Fine Tunes #11
By Jonathan Scull   •   May, 1999 Sometimes you have to sweat the details, sometimes they just fall in your lap. Take Victor Tiscareno. Victor's company, AudioPrism, has been making electronics, accessories, and power-conditioning products for quite some time. While he was visiting and installing a pair of his Mana Reference tube amplifiers for an upcoming review, Victor and I got to talking about power---the kind that comes out of the wall. Victor studied electrical engineering and is very au courant in such matters. During these ruminations he shared with me a recipe for what he calls The Poor Man's Dedicated Line.

When considering typical house wiring, several assumptions can generally be made. Electrical outlets typically follow the shortest path to the breaker box, and they're most likely daisy-chained together. Depending on the amperage of the circuit, this juice-bearing conga line might comprise 12- or 14-gauge Romex wire. Each time the circuit "breaks" for an outlet box, it picks up additional noise from the contact resistance of the hardware (straps, screws, fittings), plus voltage modulation from other household electronics plugged into the line. The farther down the circuit from the breaker box, the more junk is likely to be riding the wires.

The Poor Man's Dedicated Line begins with finding the outlet closest to the breaker box, and powering your audio system from that. The closer to the box you are, the less voltage sag and the happier your equipment---even if the circuit is loaded down with household appliances farther down the line. Install a high-grade outlet at that point and you're in business.

Here's how to do it. Grab a pro-style hair dryer and plug it into one of the outputs of a duplex receptacle of what you suspect to be a daisy-chained circuit. (If you're not sure where the circuit runs, mail-order home-improvement catalogs feature a plug-in module with a device that squeals when it's near the breaker carrying the module.) Insert a voltmeter's positive and negative probes into the second socket. Let the hair dryer rip at full blast and observe that the voltage reading on the voltmeter drops. Move along to other outlets closer to the breaker box until the line sag is minimal. While it's often clear which outlets sit nearest the breaker box, take nothing for granted.

As for the wall hardware, try using Hubbell or Bryant duplex outlets, for their superior mechanical blade retention and screw-down terminals for the in-wall wiring. If you can't find 'em at your local hardware emporium, try an audiophile mail-order house. (A Hubbell duplex from The Cable Company runs $14.95.) And, as always, no matter where you get the outlets, if you're not sure about what you're doing call an electrician! Remember, it's not nice to fool Mother Nature.

You can then channel the juice to your system via any number of audio-grade power extenders, star-wired being the best. Each socket in a star-wired extender has its own run of wires back to the power cord of the extender, rather than being simply paralleled back. If you're on the cheap, use the RadioShack power extenders I mentioned in March. Just make sure they include no filtering or surge protection. If you're able to keep the line free of other devices, so much the better. If not (hey, some of you have a life), grabbing the line closest to the breaker box will still yield a significant improvement.

Tip 2 is an innovative (and free) tweak that mostly applies to those running monoblock amplifiers. However, the theory behind it is important in the overall context of powering your system, and can be applied to stereo amps and, indeed, the entire front-end. As revealed in February's "Fine Tunes," the typical audiophile home has two phases of positive supply: one 110V line from each side of the center-tapped utility transformer supplying your domicile. I also explained how to check for both legs of positive phase, and advised you to run all audio components on the same leg of positive---unless you have monoblocks.