crimsonbasser asked: Hey man, I have two amps (Sunn Solarus and Traynor Bass Master Mark II) that shock me when I play without shoes on. Pretty sure this means they're not grounded. I check both plugs, neither have the ground pin connected to anything and the electrical cable itself has no shield or ground in it. If I was to replace that power cable with one with a ground, will that fix the problem? Pretty it should be that way anyways. Also, where should I attach the ground lead?

That does sound like they’re not grounded — but not just that, there’s also an AC leakage problem that needs to be addressed. If I read you correctly, the amps have had a grounded plug installed on an ungrounded 2-conductor power cable? If so, that’s unconscionable.

There is only one right way to install a grounded power cable, and many many wrong ways. The ground conductor needs to be bolted to the chassis with its OWN bolt/nut/washers, ensuring good conductivity with the chassis and secure connection. The hot conductor needs to connect FIRST to the line fuse, then to the power switch. The neutral needs to connect preferably to the other pole of a DPDT power switch and then to the transformer, or to the power transformer primary if the power switch is single-pole. Any caps across the hot/neutral need to be Class Y. There should NOT be caps from the hot or neutral to chassis, and there should be no way to reverse the mains polarity.

In many old amps, shocks are a product of mains polarity being reversed or a “ground cap” (aka “death cap”) leaking mains AC onto the chassis. Grounding the chassis will take care of this, but then there are currents flowing in the safety ground that shouldn’t be there. The leakage has to be eliminated.

I cannot stress this enough: Mains wiring is dangerous and can be LETHAL if not done correctly. If you are even SLIGHTLY unsure of what you are doing, please take the amps to a professional and do not risk your life.