Seriously, if one is going to get into this electronics/electrical/audiophile game, then short cuts really don't cut it. The ones that do use short cuts end up paying in the end. As the old saying goes, there ain't no such thing as a free lunch. You don't use permanent cheater plug, you don't permanently lift the ground. You find out where the problem is in your system and you fix it the correct way. In this case as in many. Do it right the first time. 1) run dedicated lines first. This means completely separate hot, neutral and grounds per dedicated lines. Do not share neutrals with other circuits. 2) If hum exist in the system, follow the detailed instructions posted by myself and many others. and trace it back to the offending piece of equipment and either fix it or replace it. As I mentioned earlier, it really doesn't cost much for a qualified electrician to run dedicated lines. They know what they are doing. Some charge based on where you live (stay away from those types). Running dedicated lines is pretty basic. Either from the attic down the wall from the panel or from under the house up the wall, or along the walls. If you have plaster walls (the best) some patching is required, which is pretty easy. If you have drywall, well, drywall is pretty inexpensive to replace. do the dedicated lines anyway. You will hear an immediate improvement. But hum is either equipment based (noisy transformer, internal vibration, etc. or a ground loop.
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