Wire the House A/C or get Power Conditioner?

Power conditioner first;the amount of money involved will be far less than dedicated lines. If whatever problem you think you have is still audible, take the next step. I think it is odd not so long ago "ultra" cables,cleanpower,outlets,power cords, etc. were never a concern. Input, amplification, speakers were it. Once the basics are covered, someone somewhere will tell you about a problem you didn't know you had and offer a solution to your newly revealed system flaw. Spend as much as you want, convince yourself that it makes an audible improvement. Good Luck. I'm spending my money on music.

Rushton;
Interesting view on isolated grounds . Your method may be less involved .

How would you address the noise/interference issue , transmitted through the lines , from things like digital equipment , electric motors and flourecent lighting ?
I don't understand how you are 'isolating' the dedicated lines from the rest of the household system if you are connecting everything to the same ground .

Oh , and a happy electrcian often does better & 'more' work than an aggravated one ! And may charge less !

However , I will admit to running my lines with 10g. wire , which did receive a comment !
But I also fished all of that wire from the panel to the box's and pounded the ground rod , in the middle of a Florida summer !

No flames , just knowledge .

what's the best bang for buck power conditioner? PS audio?

I like the APC s15 or s20. PS Audio's are great too, but don't have the batter back up.

Saki70, as explained by an Audiogon member who is an electrician in another Audiogon thread several years ago (that I can't find now), what the isolated ground does is prevent the ground from being connected to the chassis of the receptacle. With both isolated ground and a non-isolated ground installations, the ground comes back to exactly the same place on the bus bar of the breaker panel. The only difference is in whether the ground is connected to the chassis of the receptacle.

If the receptacle and enclosing outlet box are attached to metal studs in commercial construction, the chassis is now making contact with the metal stud and hence to the rest of the building structure. With the ground being connected to the chassis (not isolated), your ground is now connected to the entire building structure. That can make for all sorts of noise, interference and hum possibilities. So, in commercial construction, you'd absolutely want to isolate the ground from the chassis: i.e., use an isolated ground receptacle and wiring installation.

On the other hand, in wood stud construction, the outlet and chassis are nailed to the non-conductive wood stud. There is nothing from which you need to isolate the ground. It no longer matters that the ground wire is not isolated from the chassis of the receptacle.

There is one other possible factor and that is the possibility of the fourth wire in the isolated ground installation providing some EFI drain or shielding for the length of cable back to the circuit panel. I don't know about that contention. I think you'd be better served by taking the trouble to twist the wires which make up the cable if you're trying to get maximum EFI rejection along the length of the cable.
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