I completely renovated my home 14 yrs ago. My electrician ran ground from panels to 2 outside half in 8 ft copper rods in the ground. 200 amp service. When completely rewiring the home I had him run 4 separate 20 amp circuits 12/2 for my back wall audio equipment only. I put in 2 gang boxes, each was 20 amp with neutral and ground. I have never heard any humming or noise at all. All the other outlets in the room are a separate 20 and lights on a 15. As far as any other dedicated circuit way, I can not speak. The 4 separate circuits are for audio only and tv. No issues. Also have an intermatic on the main panel. I think it was 125.00 at the time. Many older homes did run same circuits in other rooms. As I said, older homes.
How to guarantee to lower noise- ground loops in your system
I have been through many problem area where noise in the audio chain was a problem.
my friend Who is a Electrician solved the problem . All too many times people add a dedicated 20 amp circuit 12awg is standard 11-10awg even better lower resistance , also most important
you need a Isolated dedicated ground, this is totally insulated right back to the earth ground in the
breaker box this will dramatically lower your noise floor and remove ground loop problems .many people just put a dedicated line and think
that’s it ,not so, if you are going to go through the trouble, then for maybe $100 more the isolated dedicated ground to the dedicated circuit is a must. I can tell you without question .
my Audio has a noticably quieter background .in songs i now hear low level musical artifacts like reverb off a guitar fading cymbals and clearer seperation of instruments .well worth the effort .Hopefully
this will help others .this is a essential system upgrade .
my friend Who is a Electrician solved the problem . All too many times people add a dedicated 20 amp circuit 12awg is standard 11-10awg even better lower resistance , also most important
you need a Isolated dedicated ground, this is totally insulated right back to the earth ground in the
breaker box this will dramatically lower your noise floor and remove ground loop problems .many people just put a dedicated line and think
that’s it ,not so, if you are going to go through the trouble, then for maybe $100 more the isolated dedicated ground to the dedicated circuit is a must. I can tell you without question .
my Audio has a noticably quieter background .in songs i now hear low level musical artifacts like reverb off a guitar fading cymbals and clearer seperation of instruments .well worth the effort .Hopefully
this will help others .this is a essential system upgrade .