' of Horizon Duracat Cat5 cable.

Rewind back to a cold New Years eve night Dec. 31 2012. We had a double stack JBL VRX system powered by a pair of Crown XTI6002 power amps. Providing for one of our regular bands in a ballroom at a local hotel that we had just spent the week prior to that with a large christian group in the same room. The system we provided the week prior was almost the same system but with a analog Ramtech snake system. We loaded in around 5PM on NYE and I decided to try our new Behringer S16 stage boxes that we just received. This decision was made based on the current floor plan of the room it forced us to run the snake overhead and the Duracat cat5 cable would be much easier to fly than the 54 pair Ramtech. Everything went smooth as usual and we had our setup completed with in 45 minutes. Once FOH was set I decided that we should take a listen to the system before the band arrives. When I walked up to the desk I placed my hand on the lower right corner of the desk and ZAP I got shocked by static. Instantly I thought like a always do when my electronics get zapped "I wonder if that hurt the system"? It appeared all was functioning like normal. This scenario played out about 5 to 6 more time while waiting for the band to arrive. After the second time it happened I realized that each time I received a static shock from the desk I would hear a crackle-pop from the speaker system. This happened with all channels muted even the main output fader muted. I chalked it up as a non-issue. But then my stage hand walked across the carpeted stage and grabbed the guitar mic that was patched into the system and muted and then snap-crackle-pop my playback music stopped playing and then reconvened after the static shock was blasted through the speaker system. The best way I can describe the snap-crackle-pop sound is it sounded like a lot of clock jitter. Now for years I have accidentally given my gear a shock or two at a gig and never ever heard it through the speaker system. Now this is my first experience with a digital snake system and I'm wondering if this is a inherent issue with all digital snakes or is this a Behringer issue?

First thing this morning I made the call to Behringer and I was told that I needed to run a power conditioner on both the stage boxes and the desk and that will not happen. I think that is incorrect because a power conditioner shouldn't have anything to do with grounding a static charge in my opinion. Maybe I'm wrong. After that call I figured I would call Midas tech support in hopes that maybe they might have seen the same problem and since the companies are related now maybe they would shed some light on the subject. The answer I received from them was "well maybe you should have bought a Midas" literally thats what the guy said. Fun thing I told him I did have a Midas Pro1 and sold it once I took delivery of the X32. Now I'm wondering if maybe he was right.

FYI the FOH desk and the stage boxes where on different AC non gfci circuits in the room. Not sure if that would be a issue or not. Also there is no UPS backup involved.

If anyone has any thoughts please lets hear them. Until then Ill be in my shop with my X32 and a pile of balloons trying to replicate my problem.
 
Re: Static Electricity Problem with Digital Snake

Few questions. Did you test the outlets you plugged into? did you use a distro? have you tested your gear at your place on your outlets to see if the same thing happens?
 
Re: Static Electricity Problem with Digital Snake

The comment from Midas seems a bit off, and not really helpful.

A static shock can be death to any sensitive electronics. Usually the chassis is tied to ground, and any static shock given to the outside of the gear would travel through that connection to ground and not cause any issue. Now, if on one end of the gear, the ground connection isn't there, that static shock will find a place to travel until it finds ground. If that means traveling along the digital snake, you can be sure that will cause interruption in the signal. So my first guess is that there is a grounding issue of some sort. Even something like a neutral tied to ground away from the main panel can cause issues with static shocks.
 
Re: Static Electricity Problem with Digital Snake

Both good points.

I do not believe the non shielded cat5 is the issue. I shocked the console, and the microphones connected to the stage boxes. Not the cable itself.

I happen to be working in the same ballroom this coming week. So Im going to make sure all of the grounds are good on the receptacles that we used that night.

Ill post my finding's this coming week.
 
Re: Static Electricity Problem with Digital Snake

Static electricity can and is a big problem, Henry W. Ott in his big new book spends 40 pages on Electrostatic discharge. But static electricity is high voltage DC, it's not part of the AC power system. There are vendors that have many products for dealing with the problem. Often dis-charging with a high Ohm resistor works best.

Just do a search on "electrostatic discharge". Lots of products and information.
 
