So, my guitar tried to kill me...

[DDDorian]

I was playing today and felt a tingling sensation in my fret-hand pinkie. I thought maybe I'd been practicing too hard or something so I shook my hand to get the blood flowing, rested for a few minutes and began anew. The sensation soon spread to all of my fingers; then I suddenly realised: it wasn't my hand cramping up or falling asleep, my fucking guitar was electrocuting me, and managed to zap me pretty hard as I went to turn off the amp.

My guess is that it's due to the new cable as it's never happened before. However, should it be due to the amp I want to be able to know as it's still under warranty and I want to be able to replace it or get a refund if it's defective. How do I go about eliminating possible causes, and can I do so without plugging the amp into the outlet? I kinda value my internal organs. Thanks!

 

[Lozek]

Hmmm, are you in a position where you can easily take the amp back? If you're saying you got some from it when you went to turn it off, then it's probably the amp. Better safe than toasty I would say. Did you actually get a jolt from handling the amp itself when you went to switch it off? Were you still holding the guitar as well? Could possibly be an earthing problem with the amp, I would have thought it should have blown a fuse before trying to give you a bad hair day

If you're playing a passive guitar, you might want to check the bridge earth hasn't got disconnected as well, but that would be a secondary concern, because I don't think the amp should be supplying enough to be able to give you a jolt if it's all in working order.

 

[rogue]

i would expect it to be a fault in the elctronics of the guitar because the current would have to be in the strings to affect your left hand. so my guest is open up the cavity and check that nothings touching the bridge or anything. i wouldnt expect it to be caused by the amp or lead but i could be wrong

 

[Toshiro]

The guitar itself can't create enough voltage to shock you, AFAIK. More likey it's either the amp or the wiring in your house.

 

[DDDorian]

I'm starting to think this may be due to a faulty power board, but the earthing wire was quite loose; knowing my luck it was probably a combination of both. I'll have the amp looked at and replace the powerboard; worst-case scenario, I'm without a practice amp for a few weeks. Sure beats risking it and knocking up a batch of broiled geek for my flatmate to stumble over one morning.

 

[Black Watch]

Glad you were not seriously injured! Its true that amps do work with a huge amount of current, tube amps even more so. Grounding problems are a leading cause of leakage back into the instrument, and danger to the musician.

There are real cases of people being electrocuted by their amps, as in taken to the hospital or dead. Glad you were not one of them!

 

[David]

Take your amp off the carpet, and if it's close to many electrical fields, move it away. The same thing happens when I use my Fender super reverb amp on carpet, next to an outlet, and with a TV on. It shocked me bad enough to put blisters on my fingers.

 

[Elysian]

its a good idea to put a .001 microfarad capacitor in between your bridge ground and wherever its grounded to as well...

 

[Popsyche]

Make sure that the outlet is properly grounded, as well. Were you standing barefooted on the floor? There is nothing in a guitar that can shock you(Other than the price! Hee-Hee). You have a grounding problem where current is trying to pass between the electronics of you amp and the earth, using you as a wire. Remember, for the most part, one wire of that AC power plug is attached directly to your strings. It had better be the ground pin!

This could happen because of:

A reversed wall socket neutral. (Hot and neutral reversed.)

A polartity switch set the wrong way.

A significant problem with the amp.

Get a voltage meter and check between your guitar and a known ground source, like a water pipe.

I had this happen to me playing a gig at CBGB's in New York about 25 years ago. I was playing my guitar, and I went up to the mic to sing and a small lightining bolt shot between that mic and my lip. People said that the lights actually dimmed for a second!

 

[The Dark Wolf]

its a good idea to put a .001 microfarad capacitor in between your bridge ground and wherever its grounded to as well...

Won't always stop mild stuff, but will defintely stop anything that is painful or harmful.

http://www.stewmac.com/wiring101/resistors_capacitors.html

They seem to recommend running it with a 220k resistor, as well.

Of course, a wireless unit will work well, too. Part of why I always use my wireless live, since you never know the electrical conditions where you may play. A power conditionr on the amp circuit also is wise.

Of cours,e at home, the immediate issue is to fix what is causing the problem. Like Popsyche says, sounds liek a bad ground somewhere.

 

[Elysian]

Won't always stop mild stuff, but will defintely stop anything that is painful or harmful.

http://www.stewmac.com/wiring101/resistors_capacitors.html

They seem to recommend running it with a 220k resistor, as well.

yeah you're right i forgot about the resistor

 

[DSS3]

Man, that's nothing - my guitar wants to kill your momma.

 

[Mastodon]

Your house wiring can affect this?

 

[Naren]

Man, that's nothing - my guitar wants to kill your momma.

My guitar did kill your momma. Doing a life sentence in the state penitentiary right now as a matter of fact.

 

[Popsyche]

Your house wiring can affect this?

Absolutely! I use ancient amps with two prong plugs(no ground pin), and the prongs are the same size. You have a 50/50 chance of getting it right. That's why older amps have a polarity switch, which effectively reverses the prongs. On a standard plug, one prong is hot, one prong is neutral, and add the ground pin. If the outlet in your house is wired with the neutral and the hot reversed (A LOT more common than you would think), that hot prong could be connected directly to the strings and other metal bits, that should be connected to the neutral/ground.

 

[Nick1]

Funny story for anyone but me.

I was changing the tubes in my friends Peavey Rockmaster Preamp. The amp was plugged in but turned off. I also had my Carvin DC200 straped to me and at one split second I touched this metal piece that houses the 12AX7s and I had my left hand on my Carvins strings and HOLY SHIT DID I GET SHOCKED!!!!!!!!! My whole body was shakin like I was at rave!!!!!!

That sucked!

 

[Popsyche]

Funny story for anyone but me.

I was changing the tubes in my friends Peavey Rockmaster Preamp. The amp was plugged in but turned off. I also had my Carvin DC200 straped to me and at one split second I touched this metal piece that houses the 12AX7s and I had my left hand on my Carvins strings and HOLY SHIT DID I GET SHOCKED!!!!!!!!! My whole body was shakin like I was at rave!!!!!!

That sucked!

I have permanently erased my fingerprints in spots from shocks I have received. I have been working around electricity since I was 8 years old. As you now know , ALWAYS unplug stuff before you work on it!

 

[Mark. A]

Losing your fingerprints is pretty insane dude!

 

[metalfiend666]

Losing your fingerprints is pretty insane dude!

Makes him a good bank robber too.

 

[Popsyche]

Losing your fingerprints is pretty insane dude!

When I was young, I was kind of a nerdy knucklehead. Now I'm a much older knucklehead!