You could be right; the view was still not found when I tried it again. However, it did show up in one-half second, and then it went dark. I guess I will miss another bargain-of-century cable, but with the tariff it may not be that great a deal anyway. 
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Grounding isnât simple. A current will seek the LOWEST potential path to true earth or signal ground (not the same thing). A wire has a DCR, and that changes the potential form one end to the other thus current will flow from one end to the other. It gets more complicated than that, we have the length of the wire and ANY conductive path (the chassis material and PC board lay-out) to worry about.
Use ONE wall outlet if you can. This keeps the final ground path low to the box. Sometimes changing your circuit will show benefit just moving the reference to the circuit box around. Not all grounds are the same.
Stuff that has a high S/N ratio has a well designed internal lay-out to achieve those -100 dB numbers. Thatâs your first check.
The second is the RCAâs design to use the shield as a signal return path. We need that path to be âzeroâ DCR. The higher it gets, the higher the noise floor rises. It is just how it works. Change your RCAâs to shorter and heavier ground shields. RF isnât your major problem, the shield DCR is. XLR float the ground between two signal levels, this removes the âgroundâ path. We only have potential voltage in the cord. To do this we add some stuff that has other problems but it does remove grounding issues.
Third is the imbalance we create to the wall with the power cord. Using a heavier power cord for high current stuff helps. The voltage drop across the cord is the cords DCR times the current in the cord. We canât escape that. Donât go too crazy, the cordâs current determines the appropriate cordâs AWG. A turntable doesnât need a 10 AWG AC cord.
These so called ground boxes are usually UNGROUND boxes or floating grounds. They âfloatâ the ground as a possible return path forcing the signal to find ground elsewhere, it canât find any other way out!
If you look at a PC server for music, the PCIe bus can have several return paths to the power supply. As many as ten or more paths! As the ground is overused, it heats up literally (power is heat in the ground path and is amps time volts), and this changes the balance as to what is the lowest DCR path. Electricity is smart, and this âbalanceâ changes with the load current grounded.
The newer PS Audio stuff also manages the ground with isolation, this makes the grounds what the designer wants, and less what just âhappensâ. A lot of our systems are exactly that, what happens.
Galen
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Thatâs a brain dump and a half, but a good one. Galenâs dead right about ground not being some static, magical point, itâs dynamic, affected by everything from layout to load. Most people slap on a grounding box without thinking about where and why theyâre grounding. Floating vs chassis vs signal ground, it all matters. Honestly, unless youâre working with balanced connections or well-designed internal layouts, youâre probably just moving noise around. Makes me think half the tweaks people chase could be solved with proper layout and one clean AC source.
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