My amp gave me an electric shock.........

Does your amp have a ground switch on the back? These are usually 3 position switches, the center position typically grounds the chassis to the 3rd (ground) prong on the amp's power plug (well at least here in the US). The other two positions "grounds" the chassis through a capacitor to either the + or - side of the AC supply. The capacitor may be leaking a little, this is a severe duty for a capacitor.

Some amps don't have a switch but still have caps between the legs of the power supply, maybe if the amp wasn't grounded and one of these caps is leaking a tad...

It's also possible YOUR amp is fine--and whatever you were touching wasn't grounded properly. Of course, if this occurred no matter where you were or what you were touching, that rules that theory out...

Here's a good article, the last paragraph mentions instrument amps

http://sound.westhost.com/psu-wiring.htm

 

Q: Were you powering your pedals by battery or by power adapter?

One of my guitar players used to get shocked constantly because the power strip that he plugged his power adapters into was missing the ground in its plug i.e some one had converted it from a 3 prong to a 2 prong. Gave him a new strip and everything was fine.

Q: What head are you using?

If the biasing transistor has developed a short it may casue some juice to leak to the what ever it is attached to, which may be attached to the chassis. I had that happen to me once with my SM400. It was however also accompanied by intermittent distortion.

It seems like you are being careful but PLEASE be careful.

 

My guitarists old amp used to send an electric current through the guitar sometimes, or whenever you touch the amps knobs. Sometimes when you touch the strings it would zap you with that shock feeling that those palm-buzzers give you. It was a weird old peavey. Needless to say he doesnt use that amp anymore.

 

Check the outlet you were using; maybe it's wired wrong.

 

What was the floor material?
Always plug the inputs first, then the warts into the strip, be sure the strip and your amp are fed from the same outlet, the last thing you plug in is the amp AC. If there is a fault you want all your peripherals grounded together first before you energize the system.

 

I think that tends to only be in the US that switch is there on amps

 

The ground switch is a relic from the days of 2 wire AC. When the chassis is grounded via the 3rd lug a groundswitch is unnecessary.

 

Ah right, its just you still only really see it in US made amps as over here at least we've been three prong for ages

 

Weird. I assume its the pedalboard then.

I'd try this with a voltmeter if you have one, but if not, feeling a shock (or not) is good enough test... =bad, =good when you touch it...

Plug the pedalboard into the wall. Plug a guitar cable into the pedal board, hold that and touch something grounded. See if you get a shock or AC voltage.

Plug a cable into the amp, hold that and touch something grounded. See if you get a shock, or AC voltage.

Thats it, nothing else gets plugged into the wall. One of them has to be hot to get you in trouble, and it happened with another amp, so the only thing left is the pedal board. Probably one of the power supplies is bad, putting voltage on the ground of one of the pedals. They're all powered by wall warts, so they're not really grounded, so connecting them together passes the voltage to all the pedals, waiting to shock you when you touch the ungrounded "ground" connector of the cord going to the the pedals and something else that really IS grounded.

Now disconnect all the pedals from each other, so they're all isolated. Plug them all into the wall. Touch the ground of each one while touching something really grounded until you find the 1 pedal that is causing the problem.

Unless you're getting a shock by holding guitar and touching a mic, then the PA is the one with the grounding problem...

Randy

 

I've got a spare adaptor if you need to borrow one Pete.

 

wow, this thread is scary...

 

I'm feeling rather psychic...

Randy

 

This points out a good reason for having all your effects mounted on a pedalboard with a single high quality DC power supply for all. Not only would this ensure your safety, it would also likely clean up your sound having a well filtered and regulated DC supply.

 

I've been shocked through my guitar strings as a result of using my Electro Harmonix Hot Tubes overdrive. It has a funny 2 prong plug that plugs into the pedal. Gave me a nasty buzz, but I forgave it because it sounds so nice!