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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
lowrider57's avatar
lowrider57
5,418 posts
 
he reworked the single panel, keeping the larger draw appliances "away" from the music lines in, on the opposite side of the panel.
There are many threads related to this concept, consensus seems to be keeping high-current-draw appliances and SMPS devices away from audio circuits. I mean keeping a physical distance on the service panel for the audio line’s hot and neutral; ie, audio line breakers near top of panel. Refrigerator, air conditioner, etc. located lower.

My panel with subpanel is wired this way, although I disagree with all high current appliances wired to the opposite leg. The service panel must have a relatively even current draw on each leg.

I differ to @jea48 and @almarg on this subject.



redlenses03
105 posts
 
With regards to running everything through one outlet, what are the limits to this?  One Outlet/single circuit are rated to handle only so much?

Being my rig is split
- class A monos and dual subs behind spkrs all plugged into a good 4 plug distribution box (no conditioning) which is then plugged into single outlet on front wall

- my “front end” rack off to the side all plugged into a conditioner (tube pre, tube dac, streamer end point, fiber converter, LPS’s) and conditioner plugged into one outlet on aids wall.

Not that this is uncommon, but is the key in this config for all components in their respective “area” to be all plugged into a single distribution block, conditioner etc..?

i thought about running sep circuits but sev people in my circle say don’t bother as the power sub stations where we are are located have been “updated” and money would be better spent in other areas. 
noromance's avatar
noromance
10,498 posts
 
I tried 2 x 20amp 12ga lines once and got hum.
I’ve been running 1 x 20amp 8ga line for years and it is super quiet and sounds great. (it did when I first implemented it so I guess it's still good.)
Electrical inspector was bemused but said it was fine.
pinthrift
212 posts
 
Thanks millercarbon and lowrider57 for your thoughts around the positioning of the dedicated audio lines on the electrical panel.  I live about 1/2 mile from a large radio tower and pollution is a true concern.

As these things go, two days ago I began sampling a set of Varastarr Grand Illusion Evo Series 10' speaker cables that belong to a friend.  Varastarr claims RFI within and without one's audio chain is addressed by having their cables on-board.  Proof's in the puddin'...yep, more of my truth and these are stayin' put!  More Peace, Pin  
 
jea48
4,871 posts
 
he reworked the single panel, keeping the larger draw appliances "away" from the music lines in, on the opposite side of the panel.


Well, that’s a new one.

Behind the panel where most never look are two great big bus bars. All the breakers attach to the bus bars. These things are so thick it can’t matter where on the bar you take off.
How about the magnetic field surrounding the breaker? Will the magnetic field be stronger in a higher current loaded breaker than one with a small connected load? How about them harmonics on the circuit?

All the circuits, every single one of them, they are all just as electrically connected to every other circuit on one side as on another. The only thing putting a lot of them on one leg can accomplish is to draw more from that leg.

What’s the average connected load of a typical audio system? 8 to 10 amps tops?


Why install all dedicated circuits on the same Line, Leg?

"Less than 300 microamps of ground loop current can cause hum as it flows in an unbalanced audio interconnect cable. However, harmonics of 60Hz that are generated from lighting dimmers or switch-mode power supplies sound like Buzzz mixed with a bit of Hummm and are more easily coupled by even smaller currents. Harmonics can add together when equipment is powered from different phases, so clearly there is an advantage to specifying same-phase electrical service to power the electronics systems in most cases....

Any leakage currents on the safety ground wires of split single phase load circuits fed by different phase legs will add together due to the 240V potential difference....

Power conditioners do not solve any of these common problems: Cross phase coupling (doubles hums & buzzes) .... What actually does solve them: Same phase power.

.

Split Single Phase electrical service is most commonly found in residences and smaller commercial buildings, and is commonly used to feed AV equipment. One key advantage that single phase has over three phase is that while harmonic currents are still present, it is not possible for the �triplen� components to add in the neutral. In addition, use of split single phase can result in at least a 6dB reduction in noise floor as compared to three phase if the capacitances of the connected equipment are relatively well balanced. However, any leakage currents on the safety ground wires of split single phase load circuits fed by different phase legs will add together due to the 240V potential difference."
http://www.exactpower.com/elite/assets/pdfs/theTRUTH.pdf
https://info.legrandav.com/l/71782/2018-12-14/7zh25n

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