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AC Dedicated Line

Hello guys
I will run three (3) dedicated AC power lines: one for my stereo system (power amp, preamp, DAC, etc) and two for my stereo subwoofers (one line for each one).

These three circuits will be connected directly to the main AC board of the Electrical Comany wich provides me the service right at my door.

They will all share the same ground cable, wich I will connect to a dedicated ground bar, but I would like your opinion about sharing the "same neutral line" on these circuits. Could it affect the sound quality? 

If I have to send three different neutral cables, one for each circuit, I will need more cable to run through the house and it will be more expensive and complicated.

Please I would appreciate responses with real experiences. I don't want to start a technical discussion. I know at the end, in the main board, they all will share the same neutral line, so electrically it should be the same, but in this crazy audio world who knows for sure if soundwise it will be the same....

PS: by the way, I will run 4 or 6 mm2 cables (I guess about 11 to 9 AWG on the US scale). Here in Argentina we measure cables by square millimitres.
plga
delkal
110 posts
 
With AC the neutral wire carries as much amperage as the hot wire (the current goes back and forth). You cant hook up 3 hots to one neural and expect the neutral line to carry 3X the current. And how were you planning on wiring one neutral to three different breakers?
Were you planning on using just one 4 strand romex and using 3 as hots and one as neutral. I am pretty sure that would be against all codes in any country. You would be better off installing two outlets with the 4 strand cable with one hot and one neural to every breaker.(assuming that is allowed). Two 20 amp breakers should be more than enough for any sane system. You don’t need 60 amps with incorrect wiring.
almarg's avatar
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almarg
9,670 posts
 
I would just add to the foregoing comments that using a single neutral run for the three dedicated lines, all of which would presumably be on a single phase in your country, would seem likely to negate whatever benefit having multiple dedicated lines might otherwise provide. As indicated in the preceding post whatever amount of current is conducted by the hot wire that is connected to a given component is also conducted by the neutral wire that is connected to that component. So commingling the AC currents drawn by all of the components in that single neutral wire would seem likely to make the three dedicated lines essentially non-dedicated in terms of any potential benefits.

Regards,
-- Al

purplegoose
11 posts
 
Use a separate common for  each circuit from the receptical to the power board. You should consider a quality power condishiner.  I hooked one up to my tube amp and all the hum dissapeared without any need for extra wiring . I was going to do the same thing as you have planned. Good luck. 
rbstehno
1,431 posts
 
I don’t agree that running 1 - 20amp circuit is all you need. Without knowing all the equipment you have today or you will get in the future, why only put in 1 circuit when running wire for 2 or more circuits isn’t that much more?
I agree, you need to see how much power you are pulling when everything gets powered up. To do this, have an electrician place their meter around the wire in the box to see the actual amps you are pulling. I did this 20 years ago and you would be surprised to see how many actual amps you draw. 
On top of that, you want to give yourself some headroom, meaning if you are pulling 12 -15 amps, I would go with multiple dedicated circuits.
I built my last 2 houses with dedicated listening rooms and each room I had them pull 4 dedicated 20 amp circuits, I think it cost me $450 for these. Better to do it before the drywall goes up or it gets much more expensive
plga OP
184 posts
 
Thank you guys!

Im sorry, may be I wasn't clear enough.

The main power of my home is triphasic and, from the main board, all the monophasic circuits are connected to somehow balance each phase with similar current.

All the circuits share the same neutral. Its been running ok since 10 years and the electricity bill is cheaper here with triphasic. 

I first thought that connecting each of the three circuits to a different phase would provide better results as each one would be better isolated from the rest. Nevertheless, I think I find millercarbon's advice very useful and I will make it simple and just run one circuit with dedicated ground for the whole system and the subs.

PS: I already have two budget power conditioners (AC filter and a DC Blocker) and they are doing a great job, but at nights, when the power is cleaner, the sound is just so incredible that I want to give it a shot and try this dedicated circuit to see if it makes a difference. Many people claim that it helps a lot. 
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