Listening #4 Page 3

I called Joe at JPS Labs, to get a few technical explanations. He told me a little more about The Digital AC and how it works.

First, at the heart of this cord are three "very-high-purity" stranded copper conductors, insulated to a 300V rating for approval by UL and CSA. That insulation is also said to contain a special compound that absorbs and, to some extent, dissipates high-frequency energy. But its the energy absorption that is key: The idea is for The Digital AC to act like a sponge for electrical noise, instead of either reflecting noise the way ferrite rings do or allowing it to bang around all over the place the way nothing does.

Then come those filters at the AC and IEC ends. Joe says these are specially tuned for the capacitance and inductance of The Digital AC's unvarying 2m length, in order for them to act as part of a complete and holistic filtration system. These pi networks are "mutual inductance to eliminate common-mode noise, as well as high-frequency capacitors to shunt higher frequencies and 'smooth' the AC as it enters the cord from the wall." The conductors are then encased in a nonreactive aluminum-Teflon shield.

The plug/socket contacts are plated with "high-purity" tin for maximum conductivity, and the cord and its networks are safely rated to operate anywhere in the world. (The Digital AC can be ordered with weird plugs to suit virtually any foreign country you can name, from sunny Mexico to darkest Crackistan.) Joe says that The Digital AC has been on the market since 1997, but given our continued reliance on more and more complex digital devices in our hi-fi systems, he says it's "even more effective today!"

The price is $349—only slightly more than I was going to charge for Art's Black Beauty.

Summing up
In the mid-1970s I worked part-time at a little hi-fi shop in upstate New York. The owner was a conservative, no-nonsense, specs über alles kind of guy (this in spite of some striking weirdnesses in other areas of his life). The in-house repair technician, a good friend who now designs and builds medical imaging equipment for a living, was also an audio skeptic, albeit an infinitely smarter and more open-minded one than his boss. (A side note: We farmed all our tape-deck repairs out to a fellow named Ted Saito, who went on to dual fame as a designer of CD players at McIntosh Labs and an occasional character in Sam Tellig's column.)

This little side trip down Memory Lane has a destination, and it is this: Even back then, and even at a shop that was more Sweeney than Nightingale, we knew from experience that the position and length of an AC cord could affect the sound. Again, that mostly had to do with keeping a power cord from behaving like an RF antenna. While that may seem a less than exotic concern, one must admit that it, too, flies in the face of the attitude that questions whether changing a single 3' length of wire can make a difference in a system where many more feet of conductors remain the same.

What's going on here? My guess is that The Digital AC works not by protecting my delicate hothouse flower of a CD player from contaminants forced upon it by an uncaring power utility, but by preventing my stupid CD player from pissing into its own bathwater, if you'll pardon the expression. Digital audio components can add as much noise to a domestic power spur as certain household appliances; blocking that noise allows a hi-fi system—including, of course, the digital audio components themselves—to perform at its best.

Whether or not that's how it works, I'm satisfied that it does work. And at $349—which is equal to or less than the amount some enthusiasts, myself included, will spend on a special isolation rack or stand for their CD players—I believe that The Digital AC is fairly priced, both in terms of the sonic and musical improvements it wreaks and its apparent manufacturing cost. Considered in the context of other accessory cables I've seen, The Digital AC is actually something of a bargain.

By the time you read this, I'll have mailed JPS Labs a check for this one, for use with my Sony SACD player. Since its effectiveness was not quite so pronounced with the Linn Lingo, and since I don't actually own a Linn Lingo, I'm holding off for now on buying a second Digital AC.

But The Digital AC's greatest value may be as a lesson to a know-it-all reviewer: My job is to try everything that comes my way with an open mind—even things that strike me as unreasonable or unworkable. This doesn't mean I can't have a point of view. I'm still free to make fun of things I think are stupid, as long as I'm also willing to make fun of myself when I'm wrong.

Most of all, it means I mustn't get lazy. I'm sure that somewhere in the Betty Crocker organization is a tester who thinks au gratin potatoes aren't worth the bother, yet she must keep searching for that one recipe that will knock her senseless. So it goes.

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