Clean AC power

    OP,   The greasy ’grunge’ that you removed from the breaker clips is called N0-Ox, and is intended to keep the breaker contacts that were covered with it, clean, and free from oxidation. If they were protected, with No-ox, they aren't now. Try try again.

@vgizzi
Generally speaking, everyone’s electrical situation is unique, components differ in their resistance to electrical noise, audio systems differ in their transparencies/resolutions/noise floors, and people have different hearing preferences and abilities.  While you may be able to draw some general conclusions, everyone’s situation is unique.

I suggest trying yourself to see if any sonic upticks- seems most folks do.  To save $ find vendors w free trial or buy used and resell if you’re not satisfied.  

An Audioquest Niagara 1200, AQ Edison receptacle, AQ Thunder power cord to amp, and an AQ Z3 power cord from Niagara to the receptacle. Dedicated circuit 12/2 to 20 amp breaker on panel. Relatively low expenditure but good results. Surplus receptacles provided by a Furman pst-8. One and done! All electrical work performed by me...saved $$$.

Doesn't keeping your audio components on a dedicated circuit protect them from noise generated by other household appliances? If not, what purpose does a dedicated circuit achieve?

4krowme, The grunge I cleaned off wasn’t greasy, or oily like the de-oxit spray. It was the sort of powdery oxidation that’s so common.

Also, I have the same question about a dedicated circuit. What is it actually doing?