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Title: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 05, 2017, 10:08:15 am
Hi,

After getting occasional drop-outs and popping with our X32 Core + S16 with an unshielded cable + ethercons, I recently replaced the cable with shielded heavy duty cat5e cable also with ethercons.

I understand this has solved the ESD issue for others, but it has made no difference for us. If anything, the problem is now worse. Last Sunday, for example, we experienced 2 loud pops.

I have double checked the snake cable. The drain wire is definitely attached to the ethercons and I have put an ampmeter across the connectors to confirm there is no break.

The X32, S16 and speakers are all on the same circuit. There is one output which goes to a simple powered splitter which is possibly on another circuit.
I have tested all the XLR cables and all test OK.
I relaid all XLR cables to increase there distance from power cables just as a precaution.

What other measures can I take to prevent the popping?

It does seem to be caused by ESD. We have had a long dry spell and the problem only seems to happen when there is a lot of movement of people in the room.

Any ideas or suggested solutions would be most welcome!
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Rob Spence on September 05, 2017, 10:11:09 am
Hi,

After getting occasional drop-outs and popping with our X32 Core + S16 with an unshielded cable + ethercon cable, I recently replaced the cable with shielded heavy duty cat5e cable also with ethercons.

I understand this has solved the ESD issue for others, but it has made no difference for us. If anything, the problem is now worse. Last Sunday, for example, we experienced 2 loud pops.

I have double checked the snake cable. The drain wire is definitely attached to the ethercons and I have put an ampmeter across the connectors to confirm there is no break.

The X32, S16 and speakers are all on the same circuit. There is one output which goes to a simple powered splitter which is possibly on another circuit.
I have tested all the XLR cables and all test OK.
I relaid all XLR cables to increase there distance from power cables just as a precaution.

What other measures can I take to prevent the popping?

It does seem to be caused by ESD. We have had a long dry spell and the problem only seems to happen when there is a lot of movement of people in the room.

Any ideas or suggested solutions would be most welcome!

What is this simple powered splitter?
Are you transformer isolated from it?



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Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Robert Lofgren on September 05, 2017, 10:35:10 am
Is everything properly grounded so the esd has somwhere to go?

You said drain wire. Are the actual wires surrounded by a shield and not just individually shielded?

Mechanical stress (bent cable, people walking on it,...) can cause the same symptoms.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 05, 2017, 11:20:50 am
Thanks for quick replies.

What is this simple powered splitter?
Are you transformer isolated from it?

The splitter takes video and audio components in and splits that for sending to two screens in other rooms. There is a balanced XLR to component audio adapter cable that goes from S16 out cable to this device.
It is not transformer isolated.

Is everything properly grounded so the esd has somwhere to go?

You said drain wire. Are the actual wires surrounded by a shield and not just individually shielded?

Mechanical stress (bent cable, people walking on it,...) can cause the same symptoms.

I wonder whether grounding is the issue. I had an electrical engineer check the grounding a few years ago, but perhaps it has deteriorated.

It is standard CAT5e shielding, i.e. there is a foil shield inside the cable jacket. The individual twisted pairs do not have their own shield but each pair has its own sheath which is what makes the cable heavy duty.

The new STP CAT5e cable is straight off the reel and AFAIK undamaged.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Bill McKelvey on September 05, 2017, 03:45:54 pm
Hi,

After getting occasional drop-outs and popping with our X32 Core + S16 with an unshielded cable + ethercons, I recently replaced the cable with shielded heavy duty cat5e cable also with ethercons.

I understand this has solved the ESD issue for others, but it has made no difference for us. If anything, the problem is now worse. Last Sunday, for example, we experienced 2 loud pops.

I have double checked the snake cable. The drain wire is definitely attached to the ethercons and I have put an ampmeter across the connectors to confirm there is no break.

The X32, S16 and speakers are all on the same circuit. There is one output which goes to a simple powered splitter which is possibly on another circuit.
I have tested all the XLR cables and all test OK.
I relaid all XLR cables to increase there distance from power cables just as a precaution.

What other measures can I take to prevent the popping?

