I have just purchased a new 5 watt, class A, all tube amp for my grandson, at an amazing, [to me], price.. I went to YouTube and found out more about it. One guy explained how the 'stock' 220 ohm resistor in the negative feedback loop is way too small. He suggests a resistor value between 20K to 30K to give the amp more punch... Or to put a 50K Ohm Pot in it and adjust it anytime to where it sounds best.. I want to try one of these, but the guy, demonstrating where in the amp, and how to do it, didn't mention the wattage value needed.. Is one watt about right? Or do I need more or less than that? Thanks!