Whole House Mains Wiring -- Ping: Jea48 (Jim) -- & ALL Others for your HELP!

Nice post Mrmb.

Flexibility and Ethernet.

Consider a sub-panel, which will make any future changes and expansions a lot easier.  Whether lighting, projection, who knows. Having a sub-panel makes changes easier.

Also, I do not like to rely on WiFi for streaming. Mainly due to reliability issues, either from the crappy routers themselves to channel congestion and who knows what else. So make sure you have Ethernet run at the same time.

Best,

E

Re. Almarg:  I should have been more explicit when I referred in the previous communication to "3-conductor Romex (e.g., 12-2 with ground)," and subsequently to "3-conductor Romex." My reference to three conductors included the ground conductor, so I was referring to "12-2 with ground" and not to 12-3. The additional "hot" conductor in 12-3 would serve no purpose in this situation, and if that conductor were used to carry a current the benefit of the symmetry I referred to between the current conductors and the ground wire in 12-2 would likely be negated.

 From an AudioCircle Thread:  "I was given this advice from the design engineer of a well known Audiophile Power Conditioner manufacturer."
"Use round Romex 10/3 or 12/3. Inside are 4 wires, a black, white, red and bare wire(s). Use black for hot, white for neutral, the red and the bare are both for ground (using 2 wires for ground gives you a much lower impedance path to earth ground resulting in a quieter system with a lower noise floor). If you do 2 dedicated circuits, make the wire length identical for both if at all possible."

And another A/Circle post:  "The 10/3 (plus ground) Romex® NMB is typically used for split phase 240V circuits. But the 3 conductor (+G) has a virtue when used in 120V circuits (one wire is not connected) that virtue is that it has a natural twist which reduces interference."

Al, I found the above.  So, when you mentioned 12/3, it correlated with what others had said.  So, perhaps 12/3 if installed, does have some benefit? 

But if  I would like to hear that others agree it does have benefit and if so, how should 12/3 or 10/3 it be installed?

Consider a sub-panel, which will make any future changes and expansions a lot easier. Whether lighting, projection, who knows. Having a sub-panel makes changes easier.

Also, I do not like to rely on WiFi for streaming. Mainly due to reliability issues, either from the crappy routers themselves to channel congestion and who knows what else. So make sure you have Ethernet run at the same time.

The sub-panel was estimated in the electrician's quote, so I plan to solely keep my A/V (2-channel room and (2) 7.2 rooms) and nothing else! 

I don't know yet where the load panels will be, but my goal is to have the sub-panel placed as close as I can get it, to the most important room -- the Soundlab 2-channel one (which, it appears shorter runs from the panel to the room are very good things)!

Yep, Low Voltage CAT and COAX are another can that I opened and thankfully for it, I believe I have if figured out. 

Cable runs:  CAT 6 = 35; RG6 = 17, Conduit = 6 will pull strings for  anyplace that I may need to pull more low voltage cables); In-Room Speaker = 9; In-Room HDM1 = 9 and at least 1 Fiber from outside junction box to structured wiring cabinet. 

NOTE:  One of the low voltage quotes suggested putting the conduit in the attic:  The estimator's logic (based on experience; I would never have thought of it) follows: 
"For all the conduit runs that are in each location, my thought would be to cap them in the attic instead of running them all the way back to where the rack would be located."  "You'll have a conduit run (likely 2) going from the rack to the attic so it will be easy to feed all the way from location to demarcation."  "Running a conduit that whole way may provide hang-ups at some point so if we keep the conduit runs around 20' and as vertical as possible, that makes it that much easier."

Speaking of the attic, we're placing an over-the-air TV antenna there, in order to cut the darn cable.  It's about time!  Netflix, Prime, and streaming services like Hulu, and Direct TV NOW are allowing all to only pay for what they watch (rather than 10,000 channels of "krap") and it's streaming rather than time based.  What's not too like!! 

Walls are open, WiFi is fine, but is not as robust as wired, so why not string cable everywhere?

CAT and A/C for potential POI security cameras.  Presently, CAT is our friend from a hardwire perspective.

BTW, I plan on using ROON to stream to several of those CAT 6 locations, plus A/C for self powered speakers.

From an AudioCircle Thread: "I was given this advice from the design engineer of a well known Audiophile Power Conditioner manufacturer."
"Use round Romex 10/3 or 12/3. Inside are 4 wires, a black, white, red and bare wire(s). Use black for hot, white for neutral, the red and the bare are both for ground (using 2 wires for ground gives you a much lower impedance path to earth ground resulting in a quieter system with a lower noise floor). If you do 2 dedicated circuits, make the wire length identical for both if at all possible."

And another A/Circle post: "The 10/3 (plus ground) Romex® NMB is typically used for split phase 240V circuits. But the 3 conductor (+G) has a virtue when used in 120V circuits (one wire is not connected) that virtue is that it has a natural twist which reduces interference."

Al, I found the above. So, when you mentioned 12/3, it correlated with what others had said. So, perhaps 12/3 if installed, does have some benefit?

Hi Mike,

Twisted construction, as is apparently provided in the round Romex referred to in the AudioCircle posts you quoted, will reduce susceptibility to pickup of interference (RFI/EMI). However in a situation where interconnected components in a system are powered from different dedicated lines that potential benefit is, IMO, more likely than not to be outweighed by the importance of minimizing susceptibility to ground loop effects (which besides resulting in hum in some cases can result in high frequency buzz, reduction of "background blackness," and other such high frequency effects). And given what is said in the section of Mr. Whitlock’s paper that I cited, the symmetrical placement of the current carrying conductors in 12-2 + Ground flat Romex relative to the safety ground conductor will serve that goal better than the asymmetrical configuration that would result from paralleling the red wire with the ground wire, as suggested in the first of the AudioCircle posts that you quoted. And I suspect also better than the configuration suggested in the second post, given the unconnected wire in the cable and the unknown configuration and uniformity of the twist.

Best regards,
-- Al

@almarg,

Al, thank you for the kind words.

+1 on the information you gave mrmb. I would add 2 wire + ground MC (Metal Clad) aluminum armor cable has a lower "Ground Voltage Induction (GVI)" than 2 wire + ground NM-B sheathed cable does. (Romex  is a Trade Name of NM-B)

 Solid copper 10/2 with ground MC aluminum armor cable.
https://www.homedepot.com/p/Southwire-10-2-x-125-ft-Solid-CU-MC-Metal-Clad-Armorlite-Cable-69117005/...

Jim 

Thanks Jim:  To make sure I got it, the lower GVI of MC aluminum clad a negative and thus, supports Al's suggestion of using NM-B?

I'm still confused at to whether we should use NM-B vs. XHHW vs. THHN.  One of the differences of XHHW verses the other 2 is in the insulation.  XHHW's is Polyethylene; whereas NM-B and THHN is PVC.  One poster in another forum suggested that Polyethylene Insulation (& thus XHHW) may be better.  However, a quick search suggests that NM-B is the most prevalent and thus, should be what we recommend to our electrician -- i.e. Southwire Brand Romex NM-B.

