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Since I bought a multipack of cheap patch cables for use between pedals I've been getting some small electric shocks from the guitar strings and pedals themselves, as well as no sound from the amp.

The first time I just replaced a cable through process of elimination and figured it was a faulty soldering job in it... now after the 3rd cable to have caused it I checked the continuity between tips and sleeves of all three cables and all seem OK so made me wonder why replacing these cables made any difference.

One thing I did notice is that the jacks on these cables are 2mm to 3mm longer than those on any other brand of cable I own and thus the sleeve is pushed further into the pedal. Could it be that the sleeve of the jack is coming into contact with the tip's contact in the socket in the pedal? This would be bridging ground and live and lead to no sound and a shock, wouldn't it? In the attached image the black cable is the offending cheap item versus another of my 'working' cables.

I'm just hoping someone can confirm that could cause the problem and whether anyone else has experierenced it before I make a journey to the shop (a well established guitar shop) to complain.

Thanks in advance, internet!!

Cheap cable (black) vs standard cable

  • Thanks Todd, For clarification, having seen the photo are you saying I could be getting the shocks through the sleeve touching the wrong connection in a pedal? I've all but ruled out faulty amps and pedals (problem persists with an old Marshall and a brand new Katana) and it's not always the same pedal I have to replace the cable in to resolve it. I've checked all the 6 cheap cables and these 3 are the only ones with the long barrel so they have been removed permanently. – Sam Sep 7 at 15:03
  • There should be nothing carrying high voltage anywhere near an 'outside' contact that could be poked by a small child with a screwdriver [or an adult with 6 beers]. That simply would not pass any country's electrics standards. – Tetsujin Sep 7 at 15:04
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Normally a shock from your guitar strings is caused by a very dangerous fault in your amp. In any case, no part of any cable should have enough of a voltage on it to shock you, so either your amp or one of your pedals is the problem. No matter how badly a cable is wired, it can't be producing any voltage. The shocking voltage is getting into the cable from some power supply in your amp or pedals.

Don't die.

Get your amp checked first, since that's the one with lethal voltages in it. Most pedals are much safer. If your amp checks out, then experiment with your pedals to find out which one is shocking you and get that repaired or replaced.

Ok, after looking more closely at the picture, definitely stop using those cables with the long barrel. That might be causing connections to parts of the pedals or amps that are not supposed to be touched.

  • Get the pedals checked too if they run off mains power. Battery pedals are fine. – Tetsujin Sep 7 at 14:40
  • @Tetsujin Battery pedals at least are not dangerous, but if I were feeling a shock and narrowed it down to a battery powered pedal, I would still want it fixed. A) the shock would be annoying and B) I expect whatever fault would affect both sound and battery life. – Todd Wilcox Sep 7 at 14:42
  • I'm not sure how you could ever get a shock from a 9v battery – Tetsujin Sep 7 at 15:02
  • @Tetsujin Clearly you’ve never touched one to your tongue. – Todd Wilcox Sep 7 at 15:42
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    There's no way to tell without stripping the pedal. Plastic sockets tend to have a 'back' as part of the moulding. Others literally just two bits of spring steel, nothing else. There should be, design-wise, absolutely nothing that could ever possibly get anywhere near any mains voltage behind there, whatever you poke it with. – Tetsujin Sep 8 at 13:10
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Anything connected to mains power has the "potential" to deliver that voltage to unsuspecting guitarists. This could be faulty AC adapters or a faulty amp. Whatever, it is that is causing it needs to be checked. If you have a multimeter or know someone who has one you can check by connecting one prong to earth (ground) and then with the other prong check individually the end of each instrument cable (tip and shaft) to see if the offending voltage is present including a lead directly from the amp. By process of elimination you should be able to isolate the problem. Cheers

Note: set meter to AC volts

  • I have a multimeter but to date just use it for continuity checks (about the limit of my knowledge in this field). I understand what you're advising but want to clarify where the earth is that I connect one prong to. The wall's socket's earth? – Sam Sep 7 at 19:08
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    @Sam For your safety and based on what it seems you know about electronics, I strongly urge you to have a professional check your amp(s) to make sure you are not risking fatal electrocution. Trying to do it yourself is even more risky than having unexplained electric shocks. – Todd Wilcox Sep 7 at 19:22

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