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More questions about dedicated lines

We are moving to a new house built in 2007  and I am fortunate enough to be able to move a wall to create a room with golden ratios. I will need to run some new electric and it gives me the opportunity to run dedicated lines.  I have spent countless hours rummaging through the 7k discussions on this topic and have a decent idea of what is needed.  My plans are to have four runs of Romex 10/2, one each for each monoblock VAC signature 200's, my digital, and my Audiokinesis swarm which has not be set up yet.  I estimate the runs to be conservatively 45 feet including up and down distances. All runs will be of equal length ending in SR  outlets. They will be separate from each other and all other lines and no metal staples will be used.  When I told him I my goal was to have the best sound he offered a suggestion that I hadn't come across in my electrical education here on the gon.  He suggested placing what sounded like a commercial power regenerator with a large battery bank as the first step out of the breaker box and running lines from this.  The other options were to run from a preexisting sub panel that has the pool pump and a few lights on it, but nothing else.  Third is straight out the breaker box.  He wanted to put the runs closest to the utility line in, stating that there will be less noise upstream than downstream, but this puts these lines next to a big double breaker (cant' remember what it is but is sure to be noisey).  He understands that I want all lines on the same phase, or line,leg.  My questions are: Of the three options, which would be best?  Is there anything else needed to minimize the risk of ground loop hum if I use separate hot, return, and gound for each line and not share ground neutrals and keep all lines separated from themselves and other lines.  If going through a subpanel with little on it, how do I manage to keep all runs on the same phase without unbalancing the breaker? A third tangential question-Is it best to use metal or plastic housing boxes for the receptacle? The question of durability of the plastic fatiguing and breaking following repeated plugging and unplugging has been mentioned but I didn't see an answer.  Finally, a huge thank you to jea and almarg for their voluminous responses in all the prior electrical discussions-I got an education.  Sadly, I still don't speak electricalese.
orthomead
gdnrbob
4,417 posts
 
@OP, 
I ran 3 direct lines. One for source, and one each for my monoblocks and subs.
The distance from breaker box to outlets varies.
12 feet to amps, 20+ feet to source.

My one concern with choice #2, is having a system on the same line as the pool pump. What happens when both pump and stereo are run at the same time?- Maybe it is a non issue, but, if since you are going this far, why not give yourself every advantage and go the safest route.
Ground loop hum is a b*tch, I have it on my office system, and I wouldn't wish it on anyone.

Hopefully, the electrician will have some time soon...
B
orthomead OP
113 posts
 
Firstly, thanks to everyone for their input.  I suspect this is one of those topics where there may be no perfect approach but the discussion of multiple paths may coalesce into a good solution for my system .
Al, the Elgar sounds awesome-too bad it is no longer produced and supported.  I suspect that the option of running off the main panel may be the best.  gdnrbob, I too am concerned about the pool running during listening times.  If we do run off the main panel, any thoughts about what order in the breaker box the lines should come.  First closest to the mains input with bigger utilities close by or at the end of the line?  Prior discussions seemed to favor distance from the bigger power consumers.

Millercarbon also raises a good point about multiple lines behaving like a big antenna.  All prior posts that I reviewed with single lines had no problems with noise, but not all with multiple lines had issues either.  If I do run multiple lines off the breaker and I do run into noise, I could always place every thing on one line as Millercarbon suggests.  The cost of running extra lines is minimal and it does give me a fail safe. Unfortunately, the electrician was a little nebulous about the actual product he had in mind for a battery bank.  I do like the idea and I will try to pin him down to a more specific and concrete item.  I am open to suggestions if you have them.
There seems to be no consensus on how many lines are necessary and at what point we reach overkill, or worse-more noise.  For spinaker and rodman- what components do you have on each line? Are you running subs on the same line as the main amps?
In terms of grounding, tecknik, my basic understanding is that all grounds have to be interconnected to meet code. My electrician did mention adding another ground though.
audiozenology-I am a little confused.  Do the outlets off the sub panel have a different wiring configuration? Or is it the shorter runs that make the improvement.  Some have suggested that additional connections may be more problematic.
Again, thank you so much for your input
audiozenology
362 posts
 
orthomead,
I am running a single 6 awg connection (line/neutral/ground) to a mini - 6 location panel right behind my system. I only have 3 breakers installed. That runs to 3 double outlets on the other side of the stud. The wire lengths are quite short, about 16". I used 20A outlets as they would accept 10awg. I can always run a separate ground to this mini panel, but don't see a need.
orthomead OP
113 posts
 
audiozenology- Are some lines on a different phase or line,leg? If not, how did you balance the minipanel, or is that only necessary on the main breaker?  This is a point of confusion for me.  If the lines are on different phases to balance the mini panel, doesn't that compromise sound?
jea48
4,313 posts
 
@ orthomead

+1 almarg post on 12-15-2019


almarg9,244 posts

12-15-2019
8:14pm


Regarding keeping the two AC legs from becoming significantly unbalanced, I would infer from the literature on your VAC amps that they operate primarily in class AB, since only the input and driver stages are described as operating in class A. And given their 200 watt rating in mono mode I suspect that aside from occasional very brief dynamic peaks in the music each amp will probably be supplying well under 100 watts to the speakers, with the two amps together consequently drawing no more than about 500 watts of AC. With the system as a whole probably drawing no more than 800 watts or so most of the time, including the sub amp. Which seems to me to be sufficiently low that keeping the legs in balance is a non-issue, regardless of which of the three approaches is chosen.

Using Al’s (almarg) calculations for total average energy usage of 800 watts would not be a problem, imo, putting the four 20 amp dedicated branch circuits on the same Line , leg.


One 120V 20 amp (2400 watts) branch circuit would easily handle a 800 watt load. Spreading, separating, the loads of your audio equipment across 4 branch circuits will not change the total connected load.

800 watts / 120 volts = 6.7 amps. 6.7 amps will not cause a significant imbalance load on the electrical service of your home.
The average portable vacuum cleaner has an FLA of 12 amps. A portable electric space heater 1500 watt @ 125V, 12 amps. An average microwave oven 1200 watts, 10 amps @ 120V.

Using 10-2 with ground Romex (NM sheathed cable) where the total length is 45ft should rule out the chance of ground loop hum..... Should..... I can’t count all the threads I have read over the years where monoblocks were/are used where the user is fighting ground loop hum problems.

Here is just one running now.
https://forum.audiogon.com/discussions/krell-kas-amplifier-hum

@Atmasphere explains most ground loop hum is caused by the audio equipment itself. Poor design in the way the designer connected the circuit ground/signal ground to the AC mains safety equipment grounded chassis of the equipment.

Jim
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