Why am i getting an electric shock from my guitar?

[greyham]

Re: Why am i getting an electric shock from my guitar?

hi, i wonder if anyone can suggest why i am getting a small but quite painful electric shock from my guitar strings when i have my guitar plugged into my roland micro cube and the cube plugged into my laptop via the record out. It only seems to happen when i have the bridge humbucker selected aswell.

any suggestions? bare in mind it only happens when plugged into the cube record out and when the bridge pickup is selected. thanks

I know this was a long time ago but I'm wondering if you got it resolved?

I recently bought a Roland Cube Street, and am finding I get electric shocks from my guitar when using the Roland AC adaptor that came with it. The shocks are mildly painful and certainly distracting when playing. They don't happen when using batteries. Also, they only occur when I'm well grounded, such as standing barefoot on a concrete tile floor or touching grounded metal such as a tap. If I'm standing on carpet or have rubber sole shoes on and am not touching any low resistance grounded material, I don't get them. They're most noticeable on the sensitive inner side of my arm where it rests against the metal bridge on my Stratocaster.

I notice that the Roland AC adaptor isn't grounded. I put my multimeter on its output and measured 115V AC between the output terminals and ground. It would be normal for this voltage to float a little since the input isn't grounded and the output wasn't under load, but 115V is way too high. I get the same voltage measured between the guitar and ground when plugged into the Cube Street, which is why I'm getting shocks. I'm in Australia so the input to the adaptor is 240V. When I use the 9V power supply from my guitar effects pedals, I don't get the shocks and the multimeter on that adaptor only measures a few volts between its output and ground.

I took my Cube, guitar and AC adaptor into the store I bought it from and couldn't reproduce the shocks, but I only realised later that I was standing on carpet in the store so I wasn't well grounded. They swapped my adaptor for the demo model and when I tried the second adaptor at home I still got shocks; so it's unlikely to be a manufacturing fault in the AC adaptor. It appears to be a design fault; although you'd think someone else would have noticed by now. Maybe electric guitar players think being shocked on stage is too cool to report to the company?!?

Anyone else had shocks from equipment powered by the Roland 9V AC adaptor?

Cheers,
Graham

 

[Mincer]

Re: Why am i getting an electric shock from my guitar?

Welcome to the forum!

Can you bring your rig to another building that doesn't have carpet? So far, we know it only happens at home, and I know I've used Roland gear in my home with adapters and bare floors with no shocks. Have you tried this in several different rooms of your home?

 

[greyham]

Re: Why am i getting an electric shock from my guitar?

Can you bring your rig to another building that doesn't have carpet? So far, we know it only happens at home, and I know I've used Roland gear in my home with adapters and bare floors with no shocks. Have you tried this in several different rooms of your home?

Thanks for your response. Yes, I tried it in an entirely different building, and the result is the same. The local Roland technician says that the amp needs to be grounded; there is a grounding terminal on the back just above the power input. That would solve the problem, but it's really inconvenient. When I run it with a non-Roland power supply, I get no shock; so I'm just going to do that.

Thanks,
Graham