It does seem to be caused by ESD. We have had a long dry spell and the problem only seems to happen when there is a lot of movement of people in the room.

Any ideas or suggested solutions would be most welcome!
Are any channels using phantom power? A poor connection will pop when moved/jiggled.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 05, 2017, 09:13:48 pm
Are any channels using phantom power? A poor connection will pop when moved/jiggled.

Yes, a few channels do use phantom power. I have tried moving/jiggling all connections but could not reproduce it. Also, the popping is much louder than I would expect from a bad connection, it is like a gunshot, so that is why I have been suspecting it must be an ESD.
 
But I will followup on your suggestion and test without those channels.

Edit:
I should also mention that there have been drop-outs as well as very loud pops. From the recording taken at the time, it looks to me like the X32 and S16 lost sync. From what I have read on the forums this also is a symptom of ESD.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Erik Jerde on September 05, 2017, 11:05:14 pm
Sounds like you made your own cable.  How did you test it?  Did you solder the drain wire to the shielded rj plug?  What kind of ends did you use (be brand and part specific here)?  Yournshield connection shouldn't rely on the ethercon connector.  You should be able to remove that and still have a solid path to ground via the drain wire.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: David Pedd on September 05, 2017, 11:11:23 pm
Your shield connection shouldn't rely on the ethercon connector.  You should be able to remove that and still have a solid path to ground via the drain wire.

Can you explain how that would work?
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Rob Spence on September 05, 2017, 11:23:49 pm
Can you explain how that would work?

Yes, there are metal clad RJ45 connectors specifically for shielded twisted pair.


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Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Erik Jerde on September 05, 2017, 11:24:44 pm
Can you explain how that would work?

You use shielded connectors.  It's like the plugs you are used to but they are wrapped with metal.  Remember, shielded connections existed in the data world long before ethercon and they still exist without it.  Ethercon exists primarily to protect the data connector.  It may provide some auxiliary grounding path but that isn't its primary purpose.  The shell doesn't make anywhere near a reliably good enough connection to the cable for that.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 06, 2017, 01:37:01 am
Sounds like you made your own cable.  How did you test it?  Did you solder the drain wire to the shielded rj plug?  What kind of ends did you use (be brand and part specific here)?  Yournshield connection shouldn't rely on the ethercon connector.  You should be able to remove that and still have a solid path to ground via the drain wire.

Yes I made the cable. No special testing other than checking for working network connection with it between my laptop and switch.
It was a generic RJ45 CAT6A shielded connector bought off eBay, so I can't give you specific part number, sorry, but it is definitely shielded with a metal outer case. My standard RJ45 shielded connectors were too small for the heavy duty cable (7.5mm diameter) which is why I went with CAT6A connectors.

The drain wire is wrapped around the metal strain relief that is part of the connector. As I was able to prove continuity between the ethercon ends with a multimeter, I concluded there must be a solid path between them via the drain wire and therefore a path to chassis ground. Am I missing something?

This is the cable I used
https://www.swamp.net.au/swamp-heavy-duty-cat5e-ethernet-network-patch-cable-100m-roll
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Scott Holtzman on September 06, 2017, 01:42:20 am
Yes I made the cable. No special testing other than checking for working network connection with it between my laptop and switch.
It was a generic RJ45 CAT6A shielded connector bought off eBay, so I can't give you specific part number, sorry, but it is definitely shielded with a metal outer case. My standard RJ45 shielded connectors were too small for the heavy duty cable (7.5mm diameter) which is why I went with CAT6A connectors.

The drain wire is wrapped around the metal strain relief that is part of the connector. As I was able to prove continuity between the ethercon ends with a multimeter, I concluded there must be a solid path between them via the drain wire and therefore a path to chassis ground. Am I missing something?

Yes, that connector is not attached properly.  You used the wrong connector for the cable and a non-standard attachment method for the connector.

Continuity is DC test, you are dealing with RF, high frequency AC.  Everything matters.   
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 06, 2017, 01:47:57 am
Yes, that connector is not attached properly.  You used the wrong connector for the cable and a non-standard attachment method for the connector.

