The "tarnish", or oxidation that silver experiences has absolutely no effect on it's conductivity(unlike other metals), as anyone that has paid attention "realizes". That's unless said silver is exposed to high concentrations of H2S, SO2, NO2, CL2 or ammonia, and the corrosion becomes pretty thick(highly unlikely in your listening room, unless you create a lot of Hydrogen Sulfide via flatulence). Gold is among the most inert materials in the world and, as such, will not significantly contribute to any electrolytic process. "Alchemy?" As usual: The inexperienced and unknowing, decrying experiments, conclusions and science from their pulpits of abject ignorance. You're welcome to "The Last Word!" (I doubt that you'll be able to help yourself.) =8^)