[iowa]

Hi all,

First off, apologies for all of the questions.

I am building a new home and am about to do the pre-drywall walkthrough. My plan is to have 2 dedicated 20A circuits run into 2 different listening spaces (2 in listening room and 2 in family room). What specs do I need to share with the builder/electrical contractor? I think I need in each space:

2 dedicated 20A circuits
12 gauge Romex
Use a separate ground for the dedicated circuits

Does this look right? Can all 4 circuits use the same dedicated ground? Is there anything else that I am missing? Is there a downside to having 2 receptacles/boxes on 1 circuit (so I could have dedicated outlets on 2 walls in each space)? I have ordered PS Audio Powerplus Classic outlets. Any other recommendations at or near that price point?

[mikeeastman]

I'd use 10 gauge romex instead. How are you planning to connect the separate grounds?

[ric]

This is not my area, but from what I've read/seen, some are using 10ga wire to feed their dedicated circuits. Some also say not to separate grounding devices, as they may cause more harm than good.
Perhaps consult with an acoustician about the size and shape of the room, and perhaps put material into the walls, or pre plan "cavities" that will serve as bass traps.
Also, plan your electronic layout, speakers, amps, etc. in advance, as well as seating. Find a good consultant!

[iowa]

"I'd use 10 gauge romex instead. How are you planning to connect the separate grounds?"
10 gauge-noted. No idea on the grounding. What do I need to know?

[iowa]

"This is not my area, but from what I've read/seen, some are using 10ga wire to feed their dedicated circuits. Some also say not to separate grounding devices, as they may cause more harm than good.
Perhaps consult with an acoustician about the size and shape of the room, and perhaps put material into the walls, or pre plan "cavities" that will serve as bass traps.
Also, plan your electronic layout, speakers, amps, etc. in advance, as well as seating. Find a good consultant!"

This is a low buck deal, so no $$ for a consultant. It is a small, square room so will be utilizing GIK Acoustics and may have to invest in a DIRAC, RoomPerfect, etc...hardware solution.

[twitch54]

20 amp service - check
10 ga wire -------check
 
Another suggestion is isolate your 'audio circuits' on one down leg in breaker panel and have your electrician try and keep circuits that will be 'dirty' (dimmer lights, appliances, etc) on the other down leg.

[Speedskater]

a] use Southwire brand Romex®
b] 20 Amp circuit to each room.
c] 10 AWG Romex® to a junction box in/near the room then break-out (10 or 12AWG) to the outlet boxes.
d] use top shelf industrial/commercial dual receptacles.
e] never ever mess with the Safety Ground (EGC) wiring. It needs to connect to the Neutral in the main breaker panel.
f] the connection to Planet Earth.  Just do whatever makes the electrician and the inspector happy. It's not of our concern.

[Rusty Jefferson]

Unless you're installing an unusually large capacity system there's no need for 10 gauge wire on your circuits. 2 dedicated 20 amp circuits will easily handle a normal home stereo. 10 gauge wire is more than twice the cost of 12 gauge.  Depending on how far away the panel is you could drop $1000 just on the wire for these rooms. Be sure your receptacles can handle 10 gauge if you decide to use it, but look at your gear and see what's needed. Unless you're using 200 watt class A mono-blocks......

If you're this concerned with good sound in the room(s) then move away from a square space.  Almost no chance of getting exceptional sound in a square room.

[Speedskater]

While copper prices have doubled in the last year, 100 feet of 12AWG Romex is $100 and 10AWG is $210.
And while no 10AWG is not needed, it's cost will be very small compared to the total electrical bill.
All quality dual 15 or 20A receptacles are listed for 10AWG.

[Delta77]

I have only a small amount of experience (1 time) trying out a dedicated line for stereo..
Had an electrician install a single run of solid 10 awg romex from the panel to a J-Box then split the line to three Duplexes in the stereo room..
The romex and Breaker was just standard equipment ( not Audiophile) , But all 3 duplexes are (P.I. Audio Group) Uberpuerto..
And that's it..
 
It's connected as follows.
The 2 outlets in the corners are plugged into the subs, one outlet for each sub..
the middle outlet is plugged into a (P.I. Audio Group) Uberbuss, which powers all of the electronics (Apple TV, Server, Dac, power supply for DAC, Preamp, Amp)..

Works great I did notice that my SS amp had a ground loop I couldn't get rid of , but after installing the dedicated line No Ground Loop Noise in my SS amp anymore..

If I were to do it again , I would install 2 Dedicated lines 1 for digital equipment and 1 for Analog equipment, Maybe a Audiophile Romex and Breaker..
(advise I had gotten from others here on AudioCircle)..

Just sharing my little bit of experience with dedicated lines..

                  BURT....

[iowa]

Thanks for the responses all
Another suggestion is isolate your 'audio circuits' on one down leg in breaker panel and have your electrician try and keep circuits that will be 'dirty' (dimmer lights, appliances, etc) on the other down leg.
Thanks, I should be able to do that.
10 AWG Romex® to a junction box in/near the room then break-out (10 or 12AWG) to the outlet boxes.
What is the benefit to a junction box rather than just running each circuit in series?
If you're this concerned with good sound in the room(s) then move away from a square space.  Almost no chance of getting exceptional sound in a square room.
I wish I had another option. I am moving my parent in and the small (11' x11' ) square room is the only space available for now. I understand I probably won't get exceptional sound. I am just hoping for good. I am running dedicated lines to the family room for when it will no longer the parents living room.

