Sounds like a classic bad mains issue. I had a similar issue with dimming upon load. Turned out to be a bad connector on one of the 120v mains on the power pole. As many above have suggested, call the Power Co. If mains are good, find a better electrician. Beyond that, the rabbit hole is deep.... An isolated ground circuit is helpful, but still shares grounding at the box. I like an a large ungrounded (yeah probably not to code) isolation transformer (larger than the sum of VA or watts of the equipment) to start.....
How To Do You Measure the Quality of Your AC Power?
What is the best way to measure the quality of the AC power feeding your listening room? Is there a device you can plug into an outlet that will give you the voltage, frequency, the total amount of distortion relative to a perfect sine wave, etc.? Furthermore, how would you measure the ability of your AC main to deliver transient currents?
It seems like there may be a scenario where you could measure your power quality to be excellent but somewhere in the line you could have a loose or poorly made wiring connection which under heavy load (such as powerful bass notes) you could run into trouble with power delivery. In this scenario, an AC regenerator would not help you, or would help very little.
Just curious what methods people have come up with to systematically analyze their power and how they use those measurements to drive buying decisions or repair work, if needed.
Edit: My apologies for the title typo.
It seems like there may be a scenario where you could measure your power quality to be excellent but somewhere in the line you could have a loose or poorly made wiring connection which under heavy load (such as powerful bass notes) you could run into trouble with power delivery. In this scenario, an AC regenerator would not help you, or would help very little.
Just curious what methods people have come up with to systematically analyze their power and how they use those measurements to drive buying decisions or repair work, if needed.
Edit: My apologies for the title typo.