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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
three_easy_payments's avatar
three_easy_payments
2,097 posts
 
@cleeds 

It helps reduce voltage drop.

Thanks.  Again, no electrical prowess here.  What would I notice in terms of sound quality during a transient voltage drop caused (at least in part theoretically) by not having enough amperage headroom (i.e. 20A circuit).  Just curious if I could hear the issue when voltage drops, even just briefly.  I guess exploring the power side of audio could be the next rabbit hole for me to obsess over.  ha.
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cleeds
5,961 posts
 
three_easy_payments
What would I notice in terms of sound quality during a transient voltage drop ...
Sorry, but I'm not one of the users here who instruct others on what they will or will not hear. I suggest you listen for yourself.
plga OP
184 posts
 
Well, thats exactly the problem with this "hobby"!!

You have to try it for your self to see the results as YMMV and that's exactly what I will do with this AC dedicated line experiment. 

I will do it in a couple of months and I will let you know my experience.
ieales's avatar
ieales
1,201 posts
 
That way, when big crescendos emerge, you know full current is still available to the rest of the system.
Not so. Full current is supplied by the PSU caps. The wall only supplies current when the cap voltage is lower than the line voltage plus 1 diode drop. See Rod Elliot's http://sound.whsites.net/power-supplies.htm and http://sound.whsites.net/power-supplies.htm#s51 in particular.

In the case of any peak that is out of sync with the line voltage the line supplies ZERO current.

In case of any frequency below the line frequency, the line only supplies current for a portion of the cycle.

In the case of frequencies above the line frequency, the line only supplies current for some of the frequency.

The increase in headroom for over size wiring amounts to about 0.25db. See https://forum.audiogon.com/discussions/headroom-loss-for-1600w-on-14ga-120v
jbhiller's avatar
jbhiller
1,437 posts
 
Wouldn’t it be riskier to use a larger breaker on a circuit than necessary?  If you only draw 5 amps a 30 amp circuit may never trip. That was my understanding. Electricians, here, is that right?
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