Any experience with XHHW vs NM-B when used for audio?  My guess is that it would be difficult at best, to try to discern a sonic difference between the two (I hate auditioning audio cables; let alone Romex).  So why not just USE what's readily available (NM-B)?  Sound like a plan? 

Hi Mike,

No, Jim is saying that the cable he suggested would be an even better choice than my suggestion of Romex.  I have no reason to doubt that.

Best regards,
-- Al

@mrmb,

I am still working on a reply to your long posted message. You asked a lot of different questions.

In response to your last post.

Thanks Jim: To make sure I got it, the lower GVI of MC aluminum clad a negative and thus, supports Al’s suggestion of using NM-B?

No it’s a positive thing. The lower the GVI the better. With that said I would say the majority of dedicated branch circuits installed for audio equipment is NM-B cable using plastic rough-in wall outlet boxes though.

If you use NM-B cable for the audio/video dedicated branch circuits there are a few installation guidelines that should/must be followed.

I assume the house will not have a basement or crawl space. You said in a post the branch circuits will be installed above the ceiling joists/rafters/attic space area.

1) * Each NM-B cable needs to be installed separated by at least 12" from any other parallel run branch circuit wiring. More than 12" is better yet. If the parallel ran dedicated branch circuit cables are not kept separated from one another, as well as other parallel branch circuit wiring, the magnetic fields of the AC current carrying conductors can/will induce a voltage onto the equipment grounding conductors of the other cables. This can cause ground loop hum problems. The induced voltage can/will also transfer AC noise (EMI/RFI) from one cable to the other. Dedicated branch circuit NM-B cables must be kept separated from one another as soon as reasonably practicable after existing the electrical panel all the way to the drops down the wall stud cavity to the wall rough-in boxes. That includes keeping the dedicated circuits rough-in wall boxes separated from one another by at least 12" or more.

* * * EDIT:
 Depending on the location of the sub panel to the room, the dedicated branch circuits will be installed, it is possible the electrician could install the dedicated circuits entirely through individually separated bored holes in the wall studs. 

2) * MN-B cables should be installed at least 5ft from any ceiling lights / can lights where dimmers, or LED, or CFL lighting is used. That includes load side branch circuit wiring of the noisy harmonic producing items. The nasty, filthy, harmonics will infect the audio dedicated branch circuits if the electrician does not keep the audio dedicated branch circuits away.
https://www.youtube.com/watch?v=OCK5W9vlAE0

3) * Same goes for the sub panel feeder that will feed the sub panel. I assume the electrician will install a 3 wire + ground NM-B cable to feed the sub panel from one of the 200 amp electrical panels. Keep the feeder away from harmonic producing things like dimmers, LED and or CFL light fixtures. That includes load branch circuit wiring.

I’m still confused at to whether we should use NM-B vs. XHHW vs. THHN.

The insulated conductors used in NM-B sheath cable is THHN insulation.
http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet6

XHHW? Single insulated conductors pulled/installed in an empty conduit after the conduit is installed? Are you thinking of having conduit installed?

Any experience with XHHW vs NM-B when used for audio? My guess is that it would be difficult at best, to try to discern a sonic difference between the two (I hate auditioning audio cables; let alone Romex). So why not just USE what’s readily available (NM-B)? Sound like a plan?

XHHW is commonly used in industrial facilities where its’ add heat temperature rating is desired. Because of the tough insulation XHHW also has a high resistance to chafing due to vibration inside conduits, boxes, make up boxes for large motors, and such, where vibration may be a factor. XHHW insulation is tough as steel nails.
XHHW is also used in underground conduit runs for its’ added moisture/water protection properties. It will hold up better in hash environments far better than than THHN/THWN will.
Beats me how it would have any impact on the SQ of audio equipment though.

Here is a pro audio white paper for you to read through.
https://www.anixter.com/content/dam/Images/Logos/Supplier-Logos/Middle-Atlantic/PowerPaper.pdf

Jim

And the cable is? 

It looks like Jim prefers what he linked to:    Solid copper 10/2 with ground MC aluminum armor cable.
https://www.homedepot.com/p/Southwire-10-2-x-125-ft-Solid-CU-MC-Metal-Clad-Armorlite-Cable-69117005/...

Have I got it? 

Both the clad and un-clad seem to be the same price, so cost isn't an issue.

If indeed I got it right and clad (MC) is the choice, would that only be for the A/V areas that I want dedicated lines to, in the new house?  My total guess is that it would seem that unclad -- NM-B -- may be easier to work with for all the other pulls.  So, that means that MC will be used for my audio dedicated lines and NM-B will be used everywhere else? 

Re my 1:50 post:  Sorry Jim I jumped the gun.  I was working on this post while your above 1:48 post was in process.  

Jim said:   I assume the house will not have a basement or crawl space. You said in a post the branch circuits will be installed above the ceiling joists/rafters/attic space area.

The house does have a walk-out basement.  In fact, that is where 2 of the 3 audio/video rooms will be, with the most important one being my 2-channel Soundlab room.

Thanks Al and Jim.  For the uninitiated and untrained, this whole house wiring area as it applies to audio (and video) is a black hole of information.  So, while your comments are helping me, hopefully having them in one place like this, will do so for everyone who find this thread. 

@mrmb ,

Where to start.

Speaking of electrical noise/hum, I just found a Martin Logan article speaking about pre-wiring https://www.martinlogan.com/learn/faq-prewiring-a-home-theater.php.).

It addresses one of my other concerns about inserting multiple dedicated circuits in one room. They advise to connect all outlets/circuits with the same ground wire. I’ve previously read that ALL audio components should be connected together -- i.e., on the same dedicated circuit. If one didn’t tie 2-dedicated circuits together by using the same ground, I can see why I’ve seen that advice.

Electrical code says the safety equipment grounding conductor shall be part of, installed in, the cable with the current carrying branch circuit conductors.

I guess the electrician could tie all the equipment ground wires together with a bonding jumper at all the wall rough-in outlet boxes locations. You would need to ask him if he has a problem with it or if the AHJ, (Authority Having Jurisdiction), Electrical Inspector would have a problem with it.
I am pretty sure, depending on the State and city you live in, the electrician will install AFCI (Arc Fault Circuit Interrupter) breakers in the the load center panel that will feed the new dedicated branch circuits. Connecting all the equipment grounds together at outlet boxes could cause a problem. I don’t know, the electrician might know.
I personally do not see the need to bond all the equipment grounding conductors together at the wall outlet boxes, IF, the proper branch circuit wiring is used and the proper branch circuit wiring installation method is followed for audio/video branch circuit wiring.

