In my experience after ripping out drywall for ceilings and walls running 4 dedicated lines to a sub breaker box, my issues actually worsened.
The AC power was that dirty in my house - in part from my own computers and electronics and in part from the regional grid - neighbors switch power supplies, etc.
This noise does travel retrograde.
Solution: TORUS Power isolation transformer - I placed a 75A wall mount unit. For those considering one and use tube amplifiers purchase a unit rated for 4x the measured power draw of your amplifiers. If you system draws 10A, then a 40A unit would be appropriate.
The other consideration is RF/EF radiation from LED lights and dimmer switches. The dimmer switches (which function by rapid cycling current) create horrible AC noise that I measured polluting my dedicated lines.
The AC power was that dirty in my house - in part from my own computers and electronics and in part from the regional grid - neighbors switch power supplies, etc.
This noise does travel retrograde.
Solution: TORUS Power isolation transformer - I placed a 75A wall mount unit. For those considering one and use tube amplifiers purchase a unit rated for 4x the measured power draw of your amplifiers. If you system draws 10A, then a 40A unit would be appropriate.
The other consideration is RF/EF radiation from LED lights and dimmer switches. The dimmer switches (which function by rapid cycling current) create horrible AC noise that I measured polluting my dedicated lines.