I've searched a bit but haven't found exactly the right answer. Thanks in advance for the lesson in basic electronics. I have a Valve Jr head and I'm considering upgrading the output transformer. I like the low output of the amp and I'm not really looking to increase that. I'm considering the Hammond 125 line and I see there's a difference in power ratings between the CSE, DSE, and ESE (8, 10, and 15w respectively). Does the output transformer actually change the output of the amp to it's rating (ie. a DSE equipped amp would change from 5w to 10w)? How do you determine which OT to use? On the same note, I've searched for the more popular mod kits for the Jr and found few actually describe what changes when the mod is done. I don't suppose someone would be kind enough to break down the common mods to layman terms? Or maybe just point the way to a site that does?