Just a guess the electricians that will be wiring your new home are Residential Wiremen. They will follow, meet, the bare minimum electrical safety code required by NEC and the AHJ in your area. That is how the electrical contractor bids the job. You will need to spec and pay extra for any additional materials and wiring methods you want for the audio/video branch circuit wiring. Your wants must meet bare minimum electrical safety code standards for your area. You can exceed bare minimum electrical code standards all you want. It’s what ever you can afford.

My suggestions are based on NEC, (National Electrical Code), standards. The AHJ in your State and or local governing body has the final say.

The main electrical service.
Depending where you live, soil resistivity and severity of lightning storms, the earth connection of the electrical service is very important for lightning protection. In my area I highly doubt any residential electrical contractor checks the electrical service grounding electrode to earth resistance. They just supplement the required ground rod with a second ground rod. That meets the requirement of NEC.

IEEE recommends 5 ohms or less.
NEC says if the grounding electrode to earth resistance is greater than 25 ohms it shall be augmented by one additional ground rod. That’s it, no further testing is required.
https://en.wikipedia.org/wiki/Soil_resistivity

The test must be preformed by someone that has been trained and certified for use of the testing equipment used. I would suggest you hire a well established "Power Quality" testing company in your area. Most large Commercial/Industrial Electrical Contractors can recommend one to you. Price in my area runs around $150 to $200 for the testing. IF additional earth grounding is needed to achieve a ground rod to earth resistance of less than than 5 ohms you will have to pay an electrical contractor to install the additional earth grounding electrodes. Usually more 10ft earth driven ground rods is not the answer. In most cases a 30ft deep driven ground rod will do the job. (Three 5/8" X 10ft ground rods coupled together.) BUT it depends on the soil resistivity where you live.

I think I pretty much covered the rest of your questions in my last post.

I will add if you are going to install a sub panel feed it with at least #4 copper or #2 aluminum wire.

For audio equipment, system, connected together with wire interconnects it is recommended the dedicated branch circuits be fed from breakers fed from the same Line, Leg. All from Line 1 or all from Line 2, not from both though. In your case, If I read you posts correct, you have multiple A/V systems. You could balance the sub panel out by using line 1 for one system, connected together by wire interconnects, and the other system, connected together by interconnects, from Line 2.

If the electrician questions your directions, for feeding the dedicated circuits for each system from the same Line, just tell him the total connected continuous load is less than 16 amps. And the dedicated circuits are intended to be used to feed audio and video equipment only. That should satisfy him as well as the electrical inspector.

Speaking of the electrical inspector, there is a very good chance the electrical code in your area requires "Tamper Resistant" receptacles. Are your audio grade duplex receptacles Tamper Resistant? The electrician will have to install Tamper Resistant outlets for the final electrical inspection otherwise the inspector will Red Flag the job. Not to mention the inspector will chew out the electrician for installing non Tamper Resistant ones, wasting his time on a callback inspection.
I am not going to suggest what you can do after the final inspection an the occupancy permit has been issued.

Dedicated branch circuit wire size for the 2 channel audio equipment? I would install overkill and use #10awg solid copper wire. The breakers will be 20 amp making them 20 amp circuits. For the speakers I would install #12awg solid copper wire minimum, fed from a 20 amp branch circuit breaker.

Type of branch circuit wiring used?
If you choose NM-B use plastic boxes, not ferrous steel boxes. The electrician will use deep plastic boxes for the #10 solid wire. He will need all the room he can get for the #10 solid wire to make up on the duplex receptacle outlet. Ask the electrician to please connect the #10 solid wire to the side terminal screws, by curling the wire clockwise around under the screw head, instead of using the back wire terminal screw plate to secure the wire. The connection made under the screw head will remain tight even as the electrician pushes, forces, the duplex into the wall box to complete the installation.

What are you using for a duplex cover plate?
Avoid low grade stainless steel plates with ferrous materials. It will degrade the sound. Use a strong magnet to check for ferrous materials in the cover plate.

A cheap nylon unbreakable/flexible plate works just fine.

If you use MC cable make sure the electrician buys solid copper conductors and aluminum armor. Yes it can be bought with stranded wire conductors. The electrician would much rather work with stranded #10 wire instead of solid.

Problem with using MC cable is the type of wall rough-in boxes used. I am not a fan of steel ferrous boxes used for the duplex receptacle outlet.

For what it’s worth I installed two 20 amp dedicated circuits, using #10/2 with ground MN-B sheathed cable, that are around 75ft each in length from the electrical panel to the wall outlets for my two channel audio system. The system is dead quiet.

Jim

Wow, this is great information. 
Thanks, Jea48.
B

Wow Jim, GREAT response!!  Ask and ye shall receive.  Thanks so much for your recommendations.  It sure helps me provide specific instructions to the electrician; whether I fully understand the technical logic behind the instructions or not.  Wiring should begin in ~2 weeks.

Contrary to your assumption which would normally be correct, the electric company sub-contractor does have a significant commercial and industrial resume, in fact, it's greater than it's residential one.

The good news is that our builder doesn't skimp on labor or materials. The bad news is we're paying for that (grin).  So, (2)-200 amp panels plus (1)-100 amp sub-panel were included in the estimate.  The question for my electrician is whether the sub-panel should be 60-amp or 100-amp.  From the following A/A thread, it appears that too much "headroom" (i.e. 100 vs 60 amps etc.) could be a problem:

QUESTION FROM AN AUDIO ASYLUM THREAD:

Q.  Is there really any harm in too much headroom if it doesn't cost too much extra?

A. Actually, there can be. When a load center is installed the electrician will attempt to balance each leg in order to create a symmetrical load on the incoming service. The way this is done is to populate each leg with breakers that are evenly distributed, kind of like this:

Leg1 Leg2

50 60

30 30

20 20

20 20

20 15

20 15

15 20

15 20

15 15

15 15

If you run a subpanel, you will put the breaker on one leg. If you run individual lines, it's best to put them all on one leg. If you vastly oversize your setup (i.e. a 100A sub-panel), and then only use say 12A of that capacity, you'll be putting an asymmetric load on the legs. An extreme asymmetric load is bad - bad for your appliances, bad for your power bill.

My builder has already greased the skids with the electrician by telling him I would have some pretty unique needs.  In turn, via email, I sent the electrician a heads-up of some of my general needs, including links to my gear.  Next because of your help, I will document the specifics of what we're desiring and place notes for him on the pdf's of our house plans.

I really appreciate your comments about the breaker box wiring!!!  That was one area that had me stumped.  Especially because the sub-panel will be dedicated to JUST A/V type equipment. 

I suppose installing a sub-panel is prudent.  The box is fairly inexpensive and it will be placed closer to the 2-channel audio alcove and the adjacent entertainment/home theater area. These areas are combined in a "L" type configuration. Only extend the bottom leg of the "L" to look like the traditional perpendicular drawing. The audio room is at 1-end of that leg and a bar is at the other end; with the H/T room on the other end of the "L".

