Hey my fellow guitarists A few months ago I built a 4x12 replica Marshall 1960B cab, with celestion vintage 30s. I love them and think they sound awsome. When I built the cab I put cable in that wasnt very thick becuase I was using a 15watt head. But this week I have a 1959SLP that I ordered, and I want to re-wire the cab for some thicker wire to handle the 100w head. I have read about how different gauges effect sound quality, resistance and load. Also that it can damage the amp if its having to do extra work. Im just wanting to know what the best gauge to use, ive heard 12, 16 and 18 are good gauges, I know that to check the gauge you have to measure the thickness, but is it the thickness of the actuall copper wire or the measuring from the complete thickness with the plastic insulator included? I live in england, so im not sure weather it will be SWG or AWG. Thanks guys . Rock on.