Power to the People

It’s a commonly recognized fact that contaminated fuel can inhibit the performance of the best engines. In the same way, noisy electrical power can limit the performance of home-entertainment gear.

Dedicated Lines and Proper Grounding

There are many approaches to cleaning up your electrical supply— some derided by old-school technical types, others almost universally recognized as real problem-solvers. One of the most persistent theories hypes the value of the “dedicated line,” an electrical line that goes from your service panel (or “breaker box”) to your A/V gear, and nowhere else—one that’s not interrupted to energize lamps, household appliances, computers, or any of the other thousand devices in your home that depend on alternating current. The other closely related theory is that proper grounding is essential for maximum performance. In my experience, both have proven true.

In my 25-plus years of working with, playing with, and installing audio and home-theater equipment, the dedicated line is the one solution I never had a chance to try personally until two years ago. As part of an ongoing remodeling project, I decided to move a rack of equipment from the front of my media room, where it had stood next to a tall loudspeaker, to a spot to the side and behind the sofa, out of sight. I love my electronics but hate looking at them, even if they are pretty.

Moving the gear offered the perfect opportunity to install a dedicated power line. My service panel had one blank space, large enough for a two-pole 20- amp breaker. I coerced my custom installer buddy Carlos Shelton to help me with pulling the stiff 10AWG (American Wire Gauge) Romex through the attic, down through a wall, under the floor of my home-theater room, and up into a sidewall near where the new equipment cabinet would reside. At the same time, we pulled speaker cables and subwoofer feeds under the floor, helping to eliminate technophile clutter and vastly improving the look of the room. In Photo 1, the dedicated line is the bright orange wire on the right side of the service panel. Photo 3 shows a properly wired duplex outlet.

I purchased a couple of Hubbell duplex AC outlets from Jim Weil of Sound Applications in Berkeley, California, the same type used in his best power conditioners. He offered a couple of useful suggestions on installing the dedicated line, including running separate lines for digital and analog equipment, and “keeping them at least 18 inches apart throughout most of the run” to minimize induced noise. A double run proved impractical in my situation, but the improvement from a single line was so substantial that I’ve promised myself the next house will have at least one double run, and maybe more. Photo 4 is the dedicated outlet shown in use.

(Warning and disclaimer: Drilling the needed holes, pulling the wire, tacking it in place, wiring the outlets, and connecting the breaker are all straightforward tasks, well within the capabilities of any home handyman. That’s why all the tools and components are available in building supply stores nationwide. Working inside the service panel, however, could expose you to potentially lethal high-current 220-volt AC. Do not attempt this yourself: Hire an electrician.)

In the sheetrock behind the new cabinet, I cut a hole for a two-gang outlet box (Photo 2), within a few inches of a new TV cable. Since one of the most common, most persistent, and most annoying problems with home-theater equipment is hum caused by improper or incomplete grounding, I took the opportunity to ground the cable to the ground screw on the dedicated outlets and also ran a 12 gauge wire from there through the wall to the outside of the house, where I soldered it to a six-foot length of 1" copper pipe driven into the earth as an auxiliary ground.

Weil recommends copper pipe rather than solid copper rod because copper pipe has more surface area. It’s far softer than solid rod, however, and deforms easily when you hammer it. There is nothing about an outside auxiliary ground that violates the electrical code. Buildings in electrically active areas such as Florida often have multiple grounds for better lightning protection. You can also treat the soil around your ground rods with an electrolytic solution to improve conductivity.

The National Electrical Code specifies that every electrical feed to every residence be grounded to an eight-foot copper rod driven into the earth. The NEC also specifies that TV cable must be grounded where the cable enters the building, something typically done by running a length of wire from a cable grounding block to a clamp on a cold water pipe, the theory being that cold water pipes are in contact with the earth and therefore provide a good ground.