Do I need a power conditioner?

Hi leotis, dedicated lines cannot reduce any noise in themselves, but they can gain you a little physical distance between your system and the rest of the noise in the home and that should help at least some, sometimes noticeably. 

There is Always noise present - it's unavoidable - you will just never notice it until it's Gone!

Conditioning solutions do too often spoil the sound in one way or the other. There are perhaps a few types available out there that simply don't have any sonic downsides. Alan Maher Designs is one. I've used that for years and there is nothing but the positives. I don't even need the dedicated lines with that and everything can be plugged into the wall and it works with any kind of amp, no matter how much current or how many watts it draws from the wall.

Regards,

John

@leotis,
I’d like to caution you about circuit amperage, unused circuits in your circuit breaker box and the act of turning off lots of appliances when you listen (longterm). Be aware that a properly designed circuit leg from the breaker box will have a load of around, say, 80-85% of capacity. IOW, if you have a 20 amp circuit, the connected devices should preferably be, say, 15-17 amps...too close to 20 would be considered unsafe, but the concern for audio is too little of a load (longterm, over many weeks). A circuit with consistently much too low of a load will create voltage instability. It’s the voltage instability (again, longterm) that plays havoc with the sound. In many cases, there are more voltage instabilities that originate inside the home than from outside.

If you have a home with all circuit loads at nominal and all circuits see regular daytime use, that will be enough to be conducive to voltage stability and therefor good sound.

But, there is one more point. After the above is secured, the entire issue becomes wholly a matter of GROUNDING! For audio, your home’s ground system should really be inspected every 10 yrs or so, more often if you live in a dry climate. Ground rods corrode, as do connections and wiring (assuming that is all to code to begin with) and many older homes are effectively left electrically without any ground at all. Does that have an effect on the sound?? You bet it does. An effective ground (your local electrician can tell you what is code for your area) will mean better power conditioning performance and/or better system performance even without conditioning.

I don’t know that your sister is so nutty after all ;>)

Agreed, I believe Alan Maher has some legit products for the health end of the market, too (for those who are EMI/RFI sensitive), but is finding it hopelessly full of snake oil and will have to be pulling out of that soon.