Fearing as you suggested, that the bare minimum would be provided, I was happy to read your suggestion of feeding "the sub-panel with at least #4 copper or #2 aluminum wire".  Speaking of same, do you find any value in doing the connection as I found someone advised on another forum by: 

“running one large wire from the very top position in the load center on the leg with the least number of noise-generating devices to a sub-panel”?

Lastly, if it means anything relative to your service grounding commentary, we're in Indiana.  
All the best,
-Mike

Did not see it mentioned, you want to make sure you buy main and sub panel that have copper buss bar, Square D QO , Siemens, cutler hammer.

I ran a Sub panel like you want to I used 0 THNN which was way oversize for a 100 sub, glad I did. You may want to also consider whole
 house surge protection, wires right into your main panel.

One last thought, a lot of folks on dedicated lines, incorporate Isolation
transformers.

Congrats on your new home! 

Wow, this is great information.
Thanks, Jea48.

+1.  Great info indeed.  Thanks, Jim!

Mike, I don't understand the AA post you quoted.  In the stated example it seems to me that if the load is unbalanced by 12 amps, it is unbalanced by 12 amps regardless of whether the sub-panel is a 60 amp panel or a 100 amp panel.

Best regards,
-- Al
 

Al, if you don't understand it, I'm not knowledgeable enough to speculate one way or the other.  It would take about 3-minutes of typing to describe what I know about the electricity subject. Here goes:  I can re-set a circuit breaker, screw-in a light bulb and on a good day, change out a switch or receptacle; but anything more, I'm flying blind.  Hence, why this whole topic is such a mystery.  I can't help but think that probably is the case for many.  Which is exactly the reason why I believe a thread like this has such value to anyone in my position.  Someone with virtually zero theoretical and practical knowledge about power distribution.  Which is what makes you and Jim's commentary so valued!

I inserted the AA post because I thought it may help someone in a similar circumstance.  Hopefully, our electrician will know how best to balance the load and not install something that would be over sized, or present an "asymmetric load" -- as the A/A poster said.  

From the AA post above:
If you run a subpanel, you will put the breaker on one leg. If you run individual lines, it’s best to put them all on one leg. If you vastly oversize your setup (i.e. a 100A sub-panel), and then only use say 12A of that capacity, you’ll be putting an asymmetric load on the legs. An extreme asymmetric load is bad - bad for your appliances, bad for your power bill.

almarg said:

Mike, I don’t understand the AA post you quoted. In the stated example it seems to me that if the load is unbalanced by 12 amps, it is unbalanced by 12 amps regardless of whether the sub-panel is a 60 amp panel or a 100 amp panel.

Best regards,
-- Al

+1

~ ~ ~

A 120V 12 amp load?

What if the 12 amp load was fed from a single branch circuit? What then?

120V loads are changing all the time.

Yes by code the electrician is supposed to balance the electrical panel connected 120V loads the best he can. But he doesn’t know what the home owner might plug into any given wall electrical outlet. How about a vacuum cleaner? Most draw 12 amps.

Sure he can balance the circuits above the counter tops in the kitchen. He can put the circuit that feeds the microwave on a breaker fed from say L1 and the Dishwasher circuit on a breaker fed from L2. If they are running at the same time the two loads are somewhat balanced. What if the dishwasher is running and the microwave is not? Or the microwave is being used but not the dishwasher? Like I said 120V loads are changing all the time. The electrician tries to balance the 120V loads the best he can for the what if....

What you don’t do is move all the know 120V loads like the microwave, dishwasher, garbage disposal, washing machine, refrigerator, deep freeze, sump pump, and any other motor load you can think of to one Line, leg, in the electrical panel, so the other Line, leg, can be used for an audio system that draws maybe 8 to 10 amps tops.

jea48 said:

For audio equipment, system, connected together with wire interconnects it is recommended the dedicated branch circuits be fed from breakers fed from the same Line, Leg. All from Line 1 or all from Line 2, not from both though. In your case, If I read you posts correct, you have multiple A/V systems. You could balance the sub panel out by using line 1 for one system, connected together by wire interconnects, and the other system, connected together by interconnects, from Line 2.

If the electrician questions your directions, for feeding the dedicated circuits for each system from the same Line, just tell him the total connected continuous load is less than 16 amps. And the dedicated circuits are intended to be used to feed audio and video equipment only. That should satisfy him as well as the electrical inspector.

The sub panel 120V loads will be somewhat balanced.
The same if the 2 ch audio room was fed with a single 120V 20 amp branch circuit connected to say L1 and the HT room was fed with another 120V 20 amp branch circuit fed from L2. What is the total connected load to L1? What is the total connected load to L2? What are the chances both systems will be in use at the same time?

~ ~ ~

@mrmb,

Have you considered what you will be insulating the wall stud spaces with in the audio and HT rooms? Sound type insulation?

What will you be covering the wall studs and ceiling joists with?

Dry wall, sheetrock, I assume?
How thick?
How many layers?
Type of glue used between layers?
Resilient channels installed on wall studs and ceiling joists?
Example of:
http://www.soundproofing.org/infopages/channel.htm

What ever you decide to do the electrician will need to know before he installs the outlet boxes.

Type of lighting in the rooms.


Jim

Very timely and prudent questions.  I was on the AVS Forum yesterday searching for what folks were doing to their dedicated H/T rooms.  All I saw pertained to  SOUNDPROOFING  -- i.e., stemming the sound between floors and rooms; which I really don't need.

HOWEVER, I am very interested in suggestions about the ACOUSTIC applications that could be done to enhance the 2-channel experience and the H/T one, since both rooms are connected/adjoining -- i.e., tricks or tips that could be installed BEFORE the drywall is installed?  

In the past I've read about installing extra layers of drywall, using glue etc., but wondered if that had any advantage other than soundproofing. Please by all means let me know what would make sense to do....   
 
While I was on AVS, I did find some good suggestions about isolating the projector from above the basement, main-floor vibrations; which was something I hadn't thought about -- a vibrating PJ is not a good thing, contrary to what she said (grin)!  So, I was pleased to learn that.

My area will be multi-functional.  That is, the H/T side won't look like a theater.  So, H/T equipment will be on a rack in front of the screen and speakers and subs won't be hidden etc.  I like seeing my toys too much, ha!  But I am considering installing can lights.  Any sonic precautions to take with these? 

Also because I saw so many instances on AVS, I did briefly consider having bulkheads installed in our 9' basement ceiling, but other than for aesthetics, I couldn't imagine what the sonic benefits would be!? 

On the other hand, I do take acoustics and sound absorption VERY seriously and will do whatever it takes to tame the area, moderate standing waves and inhibit reflections!!  But as I've done in our present house, that has been done after the drywall is installed. 

HOWEVER, if I'm missing something that COULD/SHOULD be done before the drywall, PLEASE let me know!! 

