Every wire is an antenna promiscuously gathering RFI. Every connection is an interface inviting micro-arcing and all the noise that comes with it into your system. Adding another panels adds:
Another circuit breaker, that’s at least two connections right there.
Another set of bus bars. That’s additional feet of antenna, with multiple connections all along its length.
Another set of neutral and ground wires.
A whole panel case, which let me tell you is far from being a Faraday cage, but it does cost about as much as one, only this one gives you worse sound not better.
People always ask these questions as if the details don’t matter. The details are everything! If you are adding a whole separate building with circuits for light, heat, AC, etc etc AND a stereo, then maybe a panel makes sense. If you are talking about adding a panel for nothing more than a stereo then it makes no sense at all.
The big problem getting solid advice from a sound quality perspective is almost nobody is capable of giving solid advice. In order to do that you would need someone who has actually compared the different methods in the same room with the same system - just the same as you would want for someone reviewing a component. Nobody would ever buy a component based on an electrician saying it meets UL code but has never heard it except in some totally unknown system, and even then only once, no before and after.
But that is exactly what people do with this question all the time! Some electrician (or EE, which is even worse!) rattles off code and everyone listens. When what they should be doing is listening to one who has actually tried and compared results the way you would want with any other component.
Well, here you go.
https://systems.audiogon.com/systems/8367 All done the same way my system was built, one painstakingly careful step after another. You can’t get any more unconventional.
