I've got a Marshall MG-15 CDR (http://www.marshallamps.com/product.asp?productCode=MG15CDR&pageType=SPECS). Anyway, I heard that if you mess up things you can end blowing up your amp so I wanted some advice.
Also, has anyone tried these http://www.voxamps.co.uk/amplug/ They look cool but I dont understand how they completely work. Anyway, thanks for the help