Can you explain why this is the wrong connector and non-standard attachment method?
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Scott Holtzman on September 06, 2017, 02:19:30 am
Can you explain why this is the wrong connector and non-standard attachment method?

You said you used a connector connector designed for Cat 6 and wrapped the ground wire around the jacket.  Did I not understand what you wrote?

Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 06, 2017, 02:39:12 am
You said you used a connector connector designed for Cat 6 and wrapped the ground wire around the jacket.  Did I not understand what you wrote?

It is a CAT6A connector, but it is compatible with CAT5e.
The drain wire is not wrapped around the jacket. It is wrapped around the RJ45 strain relief. I think it is called a strain relief - it is metal part that extends from the RJ45 and is squeezed down onto the jacket to hold the RJ45 on more securely.

If that does not make sense, this video shows what I did with the drain wire. jump to about 3:10
https://www.youtube.com/watch?v=Xh7o99saQ4k
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark Dawson on September 06, 2017, 06:17:19 am
I would try two things: 

1:) Try an alternate brand of shielded cable and shielded connector.   We use a ftp cable here with zero issues.

2:) I would gently solder the drain wire to the lug at both ends of the cable, rather than just wrapping it.


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Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 06, 2017, 09:54:25 am
I would try two things: 

1:) Try an alternate brand of shielded cable and shielded connector.   We use a ftp cable here with zero issues.

2:) I would gently solder the drain wire to the lug at both ends of the cable, rather than just wrapping it.


Thanks for the suggestions. Maybe I can hire the Behringer approved Klark Teknik snake for a couple of weekends.

Could an ESD occur with an input or output XLR cable that also causes the X32 and S16 to lose sync?

As mentioned earlier, we do have an XLR out connected to a spltter using an XLR to component audio adaptor cable (Hosa).
There's also an XLR out connected to a video streaming camera using an XLR to 3.5mm adaptor cable.
AFAIK, both those adaptor cables are unshielded and do not have transformer isolation.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Rob Spence on September 06, 2017, 12:55:06 pm
Can you explain why this is the wrong connector and non-standard attachment method?

Cat6 connector with cat5e wire?

Maybe just buy the correct actual cable assembly? You spent thousands on the mixer and stage box. Don't cheap out on the rest of the data system.

I use a TMB Proplex with my GLD. Never a problem.

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Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Tim McCulloch on September 06, 2017, 12:58:33 pm
Thanks for the suggestions. Maybe I can hire the Behringer approved Klark Teknik snake for a couple of weekends.

Could an ESD occur with an input or output XLR cable that also causes the X32 and S16 to lose sync?

As mentioned earlier, we do have an XLR out connected to a spltter using an XLR to component audio adaptor cable (Hosa).
There's also an XLR out connected to a video streaming camera using an XLR to 3.5mm adaptor cable.
AFAIK, both those adaptor cables are unshielded and do not have transformer isolation.

Check to see if the camera has phantom power applied to the 3.5mm input.  Phantom will charge up any output coupling capacitors; when they reach discharge voltage they'll put a DC spike in the signal (and to the ground plane of the console).

You might do a search for the work Dan Mortensen and another engineer did with a BBQ lighter... remove the protective tip to expose the piezo element on a fuel-free lighter.  Spark up any exposed metal on the mixer or S16 and see what happens.  If this doesn't induce a drop out, the problem is not the CAT STP cable or its terminations...

My experience with UTP was that the pop was not like gunshot (it wasn't alarmingly loud, just irritating).  That level makes me think of a phantom power issue somewhere on the input side.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 06, 2017, 10:22:49 pm
Cat6 connector with cat5e wire?

Maybe just buy the correct actual cable assembly? You spent thousands on the mixer and stage box. Don't cheap out on the rest of the data system.

I don't believe there's an issue with using CAT6A connectors on CAT5e cable in our case.
https://www.platinumtools.com/sections/blog/datacom/can-a-cat6-connector-work-on-a-cat5e-cable/
The main issue mentioned there is whether the CAT5e is physically too small. Our cable is 7.5mm diameter with 24AWG conductors.

