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Strings should be solidly bonded to ground. The entire guitar can be transformer isolated which is the technically proper and safe way to handle this other than fixing the real problem with the power distribution itself. The strings are bonded to reduce the effect of the strings acting as an antenna then coupling the EMI into the pickup system.

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I read the Mike Sokol article(s), watched his video, and then picked up a NCVT, Multimeter, and simple outlet tester. I tried all the outlets in the soon-to-be studio (older house) before we plugged anything in. Most of the outlets are simple Bootleg Ground, except of course for the one that's RPBG.

 

Time to call an electrician, and profusely thank HC.

 

Thank you.

 

 

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Yes, RPBG is especially heinous, and I'm constantly amazed at how many venue outlets are bad messed up (or potentially lethally messed up)... but the venue owners hold fast that there's "no problem" on their side of the connection. I guess it just goes with the territory and "plugger inner beware".

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Last night, while setting up for the show tonight, my son, our bassist, said he was getting a shock when his lips touched his mic.

 

He is playing a passive bass through an active EWI DI box, phantom powered by the mixer. We also usually stand on carpet, or rugs we bring if the venue does not have carpet. Last night, we were on our rugs and the weather has been cool and dry here.

 

I'm thinking he is getting static shocks from walking on the rugs with his big tennis shoes. I'm pretty sure the ground switch on the DI is enabled. However, I just set a reminder to check this when we get to the venue this afternoon.

 

I use a wireless guitar system and I sometimes, but not always, get a little shock when I step up to the mic. Only my lips are touching anything conductive when that happens. That is why I thing it's a static shock picked up from walking around on our rugs. In fact, if I just stand there after the first zap, I can repeatedly touch the mic without further zaps, until I start walking around again.

 

However, I want to be sure. We plan on replacing our home-built power boxes with some lightweight black boxes we found at Lowes.

 

So, my question is since my son is isolated with his DI, would faulty wiring still cause him to get a shock when he only touches the mic with his lips? If so, would lifting the ground fix that problem or only hide a different problem?

 

Thanks

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I am not an expert, but this is what I believe:

 

When his DI ground lift is not lifted, he is not isolated.

If you get a "snap" once per grounding, that is electrostatic discharge.

If you get a constant tingle, that is a mains shock of some kind

If you get a zap that throws you across the room, that is a mains shock for sure

If lifting the DI ground fixes something w.r.t. shocks, you have a problem with your wiring.

 

Here's something to try. Touch the microphone with your hand before touching it with your lips.

 

Wes

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Last night, while setting up for the show tonight, my son, our bassist, said he was getting a shock when his lips touched his mic.

 

He is playing a passive bass through an active EWI DI box, phantom powered by the mixer. We also usually stand on carpet, or rugs we bring if the venue does not have carpet. Last night, we were on our rugs and the weather has been cool and dry here.

 

I'm thinking he is getting static shocks from walking on the rugs with his big tennis shoes. I'm pretty sure the ground switch on the DI is enabled. However, I just set a reminder to check this when we get to the venue this afternoon.

 

I use a wireless guitar system and I sometimes, but not always, get a little shock when I step up to the mic. Only my lips are touching anything conductive when that happens. That is why I thing it's a static shock picked up from walking around on our rugs. In fact, if I just stand there after the first zap, I can repeatedly touch the mic without further zaps, until I start walking around again.

 

However, I want to be sure. We plan on replacing our home-built power boxes with some lightweight black boxes we found at Lowes.

 

So, my question is since my son is isolated with his DI, would faulty wiring still cause him to get a shock when he only touches the mic with his lips? If so, would lifting the ground fix that problem or only hide a different problem?

 

Thanks

 

The ground lift only isolates the grounds of two devices from each other. If each device is AC powered and has a grounded power cord, there are still paths to "earth" ground in the AC system. Ground lifts break a current path flowing from one device ground to the other via the cabling which is 'read' by the audio system as AC hum. In all cases when AC grounding is available it should be used. Never disable AC grounds with AC adapter plugs, clipping the ground pin, or other means.

 

It's hard to know for sure whether your son is getting static discharge shocks, or is being shocked by a power fault. It is rare but possible to get intermittent shocks via the latter. A voltmeter reading from the bass strings to the mic ball would show you whether there's any constant voltage potential present there.

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I read the Mike Sokol article(s), watched his video, and then picked up a NCVT, Multimeter, and simple outlet tester. I tried all the outlets in the soon-to-be studio (older house) before we plugged anything in. Most of the outlets are simple Bootleg Ground, except of course for the one that's RPBG.

 

Time to call an electrician, and profusely thank HC.

 

Thank you.

 

 

 

stay safe y'all !! )

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