I'll just throw in a couple comments on power delivery.
I have a dedicated breaker, cabling, and outlet going to my speaker system. In that room, I have a ceiling fan (not getting power from that breaker). When I turn the fan off/on, I get a slight "pop" through the speakers.
So, there are only two paths for that spike to get back to the audio system: 1) Through the air; or 2) Back to the breaker panel and out through every wire in the house.
This means I haven't accomplished isolation by just putting in a dedicated breaker. I would need to have a dedicated line to the house & separate box, right? Or is there such a thing as a higher quality breaker with isolation, chokes, etc?
Anyway, one for ya all to chew on.
My vote of the path for the 'pop' is thru either the neutral or ground, or both, since these wires are tied together in the panel, along with all the rest of the branch circuits back in the panel.
Motors, when power is 'quickly' disconnected tend to 'spike' the supply circuits.
Some motors are 'impedance protected', which usually means a capacitor has been added to 'absorb' these spikes.
Some are more successful than others in this regard.
One other 'possible' solution is to ground the entire audio system independently of the ground buss in the panel.
This entails a separate ground rod and run to the power that feeds the audio system.
I was amazed at the SQ differences I heard just by soldering the ground wires together where previously they were just wire nutted together on my dedicated branch circuit.
This leads me to want to explore this further, so I'm about to implement this as an experiment in my system, just because I can.
I'm interested in hearing what changes this will make.
And my understanding is the most significant reason for a dedicated branch circuit from the panel to the audio system is the increase in being able to dump more current into the equipment, in a very short time.
As I've been investigating this aspect of powering our equipment and what can be done to help improve our systems, the ASCC (Available Short Circuit Current) tests have thus far correlated the most, with noticeable improvements in SQ and in multiple ways.
And since ALL the grounds and neutrals are tied together on the same buss back at the panel, 'real' isolation isn't really possible.
Even the power feeds tie together, thru the breakers, back into the main buss, at least all those that share the same phase do so.
Which means you 'might' be able to reduce the amount of the 'pop' by moving either your dedicated branch circuit that feeds your audio system or the branch circuit that feeds your ceiling fan to the 'other' phase back in the panel.
This will isolate the power from these 2 branch circuits from each other as much as possible without having to add additional equipment.
I'd opt to move the ceiling fan branch circuit, especially if the power that feeds your audio branch circuit is 'clean' and has no other issues other than the 'pop'.
It might be worth a try just to see if it helps.
JJ