I don't believe I "cheaped out" on the CAT5e cable. It is sold specifically for this kind of application and cost considerably more than standard  STP CAT5e.
I could have spent more on the RJ45 shielded connectors, no doubt, but could not find shielded CAT5e connectors that fit this size cable. I went with the CAT6A connectors because they fitted perfectly.

I am not ruling out the possibility that the cable is faulty, but I doubt the type of RJ45 connector is the issue here.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 06, 2017, 10:34:25 pm
Check to see if the camera has phantom power applied to the 3.5mm input.  Phantom will charge up any output coupling capacitors; when they reach discharge voltage they'll put a DC spike in the signal (and to the ground plane of the console).

You might do a search for the work Dan Mortensen and another engineer did with a BBQ lighter... remove the protective tip to expose the piezo element on a fuel-free lighter.  Spark up any exposed metal on the mixer or S16 and see what happens.  If this doesn't induce a drop out, the problem is not the CAT STP cable or its terminations...

My experience with UTP was that the pop was not like gunshot (it wasn't alarmingly loud, just irritating).  That level makes me think of a phantom power issue somewhere on the input side.

Thanks for the suggestions.

The camera is on XLR out so there is no phantom power on that cable. But I will try removing all phantom power inputs. The popping and dropouts have only occurred when the room is full of people and the weather is dry, which means my opportunities to test changes are somewhat limited. Thankfully the church congregation has been patient with me chasing down the problem and have put up with me disabling parts of the system.

I have seen the Youtube videos uploaded by Brian Wynne. I was rather pleased to find someone else had experienced the problem and was able to recreate it. I had wondered about zapping our X32 and S16 the same way, but feel reluctant to put the church's gear at risk!
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Tim McCulloch on September 07, 2017, 11:55:51 am
Thanks for the suggestions.

The camera is on XLR out so there is no phantom power on that cable. But I will try removing all phantom power inputs. The popping and dropouts have only occurred when the room is full of people and the weather is dry, which means my opportunities to test changes are somewhat limited. Thankfully the church congregation has been patient with me chasing down the problem and have put up with me disabling parts of the system.

I have seen the Youtube videos uploaded by Brian Wynne. I was rather pleased to find someone else had experienced the problem and was able to recreate it. I had wondered about zapping our X32 and S16 the same way, but feel reluctant to put the church's gear at risk!

Brian is the other engineer I was thinking of (but couldn't remember his name).

You won't damage the church's mixer or S16 - look at how many times Brian and Dan tested their respective consoles without damage.

ESD is getting into the system somehow and I think it's prudent to start with known failure modes and eliminate or confirm them.  You can't test for what you don't know....
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mike Sokol on September 12, 2017, 08:03:42 am
Yes, a few channels do use phantom power. I have tried moving/jiggling all connections but could not reproduce it. Also, the popping is much louder than I would expect from a bad connection, it is like a gunshot, so that is why I have been suspecting it must be an ESD.

A phantom power XLR cable with an intermittent connection can sound like a gunshot. I once had a bass guitar active (phantom powered) DI that acted like that. One of the XLR wires inside the case was broken and would make/break contact if you tapped on the DI box. It would produce a pulse at full PA power, which was pretty scary and could have taken out some drivers if it kept happening.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Rob Spence on September 12, 2017, 03:40:09 pm
Thanks for the suggestions.

The camera is on XLR out so there is no phantom power on that cable. But I will try removing all phantom power inputs. The popping and dropouts have only occurred when the room is full of people and the weather is dry, which means my opportunities to test changes are somewhat limited. Thankfully the church congregation has been patient with me chasing down the problem and have put up with me disabling parts of the system.

I have seen the Youtube videos uploaded by Brian Wynne. I was rather pleased to find someone else had experienced the problem and was able to recreate it. I had wondered about zapping our X32 and S16 the same way, but feel reluctant to put the church's gear at risk!

Cameras often have phantom on THEIR input because they often use condenser mics.

That is what Tim is concerned about.

I always put an isolation transformer between my output and someone else's input.

Some mixers can be damaged by getting phantom applied to their outputs.