[rollo]

  May I suggest a sub-panel off the main panel using Siemens breakers for your dedicated lines. I would run lines directly to the duplex outlet to avoid more connections. Engineering wise good advice here. However hands on experience suggests 10ga [ I use 8ga ] for Amp line or lines and 12ga for analog and Digital. Very important to use separate lines for analog and digital in our experience. Have fun.


charles

[jtwrace]

c] 10 AWG Romex® to a junction box in/near the room then break-out (10 or 12AWG) to the outlet boxes.

This does not typically meet code.  If you run a 10AWG from the breaker the rest of the wire connected to that circuit needs to be the same or larger gauge.  However, if it's 12AWG from the breaker, you can use 10AWG from the first outlet to the next few.  One still needs to not overload the amount of outlets for that given circuit though.  Which IIRC, is 8 for 15A. 

[Housteau]

My sub panel is fed by 220V for the central AC.  My room is a small structure separate from the house, but connected to the roof by a covered walkway.  That is so both can be covered under the same insurance policy.  The audio circuits from that sub panel first feed a 5KVA 220/110V industrial instrumentation isolation transformer, then go to a smaller breaker box that feeds the outlets.  I added in the transformer basically because the cost was so very minimal by audiophile standards.  There is the ability to use two separate legs of 110V where one could be dedicated to analog and the other digital. 

[richidoo]

Use a separate ground for the dedicated circuits

Electrician dogma requires 20A circuit use 12ga wire. Good luck getting them to use 10ga especially if there's an inspection involved. But yes, it's legal and no, it won't make as big a difference as using JPS romex or even better using a power regenerator.

A dedicated circuit implies a separate ground from the single outlet to the service panel, using the ground conductor in the romex. If you add another outlet to the circuit then it's not a dedicated circuit anymore, it's shared, and both outlets will use the same ground back to the panel. This is fine if the connections are done correctly. Poor connections made by the builder electrician is a big problem. Two true dedicated circuits will require two separate lengths of romex back to the panel. This also violates electrician dogma and they will be hesitant to do it because it looks wasteful and stupid to the inspector. But it's legal of course.

If by "separate ground" you mean an additional earthing rod for audio system only, that technically does not meet the national electrical code. A building can only have one earthing rod for the sake of preventing a fire in case of a lightning strike.

On the subject of grounding, any external cables like cable TV or sat/FM antenna should use a lightning block where it enters the building so the ground wire can continue outside the building to bond directly to the earthing rod. Few installers know this, much less do it so you have to do it yourself. Grounding external signal cables correctly will probably cause a ground loop hum in your stereo, which you can defeat with a Jensen inline filter.

No matter how great the wire or using a dedicated line, the utility signal will still have clipping distortion (1-3% THD) because appliances that rectify the line to DC (electronics) only draw current at the voltage peaks. Only a power regenerator can fix that by regenerating the power from DC. It's a bigger improvement than a dedicated line, imo.
Good luck with your project!

[Housteau]

Only a power regenerator can fix that by regenerating the power from DC. It's a bigger improvement than a dedicated line, imo.
Good luck with your project!

Agreed and I would have done that myself if I had known more about them at the time.  Do you know of any industrial types that could service the entire circuit as my isolation one does at a reasonable price.  I am familiar with the audiophile ones for in room by PS Audio.

[emailtim]

FWIW, I went with 4 dedicated 20-amp audio circuits run in 10 gauge to the listening room.  10 gauge was in part due to the distance from the circuit breaker box.  The HT room has a 240V 5KVA Equi=Tech (shelf/rack) balanced power unit.

Equi=Tech used to sell balanced power breaker boxes for "technical power" applications in recording studios and high end home systems.  Equi=Tech was responsible for amendments to the NEC to provision for "technical power" in the late nineties if memory serves.  They aren't cheap.

http://www.6moons.com/audioreviews/equitech/1.html

[Big Red Machine]

Insulate your walls now. Even batt insulation helps keep room to room noise down some. I've done this in other homes and was glad I did. And insulate your toilet plumbing in the 2nd floor joists so you don't hear when someone flushes upstairs!

Not sure why folks want 2 lines. That means 2 power conditioners later on

[emailtim]

... Not sure why folks want 2 lines. That means 2 power conditioners later on

So each amp can have their own dedicated power line or an amp on one line and components on the other.  Much cheaper to add the extra circuit(s) while the walls are open than afterwards.

Many amp manufacturers discourage having power conditioners in front of their amps. 

With the entry of energy efficient SMPS amps (vs inefficient Class A amps), load requirements are less, but KW amps are still prevalent (2 - ICEPower ASP1000 monoblocks and a 20amp circuit is full).

[Speedskater]

This does not typically meet code.  If you run a 10AWG from the breaker the rest of the wire connected to that circuit needs to be the same or larger gauge.  However, if it's 12AWG from the breaker, you can use 10AWG from the first outlet to the next few.  One still needs to not overload the amount of outlets for that given circuit though.  Which IIRC, is 8 for 15A. 

This post is totally incorrect.
You can use any permitted AWG sized cables in any order in a circuit.
For instance.   In a 15Amp circuit: 10AWG>>14AWG>>12AWG
The max number of permitted receptacles on a circuit only applies to commercial installations.