Re: Static Electricity Problem with Digital Snake

John Roberts said:
ESD damage is not a new concept.

Serious manufacturers test for it, and modern ICs have a lot of protection built in.

The vast majority of non-powr related component failures fixed by service are input or output circuits.

For an amusing instructional demo of ESD testing see...

Don't worry, it's just ESD! (Electrostatic Discharge) - YouTube

JR
Click to expand...

The impact from ESD isn't just damage. Many digital circuits can get put into unexpected states by the RF pulse that accompanies a discharge event. If you're lucky, it's just a transient state, but in some cases it could be a system reset, or a lockup requiring a system reset. The good news, though, is that modern EMC requirements have led to better protection against ESD as a side effect of meeting the more stringent emissions standards. And most analog circuitry won't be affected by ESD aside from the transient event.
 
Re: Static Electricity Problem with Digital Snake

Rob Timmerman said:
The impact from ESD isn't just damage. Many digital circuits can get put into unexpected states by the RF pulse that accompanies a discharge event. If you're lucky, it's just a transient state, but in some cases it could be a system reset, or a lockup requiring a system reset. The good news, though, is that modern EMC requirements have led to better protection against ESD as a side effect of meeting the more stringent emissions standards. And most analog circuitry won't be affected by ESD aside from the transient event.
Click to expand...
I recall an "interesting" event in a carpeted theater where upon touching a decidedly un-modern White 4700 EQ, which uses digital control of an analog circuit, I passed a big static shock which hurt like hell, then was accompanied by the monitors going into massive feedback.

After bringing the monitor sends down, it became apparent that the EQs had re-set to the previous state.
Save presets early and often when working in dry carpeted venue...
 
Re: Static Electricity Problem with Digital Snake

A digitally controlled product interpreting a static hit as a rouge input is pretty low on the list of worst case scenarios. Those of us old enough to recall the early days of digital microprocessors recall them dropping completely dead, and this was back when they cost $25 instead of $2.50. Many a slick expensive hifi product was totaled by simple static discharges.

Even with linear ICs surviving a static hit does not mean they didn't receive some subtle damage and may fail or degrade further in the future.

Factory workers are routinely required to wear static ground straps to not damage the work they touch.

JR
 
Re: Static Electricity Problem with Digital Snake

Dick Rees said:
ROTFLMAO!!!!!! That's one funny guy. Point taken.
Click to expand...
Slow learner, if you ask me......
But ya, pretty funny. By the 3rd time, you pretty well know what's gonna happen next.
Is that a conversion kit for a Weller soldering gun ? I know a DJ I could try it out on.........
 
Re: Static Electricity Problem with Digital Snake

Chris Hindle said:
Slow learner, if you ask me......
But ya, pretty funny. By the 3rd time, you pretty well know what's gonna happen next.
Is that a conversion kit for a Weller soldering gun ? I know a DJ I could try it out on.........
Click to expand...

I've always liked the idea of giving the operator a shock whenever the clipped one of my audio paths.... but alas the customer is always right and wouldn't appreciate my pursuit of linearity.

JR
 
Re: Static Electricity Problem with Digital Snake

Is the console in a plastic case or metal? Is the satge box in a plastic case or metal/ Do either or both have a fan in them?If so,this could be the cause of the static electricty. Years ago I wired a wood shop that had plastic pipe for the dust collector.The air moving across the plastic caused static build up.The manufacturer had a solution but I don't remember exactly what it was but it solved the problem.
 
Re: Static Electricity Problem with Digital Snake

Biggest problem I usually have with static electricity is just sitting down (or standing up) in that office chair that's usually parked in front of the console. A couple square feet of synthetic fibers being rubbed... zap!
 
Re: Static Electricity Problem with Digital Snake

Brian Wynn said:
The System consists of a Behringer X32, 2 Behringer S16 digital stage boxes, 150' of Horizon Duracat Cat5 cable.

