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Microphone giving off small electric shocks

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As if I'm not having enough trouble with the whole psychology thing.....

Lined up for a little impro - just little runs, over the passagio. Got about 2 bars out and snap - a tiny little electric shock on my bottom lip. Now, I wasn't touching the mic, and would have been a little more than an inch away. It wasn't very strong - didn't trip out the safety switch on the house circuit board. Maybe it was just static, but it was big for a static shock. It was audible and showed up on the audacity track. What do you reckon - is it safe? One possibility is I had just had a big swig of coffee before I sang into the mic. Maybe the humidty on my breath was so high due to the coffee that electricity was able to jump across. I can still feel the tingle on my lip...

My mic is a lovely Rode M1 which is a little under two years old and has been well treated. I run this to a Behringer Xenyx502 mixer then into the laptop on the output cable to the mic jack on the laptop. There is power to the mixer. Normally I use a proper mic cable (XLR to XLR) but today I'm using a XLR to guitar input type cable because my friend borrowed my mic cable for a gig last night.

Far out... Earlier today I read the CVT book section on support and managed to get completely confused. Now my hardware is dolling out little shocks....

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Hi,

Is the guitar input lead 2 (TS cable) ring or 3 TRS (ie. balanced). Usually they are 2 for guitars and guitarists generally go 2 ring TS to DI box and XLR out from DI box to mixer. However you may be using a balanced xlr to trs cable.

With the Rode M1 being a dynamic it doesn't require phantom power. The (NEWER versions) Xenyx502 does have a +48V and i'm wondering two things (possibly 3)

1) however shouldn't happen ... +48V phantom is on (can you check the LED light, but I don't think the 502 has a LED!!) - but the Line in (below the xlr input) accepts TRS cable (3 ring) and shouldn't pass a voltage through the line in - it "may" and thus there is a static charge on the mic coil.

2) Grounding to earth on the Mixer - is it the usual three prong connector to wall (as per page 5 of the manual).

3) the odd one ... What were you wearing and are you moving about (i.e. Nylon)

Hope it helps

One Question I do have is, if you have plugged the T®S cable into the Line input --- is there an XLR cable in the line 1 xlr too ? - reaason I ask is that "if" there is an xlr inserted the +48 is active and "may" be jumping to the line in. But the two lines should never be used together.

i.e. Please remember that you can only use either the microphone or the line input of a channel at any one time. You can never use both simultaneously! (Page 6)

Upon doing further research, the newer 502's have phantom - but no switch to turn on / off, So I guess it's always on on the xlr input. SO check the previous comment.

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Hi Stew,

It's a balanced cable, XLr to trs. There is nothing in the XLR input jack.

Earth? what earth? I have no earth. I've been using this set up for over a year and haven't been shocked before - I guess perhaps I'm lucky!

I was wearing jeans and a cotton t shirt. But it is the dry season here at the moment and there is always quite a bit of static around.

I didn'tt know you had to earth your mixer. Should you do this at a gig too? Is that really just about static electricity? Wow.

thanks Stew. Maybe I'll go look at my manual....

SH

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Ron, I don't think so on this one... these are all standard members with numerous posts... and they are talking about mics? The spam usually have no more then about 1-2 posts... thanks for the heads up, please keep sending them my way... it seems to be slowing down a bit.

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Hi Stew,

It's a balanced cable, XLr to trs. There is nothing in the XLR input jack.

Earth? what earth? I have no earth. I've been using this set up for over a year and haven't been shocked before - I guess perhaps I'm lucky!

I was wearing jeans and a cotton t shirt. But it is the dry season here at the moment and there is always quite a bit of static around.

I didn'tt know you had to earth your mixer. Should you do this at a gig too? Is that really just about static electricity? Wow.

thanks Stew. Maybe I'll go look at my manual....

SH

Please, allow me to share my expertise. I might be a lazy singer, but I am also a master electrician (Texas Master Electrician License in my wallet.) And a master license from McKinney, Texas. A master/contractor license from Sherman, Texas. Etc, etc.

And now, I work as an office manager for an electric company that primarily does electrical work for swimming pools, spas, and outdoor kitchens, cabanas, and arbors.

And we must continually deal with what is called equi-potential grounding. The pool and spa and decking surrounding it, even the ground (if there is no decking, either sod or paving stones) must have the same grounding potential as the pool equipment, such as filter and cleaner pumps, as well as booster pumps for water features such as jets or cannons or scuppers. As well as the pool lights themselves, whether they be standard incandescents or LED lights that change color.

So, a ground wire has to be secured the belly steel before gunite in at least four locations, as well as four locations for the decking. Usually, we clamp on to sky bars sticking out of the pool shell. Not having that, we will leave four clamps on ground wire running through the deck area on its way to the pool equipment. If there is no concrete deck, we will run a ground wire all the way around the pool, 18 inches deep and 18 to 24 inches away from water. In some cities, we have to run a double loop.

For the same reason you are getting biz-whapped by your mic. The atmosphere can have different humidities within a few feet of each other. It's why you can walk across the carpet in winter time and touch the door knob or the plate screw on a light switch and get the crap knocked out of you. Parasitic (static) electricity abounds. So, you migh have a grounding issue that needs to be address. Perhaps the mic grounding is not secure enough.

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I might have to look at that grounding issue. Not sure how to make it better really. My mic is just on a stand with a heavy round metal base, on the linoleum floor, which is over wood boards held up by steel stumps (that is the construction of the building). Seems to make it better I need to somehow by pass the lino.... With what? How about a bit of electric fence tape (this is conductive) tied to the base of the mic stand and run out the door to the concrete slab on the patio?

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Hi,

I think the issue is likely the mic - trs cable and not your usual cable. Thoughts are it's possibly not shielded too well (i.e. shielded cable).

Once you go back to the xlr-xlr - issue may resolve it'self.

When I meant grounding - the mixer has a three prong round connector at the back, this goes to transformer which also (in Australia), has a 3 prong too that goes into the wall. Thus is grounded to earth house wiring.

As it's nothing that has happened for 2 yrs, the only thing changed is the cable. I think possibly there is a voltage in the line in (which there shouldn't) connector, but go back to your xlr-xlr cable and see if it continues. If so - we'll look elsewhere (i.e. earth grounding).

Stew

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