-Mike  

I wish Audiogon could make a 'Sticky' post, because I think this one is a great candidate.
Bob

To Jea48, Jim:  As previously noted above, Al deferred to your choice of Romex MC (Metal Clad) as opposed to his original choice of Romex NM-B, by saying that he had “no reason to doubt that”…MC..”was a better choice”. Well NOW, if you are BOTH suggesting MC -- winner, winner, chicken diner, that’s what I will definitely use!

Because it is determined that I will DEFINITELY be installing MC (and NOT NM-B), then how does it get installed -- as compared to your excellent description below (beginning with your below quote labeled #1 --  of how to properly install NM-B?

Jea48's, Jim's Quote: If you use NM-B cable for the audio/video dedicated branch circuits there are a few installation guidelines that should/must be followed.   

I assume the house will not have a basement or crawl space. You said in a post the branch circuits will be installed above the ceiling joists/rafters/attic space area.

Mrmb’s (Mike's) Reply Quote: That’s incorrect, the house does have a basement. In fact, the 2-channel audio room is in the basement along with a H/T area.

I'm unsure how the basement question correlated to your following installation description. So, assuming that your NM-B comments apply ONLY to an “above the ceiling joists/rafters/attic space area”. Then for others reading this thread, and they’re going to use NM-B, what would your instructions for them be – i.e., what would you add or delete from the below 3 bullet points, for those that DO have a basement and want to use NM-B?

Je48's, (Jim's) Quote: 

1) * Each NM-B cable needs to be installed separated by at least 12" from any other parallel run branch circuit wiring. More than 12" is better yet. If the parallel ran dedicated branch circuit cables are not kept separated from one another, as well as other parallel branch circuit wiring, the magnetic fields of the AC current carrying conductors can/will induce a voltage onto the equipment grounding conductors of the other cables. This can cause ground loop hum problems. The induced voltage can/will also transfer AC noise (EMI/RFI) from one cable to the other. Dedicated branch circuit NM-B cables must be kept separated from one another as soon as reasonably practicable after existing the electrical panel all the way to the drops down the wall stud cavity to the wall rough-in boxes. That includes keeping the dedicated circuits rough-in wall boxes separated from one another by at least 12" or more.

* * * EDIT:

 Depending on the location of the sub panel to the room, the dedicated branch circuits will be installed, it is possible the electrician could install the dedicated circuits entirely through individually separated bored holes in the wall studs.

2) * MN-B cables should be installed at least 5ft from any ceiling lights / can lights where dimmers, or LED, or CFL lighting is used. That includes load side branch circuit wiring of the noisy harmonic producing items. The nasty, filthy, harmonics will infect the audio dedicated branch circuits if the electrician does not keep the audio dedicated branch circuits away.

https://www.youtube.com/watch?v=OCK5W9vlAE0

3) * Same goes for the sub panel feeder that will feed the sub panel. I assume the electrician will install a 3 wire + ground NM-B cable to feed the sub panel from one of the 200 amp electrical panels. Keep the feeder away from harmonic producing things like dimmers, LED and or CFL light fixtures. That includes load branch circuit wiring.

So, now that you provided those fine 3 bullet points for installing Romex NM-B, but I’ve decided, based on your recommendation and Al’s concurrence to install Romex MC, what are your recommended bullet points for handling and installing Romex MC?  How do they differ from the above bullets?

And a 2nd. question is:  would you install MC ONLY for the dedicated CIRCUITS to be used for audio/video applications?  Is NM-B (as opposed to MC) the Romex usually installed in a residential situation?  Posed another way:  is there a reason either from a handling, installation or quality of use perspective, why MC shouldn’t be installed house-wide, or why the electrician may not want to install MC house-wide? 

Again thanks for your assistance Jim!

mrmb OP227 posts01-31-2018 9:47am

To Jea48, Jim:  As previously noted above, Al deferred to your choice of Romex MC (Metal Clad) as opposed to his original choice of Romex NM-B, by saying that he had “no reason to doubt that”…MC..”was a better choice”. Well NOW, if you are BOTH suggesting MC -- winner, winner, chicken diner, that’s what I will definitely use!

@mrmb,

I didn't recommend the use of MC cable over NM-B cable. I don't think Al, (almarg), did either.

As I said in one of my posts  I installed 10/2 with ground NM-B cable using plastic boxes for the two 120V 20 amp dedicated circuits for my 2 ch audio system.

I believe you said your 2ch and HT rooms will be located in the basement. I assume at least one of the 200 electrical panels will be installed in a mechanical room in the basement as well. I assume from that panel, the 100 amp sub panel will be fed from.
I assume the electrician will install the feeder wiring from the 200 amp panel, in the basement, to feed the sub panel through bored holes in the above engineered I floor joists, or trussed floored joists, above. The electrician, I assume, will also install the dedicated branch circuits wiring for the 2ch audio room and HT room from the sub panel. Either through the above floor joists or basement wall studs. Just make sure he keeps them from the ceiling can lights and load side branch circuit wiring of the can lights for reasons I stated in an above post.

@mrmb ,

You might want to contact your builder and ask him if he would call the electrical contractor and schedule a meeting where you can meet with the contractor, or his representative, so you can address your concerns. The fact that you said the electrical contractor’s main business is commercial and industrial is a good thing. That does not mean the electricians that will be wiring your new house will be Inside Wiremen and not Residential Wiremen. (Pay grade is a lot less for a residential wiremen.) It’s not unusual for a contractor to employ both inside wiremen and residential wiremen. Not to mention residential wiremen are trained how to wire houses fast.

Make sure at least one of the electrical contractor’s representatives you meet with is a State Licensed Master Electrician. He/she will have a better understanding of your concerns. Instructions will be given to the electricians who will be wiring your two audio/video rooms.

It is a lot cheaper to layout the job on paper beforehand than to make changes after the job starts. Change orders can be/are expensive.

If you have not watched the Cary Grant movie, " Mr. Blandings Builds His Dream House", I highly recommend you watch it.
https://en.wikipedia.org/wiki/Mr._Blandings_Builds_His_Dream_House

Jim

jea48 (Jim):  Gesh -- forehead-slap -- reading one thing and assuming another, I apologize for my MC misinterpretation and confounding the issue!!  You patience is appreciated!

Although we've had 2 custom houses built previously, I seem to have spaced (as I did with the MC, NM-B issue) the hurry-up-to-wait process.  When the builder told us that wiring should start soon, I thought jeez, although I had compiled lots of data, I didn't have a summary of same or conclusions to tell the electrician.  You corrected that concern with your cogent and thoughtful replies. 

I will indeed use your advice when meeting with the electrician.  Hopefully, it will go well, but Murphy's Law is ever-present. 