Rewind back to a cold New Years eve night Dec. 31 2012. We had a double stack JBL VRX system powered by a pair of Crown XTI6002 power amps. Providing for one of our regular bands in a ballroom at a local hotel that we had just spent the week prior to that with a large christian group in the same room. The system we provided the week prior was almost the same system but with a analog Ramtech snake system. We loaded in around 5PM on NYE and I decided to try our new Behringer S16 stage boxes that we just received. This decision was made based on the current floor plan of the room it forced us to run the snake overhead and the Duracat cat5 cable would be much easier to fly than the 54 pair Ramtech. Everything went smooth as usual and we had our setup completed with in 45 minutes. Once FOH was set I decided that we should take a listen to the system before the band arrives. When I walked up to the desk I placed my hand on the lower right corner of the desk and ZAP I got shocked by static. Instantly I thought like a always do when my electronics get zapped "I wonder if that hurt the system"? It appeared all was functioning like normal. This scenario played out about 5 to 6 more time while waiting for the band to arrive. After the second time it happened I realized that each time I received a static shock from the desk I would hear a crackle-pop from the speaker system. This happened with all channels muted even the main output fader muted. I chalked it up as a non-issue. But then my stage hand walked across the carpeted stage and grabbed the guitar mic that was patched into the system and muted and then snap-crackle-pop my playback music stopped playing and then reconvened after the static shock was blasted through the speaker system. The best way I can describe the snap-crackle-pop sound is it sounded like a lot of clock jitter. Now for years I have accidentally given my gear a shock or two at a gig and never ever heard it through the speaker system. Now this is my first experience with a digital snake system and I'm wondering if this is a inherent issue with all digital snakes or is this a Behringer issue?

First thing this morning I made the call to Behringer and I was told that I needed to run a power conditioner on both the stage boxes and the desk and that will not happen. I think that is incorrect because a power conditioner shouldn't have anything to do with grounding a static charge in my opinion. Maybe I'm wrong. After that call I figured I would call Midas tech support in hopes that maybe they might have seen the same problem and since the companies are related now maybe they would shed some light on the subject. The answer I received from them was "well maybe you should have bought a Midas" literally thats what the guy said. Fun thing I told him I did have a Midas Pro1 and sold it once I took delivery of the X32. Now I'm wondering if maybe he was right.

FYI the FOH desk and the stage boxes where on different AC non gfci circuits in the room. Not sure if that would be a issue or not. Also there is no UPS backup involved.

If anyone has any thoughts please lets hear them. Until then Ill be in my shop with my X32 and a pile of balloons trying to replicate my problem.
Click to expand...

Ya'know. I actually don't think there was a certain fault mode at play here. I simply think this is how this particular gear reacts to static discharges!

I work some venues here where a combination of carpets and dry winter air builds up static like you wouldn't believe. I once shocked my thumb so hard it left blood on a Yamaha 01v96 :O

Best remedy I have found: Take off my shoes. Seems to build up a lesser charge. Also, try to touch something grounded other than the mixer first, after a walk across the venue.
 
Re: Static Electricity Problem with Digital Snake

kristianjohnsen said:
Ya'know. I actually don't think there was a certain fault mode at play here. I simply think this is how this particular gear reacts to static discharges!

I work some venues here where a combination of carpets and dry winter air builds up static like you wouldn't believe. I once shocked my thumb so hard it left blood on a Yamaha 01v96 :O

Best remedy I have found: Take off my shoes. Seems to build up a lesser charge. Also, try to touch something grounded other than the mixer first, after a walk across the venue.
Click to expand...

We had a similar problem at a church where I was tasked with upgrading their system. It was the worst in the winter. Anyone walking up (across nylon carpet) to the board and touching it got a good jolt of static discharge and the system would emit a loud pop. I tied all the pieces together with chassis ground wires (mixer, comp, line distro, CD burner, GraphiQ) and drained it off to a radiator pipe. It worked (works).

Static pops from the Pastors wireless transmitter were alleviated by anti-cling/anti-static spray on clothing worn under the vestments.
 
Randy Gartner said:
Is the console in a plastic case or metal? Is the satge box in a plastic case or metal/ Do either or both have a fan in them?If so,this could be the cause of the static electricty. Years ago I wired a wood shop that had plastic pipe for the dust collector.The air moving across the plastic caused static build up.The manufacturer had a solution but I don't remember exactly what it was but it solved the problem.
Click to expand...

Randy, the old solution used to be a bare grounded wire run through the pipes of a workshop dust collection system.
 
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