Building New House - dedicated ele. best practices

I'm in the middle of building a new house with a dedicated home theater. I'll be putting in dedicated 20 amp circuits for the electronics (amp is an Earthquake Cinenova Grande 7). Anyone have some suggestions for making a good electrical circuit - including brands for electrical wire, circuit breaker and outlet?

Budget is $500 for the electrical circuit.
Unless you're wanting to drop a ton more money, I wouldn't worry about the specifics for the materials. There are, however, several things you can do . . .

I'm assuming that this is typical residential construction, wood studs wired with Romex, rather than wires pulled in conduit. First, establish a rapport with your electrican - both the guy actually doing the work, and his supervisor. It doesn't hurt to keep your GC in the loop as well, as some of them are sensitive to people "going around" their authority on the jobsite. If you devote some of your budget to beer for the workers, it's usually money well spent.

Here's a quick list of tiny things that make a big difference:

1. Have everything wired with 12ga Romex instead of 14ga. It's easy to tell - 12ga is always yellow these days. Going bigger than 12ga will usually get moans and groans from the electicians, as it starts getting heavy, harder to pull, and harder to fit through various boxes and fittings - and harder to twist together, fit on the devices' screw terminals, and stuff in the boxes. And 12ga is plenty big.

2. If there are multiple circuits for the audio/video system, have all of them put on the same electrical phase - that is, on the same conductor of the SEC cable coming from the meter. This will greatly reduce the amount of ground-leakage (hum) current flowing between your components.

3. Keep all lighting loads off of the system circuits. If you have a lot of dimmed lighting loads, a lighting control system (i.e. Lutron Homeworks, etc.) or any special lighting loads (neon, cold cathode, dimmable flourescent, etc.), put them on the OPPOSITE phase from the system circuits. This will minimize the transmission of noise from lighting systems onto your audio system circuits.

4. Use good commercial-grade outlets. No need to get tweaky about it, but you might want to go and buy them yourself. Go to an electrical supply house, tell the guy at the counter that you want some of the good ones, and he/she will probably instantly know exactly what you mean. Hubbell, Pass & Seymour, Lutron, and even Leviton make some nice ones, but P&S and Leviton also make cheap ones too, so don't just go by brand. They will most likely have a clamp mechanism where the side screws actually tighten down the wire against the contact, rather than a stupid pressure-fit "cinch" connection.

5. If by chance the outlets do have pressure-fit cinch connections, make sure that the electrician doesn't use them -- rather, the wires should be wrapped around the screw terminals and tightened.

6. Have your electrician twist together all of the wires before putting on the wire nuts. Really. Most don't. You might even spot-check their work at night when they're gone.

7. If the wiring is done with armored (MC) cable and metal boxes, or metal boxes on metal studs, then using isolated-ground receptacles is a good idea. Otherwise, don't worry about it.

8. If there is conduit and pulled wire, then insist that there are separate neutral runs for each circuit . . . some electrical codes will let them share. With metal conduit and boxes, use isolated-ground receptacles.

9. Buy a cheap outlet tester, and check all of the outlets yourself after they're installed.

Following the above might easily blow your budget, and it will take a bit of time and add a bit more stress to your life. But it will make a big difference.
In addition to Kirkus' excellent and very thorough recommendations, you might consider separate external grounding posts for your dedicated lines. Also, I'd recommend a minimum of four dedicated lines (four twin outlets located near each other). Better to have too many than too few. For audiophile quality, relatively low-cost outlets, get Porter Ports (sold on A-Gon by Albert Porter), Acme Cryo or FIM (a bit more $, but very good sounding). Have your electrician install them--safer and much easier than DIY.

With all due respect, 12 gauge wire is the required minimum size for the 20 amp circuit(s) Shak wants. National Electrical Code minimums: 14 ga for 15 amps, 12 gauge for 20 amps, 10 ga for 30 amps.

Putting the audio system on one phase is only a good idea if the electrical system remains balanced.

Outlet tester, check. Wire nuts, check. I tested the outlets in my Mom's house and found a group that showed reversed hot & neutral. After looking at (and moving) all the wiring in the affected outlet boxes, symptoms switched to open ground. Turned out to be a lousy connection between ground wires at a green grounding wire nut in yet another box. On the typical neon-bulb tester, a poor (but not open) ground can cause a reverse-polarity indication


I don't know if it'll fit your budget (but it may, since the walls are open in a house being built), but I'd go with STEEL-armored BX (or conduit, but don't let the electrician talk you into using aluminum--it won't block magnetic fields).

BTW, be aware that there are a lot of nutty, unsafe ideas floating around among audiophiles. Never blindly accept electrical advice from people who don't state their qualifications to offer it. Mine are that I've worked as an electronic technician (and have been involved in repairing industrial wiring on machines) for almost thirty-five years and was a Building Equipment Maintenance supervisor (which included supervising electricians) for 13 months.

Ask your electrician to confirm that any electrical info you receive from strangers is not a violation of the NEC (not that he's going to violate the rules and risk losing his license anyway. And don't bother asking him which brand wire or outlet sounds better, unless you have an electrician who's also an audiophile).
Definetly do the dedicated circuits keeping your digital components on seperate circuits from your analog components .
Also put these on an isolated ground . Are you energy contious ? How many incandesent light bulbs have you switched to flourescent ? It is getting more difficult to isolate the noise makers now a days !
Make sure that your electrician is well versed in isolated grounds . This type of circuit is generally used in the commercial end of the buisness , hospitals and computer centers . I found that residential electricians were aware of isolated grounds but did not know the proper procedure for installing them !

Good luck .
Alrau, I forgot about Shak's 20A specification as I got to typing my diatribe. Of course, at 20A they will be using 12 . . . my recommendation is to use it for 15A circuits as well in new construction. In fact, the electrical contractor that I use doesn't use 14ga at all on new residences.

Also, given the number of receptacle branch circuits on a typical residential panel, it's extremely unlikely that there'd be so many dedicated audio/video circuits as to make balancing the panel difficult while keeping them on the same phase. The only thing is that the electrician gives it a bit more thought, rather than assigning breakers purely in the manner that's fastest to wire.

We're definately in agreement where credentials are concerned . . . but no matter what credentials anybody here has, to Shak we're just some blokes killing time by typing away on Audiogon. Hence the advice on establishing a good, close relationship with the on-site electricians.
Having recently installed two separate 20 amp circuits my electrician was also concerned about ground noise. Double check the grounding.

My run from the electrical panel is 75' using 14 ga with Shunyata Research SR-Z1 AC Outlet.

If your 20 amp circuits really are wired with 14 gauge, your electrician screwed up big-time. As I stated above (and the NEC states constantly), 12 gauge is the minimum for 20 amp circuits.
Correct sir. It's 12 ga.