I'm dealing with the Low Voltage estimates presently.  Fortunately I'm much more attuned to the ramifications of what was needed to be spec'ed. with CAT6, Q/S-RG6 and fiber.  Especially how CAT6 should be kept separate from the Romax, much like you explained about with the minimum 12" separation of the individual parallell branch circuits.  I'm sure that sort of spacing isn't something most electricians or low voltage technicans get overly concerned with, unless they're required to....

The "Mr. Blanding's Builds His Dream Home" with Cary Grant is indeed a classic.  What a FUBAR position he found himself in.  Sorta' like the beginning of "Green Acres" when Mr. Douglas (Eddie Albert) bought his farm house.  Thanks for the grin with the mention of Mr. Blandings.  Cary's movies are some of my favorites, as are his co-star's, Myrna Loy in the "Thin Man" series with William Powell.   Humorous memories.... 
 
Thanks again, Mike.

I defer to both Almarg and Jea, so if either contradicts me, please accept that view.

Consider an isolation transformer. I use one on every audio circuit, all of them grounded to to a common copper pipe, which is soldered to house ground (and paralleled to the oversized copper water line).

But, isolation transformers do growl when they are doing their job, so it is important to site them outside the listening room.

I also use braided shielding for power lines which are not metal clad, like DC power cords, especially near signal lines. As a result, my system is black.

Also, you might want to consider sand in the walls. This makes the walls hard to move, because they are heavy, and to not ring because they are dead. There is more than a ton of sand in my ceiling.

@terry9 .
God forbid you ever have a leak ;)
B

Thanks Bob. Thought I'd help Him out though - it's industrial grade copper.

Good unique suggestions terry9.  They're accepted even before a contradiction.  Was you experience a jaw dropping one when you first heard your system with "braided shielding for power lines"?   

Multi-function tweaks, what's not to like? Room resonance damping and fire protection all rolled into one (the 'ole sand on the fire trick). I wonder though, which color of sand works best for both purposes: brown, white, black, some combination, or with the additive of equal parts of snake oil and bull manure?     


  

mrmb said:

I’m dealing with the Low Voltage estimates presently. Fortunately I’m much more attuned to the ramifications of what was needed to be spec’ed. with CAT6, Q/S-RG6 and fiber. Especially how CAT6 should be kept separate from the Romax, much like you explained about with the minimum 12" separation of the individual parallell branch circuits. I’m sure that sort of spacing isn’t something most electricians or low voltage technicans get overly concerned with, unless they’re required to....

Not all low voltage cable installers are created equal.
Did you ask the electrical contractor who he uses?

Make sure the Communication Company you hire will supply you with a copy of a certification test report for each data cable installed. Also the person testing the cabling, from the Patch Panel to wall jack, must be certified for the test equipment used.
Here is some reading info.
http://www.informit.com/articles/article.aspx?p=1403240&seqNum=3

Here, for an example, is a video showing an Ideal scanner cable tester.
Go to time mark 7:50 to see what’s involved in testing a 4 pair Lan data cable.
https://www.youtube.com/watch?v=wn-EsoD-FnQ

What manufacture of cable CAT6 cable will be used?

What manufacture of CAT6 Patch Panel/jacks and wall jacks?
I like Panduit. A little more pricey than the competition. Pair twist is maintained right up to the terminations. Same jack plugs into their Patch panel plate.
http://www1.panduit.com/en/products-and-services/products/safety-and-security/physical-network-secur...

Jim

The biggest effect was isolation transformers. After installation, I compared different power cords as well as premium power conditioners on standard outlets, against the transformers, and nothing came close. But they do growl.

Plitron makes a good one, and they sell direct to the public. The medical isolation transformers are best.

I used braided shielding from a rack mounted central power supply on all my DC power cords as a default, so I cannot say with certainty, that they made much difference. I like to add what may be tiny incremental improvements where they can do no harm. Note that an amplifier is essentially a power supply modulator, so clean power is important.

Fire protection was also on my list of benefits - the gas furnace is adjacent. And it's noise stays out too. By all means make it into adobe - let us know how it works out.

jea48 (Jim) Not all low voltage cable installers are created equal.
Did you ask the electrical contractor who he uses?

A quote was obtained by whom our custom builder uses and I obtained one from a locally quite well reviewed (over 300 samples) installer. However he is sourcing cable from SnapAv were reluctant to tell him, but claimed to source Liberty CAT6. 

However, I wasn't too enamored with his insertion of a 23" $900 cabinet. Probably double its street price. Plus, he included labor to install the cabinet and its contents.  Charge double for components and lob labor onto doing so --  good if you can get it!  Yeah, I have ~36 CAT pulls.  But Lutron and Tripp-Lite make an open rack for a fraction of the enclosed cabinet quoted.  Bottom line:  I'm still negotiating with the installer. 

I will keep your other comments and suggestions in mind.

Cabinet?

What all will be installed installed in the cabinet?

Patch panel
+
?
?

RACK & NETWORK COMPONENTS:
1) WP-ONE-ENCL-28: Wirepath 28" Enclosure WP-ONE-DOOR-28: 2) Wirepatch 28" Venting Door SR-WMS-16U:
3) Strong Brands 16U Hinged Wall Rack w/ Door FK-120-4:
4) Cool Components 4-Zone Fan Kit WP-CAT6-PP-48:
5) Wirepath 48-Port CAT6 Patch Panel AN-110-SW-F-24:
6) Araknis Networks 24-Port Front-Side Switch AN-110-SW-F-16:
7) Araknis Networks 16-Port Front-Side Switch
With #3 at $900, the total with everything else is: $2142.80.

For example the 48-port patch panel (#5) was priced at: $228. A Cable-Matters one on Amazon is $58.99 (https://www.amazon.com/Cable-Matters-Rackmount-Wallmount-48-Port/dp/B0072K1P8C). Keep in mind, additional to the hardware costs, labor was applied to the quote to mount and install the stuff in the amount of $950 -- total for all of the above:  $3,092!!!

We managed to get by in our present house with a plastic phone type patch panel which was nailed by our electrician to the 2x4's 17-years ago for phone use; before we began using our CAT5e cabling for LAN use.  All has been well! Now you probably wouldn’t want to check the system’s speed, but other than streaming music with ROON, surfing the www and streaming Netflix, we have no mission critical needs requiring $3K worth of labor and hardware – fans, coolers, UPS, a halon fire extinguishing system and a partridge in a pear tree!!

Our RG6 cable home runs were left hanging in the air connected to spliters.

Our LAN and COAX systems are as inelegant as they can get. But for a buck-ninty-eight vs $3,000, I will take the former any day. If I were doing it myself, which I physically can't, rather than $900 for a cabinet, I would nail shelves between the basement's 2x4's or install peg board to mount the components. Well probably not, but an open rack mounted between the studs, should work quite nicely and for 90% less $.

The funny thing is this guy’s cable pulling labor was not outlandish and without crunching the numbers, significantly less than another Low Voltage guy’s quote, go figure. Lots of fun….

