@emergingsoul said:
My question focused on noise which is the issue. And if there’s no noise coming from the neutral, and the ground, assuming these are connected correctly at the panel, and the panel secures the ground via a stake in the dirt, what is the problem??
I have answered your question(s) several times throughout this thread. In about every variation I can think of that gives the same answer to your question(s).
You keep talking about noise on the neutral and the ground conductor. I don’t know where you are getting that from... The problem with audio equipment fed from a MWBC, (Multi Wire Branch Circuit), is not caused from the shared neutral or EGC, (Equipment Grounding Conductor). It caused by the Balanced L1 120V loads being connected in series with the L2 120V loads. You couldn’t find a better way to couple the 120V power supplies of your audio equipment together than using a MWBC to feed them.
JMHO, you would probably be better off just using one of the circuits, (turn the other one off at the panel), and power all your audio equipment just off the one. Pick up a good quality power strip for more outlets if needed.
As I have said several times in this thread the 120V L1 and 120V L2 Balanced loads (current) are in series with one another. The Noise you speak of comes from the power supplies of digital equipment, as well as any cheap made SMPS. There is your noise... The use of a MWBC dumps it right onto the primary winding(s) of the power supplies of the analog equipment. (Preamp, Power Amp, ect)
Maybe you don’t have any digital equipment or equipment with SMPS. Then there is a good chance a MWBC works fine for you. Or if you do have digital front equipment and SMPS maybe the designers/manufacturer spent the extra money to add filtering to prevent digital hash from going back out onto the mains. And maybe the designer/manufacturer of SMPS(s) spent the extra money on the build quality of the SMPS(s) and filtering to prevent bad harmonics from going back out on the mains.
.
FWIW, If your audio system sounds good to you that’s all that maters.
FWIW, you could have a new dedicated circuit installed, (10/2 Romex), and then have the electrician change the MWBC to just a two wire Hot & neurtral + grd dedicated branch circuit. Make sure the electrician feeds the two dedicated branch circuits from the same Line, Leg. Both from L1 or both from L2...
Any Electrician worth his salt can rework the panel circuits to free up two breakers that are both on the same Line, Leg.
I strongly suggest you don’t use the last electrician the installed the MWBC...