Finally converted one of my American sound system amplifiers from Yank (110/120V) to 240V. I've been running them through a massive 3KW step-down transformer for a dozen years (since I moved overseas) because the power transformers were weird toroidal things and completely undocumented. Get it wrong and it's a cloud of white smoke and you've got an expensive door stop. I finally just choked down some coffee and said "Right - I can do this". Anyway, it worked and I'm finally free of the light-dimming step-down transformer. Well I will be as soon as I convert the other amplifier. They're identical twins so the second one will be easy.