Hello. I have acquired a Valve Jr Head V2 and it has a Hammond OT installed so I opened the amp up to take a look at the inside to see if anything else was changed. There were a few resistors and caps that were replaced but the thing that throws me off is the BROWN wire that runs from the AC in to the power switch. There is a 25 watt 20 Ohm resistor installed in line. Can any one tell me why they would do that? Thank you. New Info: I got to try the amp out today and it was dead quiet till about half way then there was some volume. Cranked all the way up it's clean and not loud at all. So I replaced the (El84) that is labeled 6BQ5 USA GM DELCO with a JJ EL84 and the amp is louder than my other head. I couldn't find much info on the GM tube. Any thoughts? Thanks.