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Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 13, 2017, 09:47:09 am
A phantom power XLR cable with an intermittent connection can sound like a gunshot. I once had a bass guitar active (phantom powered) DI that acted like that. One of the XLR wires inside the case was broken and would make/break contact if you tapped on the DI box. It would produce a pulse at full PA power, which was pretty scary and could have taken out some drivers if it kept happening.

Thanks for sharing that experience. Following suggestions made by others, I disconnected all inputs with phantom power last Sunday. There were three drop-outs during the service where all sound was lost for less than a second - no loud popping this time. I believe it is random whether we have a loud pop or drop-out. We've  had both before. At this stage, I think the symptoms still point to ESD being the cause.

Cameras often have phantom on THEIR input because they often use condenser mics.

That is what Tim is concerned about.

I always put an isolation transformer between my output and someone else's input.

Some mixers can be damaged by getting phantom applied to their outputs.

Thanks for the clarification. Based on recommendations here, I bought an isolation transformer and have inserted that into the two outs that go to the camera and splitter.

If that makes no difference, then I plan to use the BBQ lighter test to see if I can recreate the problem.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark van Leeuwen on September 25, 2017, 09:42:39 am
Unfortunately, I still have not solved the problem.

I have inserted an isolation transformer in the two outputs. I made another CAT5e cable and following advice I read elsewhere folded the foil shield over the outside of the cable with the drain wire running under and over it then several times wrapped tightly around the RJ45 metal strain relief. This is in addition to earlier changes where I disconnected the speaker outputs and all phantom powered inputs.

The only connections that remain to the S16 are 2 dynamic mics and the 2 outputs protected with the isolation transformer.

Despite all that, we still had a few loud pops and drop-outs captured on both the X32 USB recording and the video stream.

I have now adapted a gas lighter and zapped the system in various places hundreds of times: S16, X32 core, XLR cable ends.

I managed to produce one pop and that was by zapping the ethercon connector on the CAT5e cable plugged into the S16 AES50 A port. Can anyone explain how that could happen?

I made one other test: I disconnected the CAT5e from the X32 and tested continuity by putting an ammeter between the disconnected ethercon and the X32 chassis. That proved continuity over the the CAT5e cable shielding to the S16 chassis, through the building wiring back the X32. I conclude from that test that the CAT5e shielding is grounded.

Any further suggestions would be appreciated.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Mark Dawson on September 27, 2018, 03:13:14 pm
Hi Mark,

I always solder the drain wire to the metal strain relief on the rg45.

Consider replacing the cable; we had an off the shelf shielded ethercon lead that was a bad apple.    No sign of damage along it, but from word go it misbehaved with the bang/dropout issue.




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Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Brian Jojade on September 27, 2018, 08:13:22 pm
How long is the cable that you are using here?  The AES signal on the X32 system is extraordinarily finicky.  It only takes you looking at it incorrectly for data drops to turn into huge noise.

Are you still using Cat 6A connectors on your cat 5e cable?  If so, that definitely could be a source of the problem.  Cat 6A cables are generally 16-20 gauge wires.  It may be making an unreliable connection when you are using much thinner wire in the cat5e cable.

Back when I first got the X32, I started with cheap unshielded cables.  Yeah, that was a mistake.  Then I went to my own shielded cable that I terminated myself. I terminate hundreds of cables a year, so I'm pretty familiar with putting on an RJ45.   Less problems, but still the occasional noise. 

Then, I found and bought Elite Core tactical Cat5e cables with the converta-shell option on them.  I have not had a single dropout since.  Yes, it was a bit more expensive than using bulk cable and terminating myself, but it works, and therefore worth every penny.
Title: Re: X32 + S16 popping with shielded cat5e cable and ethercon connectors
Post by: Tim Weaver on September 30, 2018, 09:32:25 am
Where did you run the cat5 cable? Is it on the floor subject to foot traffic?


I had a cheaper cable assembly that I made once that when it got stepped on it would pop. Evidently if the wire pairs inside the Cat5 shift around they can pop or drop out as well, no ESD involved.