Hello keepers of the magic smoke... I have a question, a bit elementary, but you all have the knowledge and experience... I have recently added a variac to my collection of tools for my amp builds... I have used it for a few things, but went to use it for an amp start up on a new build that I wanted to bring up slowly... One of the first things I do when testing a new build is to simply make sure that I have the proper ~120 VAC on the power switch. In this case I was starting up a 5F6A build and on the power switch you have the hot from the line AC on one side of the switch and in this case two hot wires for the (ClassicTone) transformer. Simple right, flip the switch and you pass power to the transformer (as the AC commons are hard connected). So this was the first time that I was using the variac in this step, as it is a quick test and I move on, and by using I just mean that I had the amp plugged into the variac and the variac set to 120VAC. My surprise was to find when I measured from chassis ground to the switch, I found the 120V on the Transformer side of the switch with the switch off. Yes, everything is wired correctly inside the amp hot to hot, common to common. I guess I could expect this if the hot and common were reversed in a normal outlet (sans variac). But with a three pin grounded outlet built into the variac I should not see the polarity reversed. At least that is what I am looking for confirmation on... I also need to make sure the out the Variac was plugged into was not reversed... Am I over thinking this, and there is a simple explanation or is there magic in the variac?