@jea48 said: "If you have not watched the Cary Grant movie, " Mr. Blandings Builds His Dream House", I highly recommend you watch it."

The painter scene is a classic. Kind of sums up a lot about the nuances of obsession translated into contractor-ese. Priceless.

@whart ,

LOL, This one?
https://www.youtube.com/watch?v=s33ScN4D-HU

How about this scene?
https://www.youtube.com/watch?v=05WhNMT8FWE

Jim

When dealing with large systems getting enough circuits is very important. Figure one 20 amp circuit, terminated in a duplex outlet per power amplifier or powered speaker. Hospital quality plugs also are worth the investment. A 20 amp circuit can handle most amplifiers up to 600 watts total power. Have the electrician run 10 gauge wire if you can afford it, and it is allowed by code. Also plan on at least one 20 amp circuit for your analog sources, and one for your digital sources. You should also have a separate circuit for your video components and displays. And one for your control system, if you will be using something like Control 4 or Crestron.

The video and control circuits should be wired to one phase of the breaker box, and the audio components to the other phase. Power strips and "outlet bars" do a very good job of keeping the grounds on the same plain to help eliminate any ground loops that cause hum. You are planning on having three separate systems, so you will need a lay out for each system.

Run at least 2 CAT 6 or 7 for control to each room, and two per video display. Shielded wire is always preferred for low voltage wires except speaker wires. If you have runs over 200 feet, consider fiber, it is very expensive, but worth it. If you plan on going to 4K video or 8K when it comes around in a few years, run wire with enough bandwidth now!!! 4K video will need at least a 10 gig network, and 8K is looking like it will need 50 gig. Wire is relatively cheap and easy to run when the walls are not covered yet. 

Also run a CAT 6 or 7 to each light switch, each of your appliances and your thermostat so you can wire them into your LAN. Computers, printers and phones should also be planned out. Wired is always preferred over wireless. You will probably need a LAN port for each component eventually when you figure out how many ports you want for your network switch. I will not even guess what you will need for your security system. 

People above have already mentioned keep distance between 120v and low voltage wires. If they need to cross, 90 degrees is preferred.

@jea48 - the first clip was the one I was referring to but it’s been so long since I’ve watched the film. Myrna Loy was great.

Buy this:
Ideal, 61-164 SureTest Circuit Analyzer

It will show you voltage drop.

I installed a dedicated 20 amp circuit using a 10 wire with extra shielding. I also added a 2nd grounding rod. 

Your electrician won't likely have seen an analyzer like this one. 

Don't use cheap plugs and switches in your house. I used an AQ Energy plug, which is probably overkill, but it accommodated the 10 wire. For all other plugs, I pay about $5 each for the professional ones at Home Depot. These plugs have a strong grip.

Mrmb/Mike:

i wonder if an electrician would install 3 circuits with a common ground?  With 2 circuits from vertically adjacent panel slots the hots would be out of phase - okay for a ground of the same wire gauge.  3 circuits would put 2 in phase.  Perhaps, one could use 12 gauge for the hots and 8 for the neutral?  Ask...  Also why not use conduit?  You could pull and replace wires to your heart’s content.

hig3: Also plan on at least one 20 amp circuit for your analog sources, and one for your digital sources. You should also have a separate circuit for your video components and displays. And one for your control system, if you will be using something like Control 4 or Crestron.

After just deciding to install a 120" projection system adjacent to the 2-channel Soundlab room your suggestions help to decide how to managed the dedicated circuits.  Having all 

Quote: hig3: Also plan on at least one 20 amp circuit for your analog sources, and one for your digital sources. You should also have a separate circuit for your video components and displays. And one for your control system, if you will be using something like Control 4   Crestron.

After just deciding to install a 120" projection system adjacent to the 2-channel Soundlab room, your suggestions help to decide how to manage the dedicated circuits. Having all -- Oops, I accidently prematurely hit the post buttton -- so I will continue:
As was previously mentioned, my primary reason for a sub-panel was to shorten -- as much as possible -- the run from the load panel to my ALL important 2-channel room.  A real ancillary benefit is having a dedicated sub-load panel for all flat panel TV's (3), Surround Sound systems (2) and the dedicated Soundlab based 2-channel room (1). That makes managing my menagerie of dedicated circuits easier. 

It also takes the concern off the table, of keeping appliance motors, dimmers and other nasty's on the different panel position/legs/phase, and at bay.  

Quote: Hig3: Have the electrician run 10 gauge wire if you can afford it, and it is allowed by code…

After finding the aforementioned and linked to MSB article (http://www.msbtechnology.com/faq/how-to-wire-your-house-for-good-power/) ; I decided to run 10 gauge to all A/V locations.

Quote Hig3: The video and control circuits should be wired to one phase of the breaker box, and the audio components to the other phase. Power strips and "outlet bars" do a very good job of keeping the grounds on the same plain to help eliminate any ground loops that cause hum. You are planning on having three separate systems, so you will need a lay out for each system.

In this context, do the terms “phase” and “leg” mean the same? I’ve seen them used interchangeably?

Quote Ottuso: i wonder if an electrician would install 3 circuits with a common ground?  With 2 circuits from vertically adjacent panel slots the hots would be out of phase - okay for a ground of the same wire gauge.  3 circuits would put 2 in phase.  Perhaps, one could use 12 *[EDIT: 10] gauge for the hots and 8 for the neutral?  Ask...  

Being ignorant in panel wiring techniques, I would have to show your quote to the electrician, because for my knowledge base (or lack there of), the logic is confounding.   But after I show your paragraph to the electrician, he and I can discuss it. Thanks for that!!!

Because I haven't a clue, I wonder if your – at the panel suggestion addresses the single ground discussion (I had above with AlMarg? ) and the difficulty addressing it in a situation where ganged outlets are several, have some distance between them and multiple dedicated circuits are involved?

Quote Mrmb to AlMarg:  “Speaking of electrical noise/hum, I just found a Martin Logan article speaking about pre-wiring https://www.martinlogan.com/learn/faq-prewiring-a-home-theater.php.).”

“It addresses one of my other concerns about inserting multiple dedicated circuits in one room. They advise to connect all outlets/circuits with the same ground wire. I've previously read that ALL audio components should be connected together -- i.e., on the same dedicated circuit. If one didn't tie 2-dedicated circuits together by using the same ground, I can see why I've seen that advice.”

AlMarg: ”  1)As you appear to realize, the benefit of the single ground wire approach they advise is that it would minimize or eliminate any differences of potential (i.e., voltage) between the safety ground connections of the outlets for the various dedicated lines, and hence any differences in potential between the chassis of components that are interconnected in the same system but are powered by separate dedicated lines. Which in turn will avoid ground loop issues that might otherwise occur.

