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 .
128x128audioman58
My Electrician friend did the work and has a Masters license
it is connected to both audio outlets, then grounded to the main ground in the box I believe not positive ,for sure it is much quieter
and 2 other friends did the same thing with Excellent results 
they have World class systems over $100k with $3k  line conditioners before hand. Please see the link below.
https://spyrkaelectric.com/heres-what-you-need-to-know-about-an-isolated-ground-receptacle/
Hello Wig, see my link above ,a Dedicated circuit + isolated ground which is insulated also 
from Connection to connection.
For the. Record ,their seems to be some confusion here,I can’t guarantee every buzz will be eliminated I am no expert. I just know myself and 2 other Audiophile friends can clearly hear the improvements. As the electrician said even if you have a dedicated line ,if the ground is not dedicated totally isolated ,then it potentially can share ground noise off other electrical branches .and if in a condo even much more so . I am just sharing with what worked real well myself and others.
I am using AUdio advisor gold copper outlets very heavy duty 
with big HD ground screw on the bottom .$100 each but super 
heavy duty Built no brass .
Agree with @atmasphere and @andy2. Ground-loop is caused by components having different ground potential. This begins with the design of the grounding scheme. Some designs share a signal ground and a safety ground, or some components don't have the earth ground bonded to the chassis.

I agree that wiring the duplex
with an isolated ground to the  circuit panel ground does reduce noise from other devices and appliances in the home. Using a self-grounded receptacle is not the way to go.