 2)If the electrician indicates that such an approach would be problematical, due to either practical considerations or code compliance issues, using 3-conductor Romex (e.g., 12-2 with ground) for each of the dedicated lines should come close to accomplishing the same thing. And could very conceivably provide results that are just as good.

 In 3-conductor Romex the safety ground wire is symmetrically placed between the hot and neutral conductors. Therefore voltages that may be induced into the safety ground conductor by the magnetic fields surrounding each of the two current carrying conductors [current flow in a conductor produces a magnetic field around that conductor] will tend to cancel, since the fields produced by the two current carrying conductors are in opposite directions.

For further explanation see pages 31 to 35 of the following paper, which was written by a renowned authority on such matters:

https://centralindianaaes.files.wordpress.com/2012/09/indy-aes-2012-seminar-w-notes-v1-0.pdf

Quote Ottuso: Also why not use conduit?  You could pull and replace wires to your heart’s content.

Yes, when building, Conduit is your BFF!!  One of the few things that I believe I have covered! 

 Always consider Conduit NOT ONLY for future mains pulls, but also low voltage pulls. The mains concern -- rather than the need to later add a different gauge or romex configuration – in my mind, derives from the future transition to fiber. 

Speaking of same, I was surprised to recently learn that the fiber cable itself, was competitive, if not cheaper than copper. However, one must add-in the cost of the Fiber Media Converters (10/100, as well as Gigabit) that enable one to convert Ethernet network connection to a fiber network connection and vice versa.

Quote Hig3:

“Also run a CAT 6 or 7 to each light switch, each of your appliances and your thermostat so you can wire them into your LAN. Computers, printers and phones should also be planned out. Wired is always preferred over wireless. You will probably need a LAN port for each component eventually when you figure out how many ports you want for your network switch. I will not even guess what you will need for your security system.”

Wow, perhaps light switches, but then I wonder if there any switches presently made with Ethernet connections so they can be inserted into the LAN? Perhaps so (I don’t know), in a professionally installed “smart” system? One, that as a DIY fan, I’m not interested in. Because I believe these professional installed systems are usually only installed and serviced by trained technicians – the only ones that are allowed to purchase and resell them. Being the cheapskate that I am, I would shy away from those.  I know....I know, in some instances, and for some folks, the benefits outweigh the cost.  

Nevertheless, that’s why WiFi enabled light devices (and in some cases many different ones and manufacture’s are compatitable), are such good things for DIY’ers. 

Although granted, WiFi is not as robust as hard-wired. However, WiFi is changing the home automation game for DIY’ers in a really big way!  

Moreover, I’m not sure I want to, or need to live with “smart” appliances and thermostats. Personally, lighting and perhaps security systems are the only automation systems that I’m presently interested in.  As always, and with everything else in life, that could change...

Quote Hig3: “People above have already mentioned keep distance between 120v and low voltage wires. If they need to cross, 90 degrees is preferred.”

Also as this thread has uncovered, each A/V critical Dedicated mains wire, needs to be handled in a similar fashion. 

Quote Per Jea48 (Jim):

“Each NM-B cable needs to be installed separated by at least 12" from any other parallel run branch circuit wiring. More than 12" is better yet. If the parallel ran dedicated branch circuit cables are not kept separated from one another, as well as other parallel branch circuit wiring, the magnetic fields of the AC current carrying conductors can/will induce a voltage onto the equipment grounding conductors of the other cables. This can cause ground loop hum problems. The induced voltage can/will also transfer AC noise (EMI/RFI) from one cable to the other. Dedicated branch circuit NM-B cables must be kept separated from one another as soon as reasonably practicable after existing the electrical panel all the way to the drops down the wall stud cavity to the wall rough-in boxes. That includes keeping the dedicated circuits rough-in wall boxes separated from one another by at least 12" or more.

* * * EDIT:

 Depending on the location of the sub panel to the room, the dedicated branch circuits will be installed, it is possible the electrician could install the dedicated circuits entirely through individually separated bored holes in the wall studs.

2) * MN-B cables should be installed at least 5ft from any ceiling lights / can lights where dimmers, or LED, or CFL lighting is used. That includes load side branch circuit wiring of the noisy harmonic producing items. The nasty, filthy, harmonics will infect the audio dedicated branch circuits if the electrician does not keep the audio dedicated branch circuits away.

https://www.youtube.com/watch?v=OCK5W9vlAE0

3) * Same goes for the sub panel feeder that will feed the sub panel. I assume the electrician will install a 3 wire + ground NM-B cable to feed the sub panel from one of the 200 amp electrical panels. Keep the feeder away from harmonic producing things like dimmers, LED and or CFL light fixtures. That includes load branch circuit wiring. 

AudioBill1 Quote: Buy this:

Ideal, 61-164 SureTest Circuit Analyzer EDIT to add Mfg. Link: [http://www.idealindustries.ca/products/test_measurement/circuit_analyzers/suretest_circuit_analyzers...]

It will show you voltage drop.

Your electrician won't likely have seen an analyzer like this one.

Interesting.....

I mentioned "ganged outlets" in the above post.  I believe -- with "believe" in quotes -- I understand the term. 

If a dedicated line is involved, "ganged outlets" means several outlets (receptacles) connected to that one dedicated line.  Have I kinda' got it?  If so, does that mean that the dedicated line would go back to a single phase or leg of the load panel?  If so, this then would define it as a "dedicated" line?

And if we're NOT dealing with a dedicated line, multiple outlets in many different locations could be ran off any one leg/phase of the panel?  With equally as many "ganged" outlets (as the load would permit) from the same leg/phase, because they are all emanating from the same load panel leg/phase?  

Man, if any, or all of this is remotely correct, I would be surprised.

If I have some or part of it correct, how many ganged outlets should be/could be ran from a dedicated circuit?  I suppose that depends upon the circuit's amperage and any resulting load would need to be estimated to determine that answer?  Nevertheless, for our audio/video needs, what would be an average &/or maximum number of outlets (before a too negative voltage drop were encountered) that could ran/connected from one dedicated circuit?

One dedicated 20 amp @ 120 volt circuit is all you need for your sound system. In fact it would likely sound better under certain circumstances vs multiple circuits. For fun, you can ask the electrician to use 30 amp #10-3 wire vs the standard 20 amp #12 wire.

Have to agree with fisher_400 here, as after moving in to our recently completed house, I saw the need for a dedicated 20A circuit for our “entertainment centre”, which housed telly and all the stereo gear, incl. powered sub.  Installed a 20A breaker in service panel, then ran 12/2 w/grnd. Romex cable, and parallel-wired via junction box to two commercial-grade 20A receptacles, and have enjoyed clean, noise-free operation ever since.  Also of note, I did install an isolated-ground, dedicated 15A circuit for home office use to support PC, printer, and telecom/network  peripherals, with hospital-grade duplex receptacle plus power bar...never had any adverse effects following repeated power outages, electrical storms, etc.  However, would be overkill for hi-fi equipment support, IMHO.