What’s this all about? Don’t all interconnects sound the same? Ha! We wish!

Interconnect cables are like snake oil, according to some magazines we read...or that we used to read when we had time to waste on stuff like that. Snake oil, you’ll recall from carny days, is a cure for an inexistent ailment, buttressed by pseudo-medical arguments aimed at the scientifically unsophisticated.
     Is that fair? All too often the shoe fits. The audio world includes some remarkably talented engineers who have done original research into every aspect of musical reproduction. Yes, including cables. At the same time, shady entrepreneurs have noticed that a lot of expensive cables look the same, especially once they’re ensconced in one of those slick mesh jackets anybody can buy. It’s possible to pay $100,000 for a pair of interconnect cables. The target clientele: people who want to be able to ask, “Wanna know how much I paid for that wire?”
     But let’s be clear on something. It’s obvious that Dr. McGillicuddy’s Fluvial Tonic and Elixir wouldn’t cure anything worse than the cramp caused by an overweight wallet. You shouldn’t conclude that, therefore, penicillin is also a scam.
     So is there a penicillin of the interconnect world? Yes, there surely is. We own some ourselves. The best have, we are sorry to say, four-digit price tags. We wish we could have spent just $10 instead, but then our entire reference system would be unsuitable for its intended purpose.
     Why should interconnects sound different? A bit of resistance is hardly important here, so why shouldn’t the “sound” of an interconnect, if it exists at all, depend entirely on factors that are easy to manipulate: capacitance, inductance, and the quality of the shielding? Good question.
     A competent amplifier engineer will go to great pains to keep the signal path as short as possible. Carefully tweaking the design, he may discover that shortening the conductive path on a circuit board by a couple of centimeters will make the amplifier sound noticeable better. It’s easy to see why pumping the signal down a conductor that is a meter long or longer is potential trouble.
     We will discuss some of the competing theories in the reviews that follow...and in more cable reviews to come in the next issue, but we can already say certain things to the cable skeptics.
     Most important is this: it’s simplistic to suppose that a cable is a linear device. Like an amplifier, a cable has a transfer function, showing the relation between what goes in and what comes out. That transfer function is not a straight line, it is a curve. Most cables even have a little hysteresis: they will transmit slightly more energy when voltage is dropping than when it is rising. Worse yet, a connection -- whether the one between plug and jack, or among wire strands, may actually conduct slightly better in one direction that in the other (crystal radios function on this principle, which is why some cables will let you listen to the news). A multi-strand wire can actually function as though it were an array of diodes (not very good diodes, of course, but that only makes things worse).
     It’s not easy separating the snake oil from the pharmaceutical research, but there really isn’t much choice.

Harmonic Technology Pro-Silway II
     This is the cable shown here. Its US maker is a relative newcomer to the world of audio cables. There are hundreds of small cable companies of this size, as a tour of a major electronics show will confirm. Some are shooting stars, vanishing as quickly as they appeared. Others find a niche market and get discovered by a significant number of audiophiles. Often they come with a theory, expressed in a white paper. That is the case of Harmonic Technology.
     To make sense of the white paper, you need to know something of the controversy over the crystal structure of copper. Crystals are all around us. Cool a fluid until it solidifies and it may take on a crystalline form. That’s the case of water, which forms the beautiful crystals of frost on the window and snowflakes in the air. Pressure can also cause crystallization, which is why carbon can appear as diamond and not just coal.
     That much is not controversial, but there’s a question that is: can crystals affect the sound of a wire?
     Anyone who tests cables at full level -- as we at UHF used to do until we found that the results were meaningless -- will say no. Electrons can’t “tell” what the structure of the conductor is like. But some designers point to behavior that is quite different at very low levels, when only a few electrons are flowing. Then, they claim, barriers from crystal to crystal have significant effects.
     One of the companies willing to talk about crystals is van den Hul, whose Integration interconnect was reviewed in UHF No. 62 (its speaker cable is reviewed in this issue). The company uses a special process to form a conductor that is amorphous, without crystals. Harmonic Technology has another approach, known as continuing casting. A conductor is formed from a single very long crystal.
     The Pro-Silway is a hybrid cable, using both copper (for lower frequencies) and very pure silver (for the rest). How do the various frequencies “know” which strands they should take? The white paper says that the skin effect, which affects the way higher frequencies travel through wire, takes care of this.
     At a time when some designers leave their interconnects unshielded (perhaps unwisely), the Pro-Silway has a double shield, one of them an aluminized Mylar shield, the other a silver-plated copper braid.
     The RCA connector used on this cable are interesting, because they have a locking collar that works like the one on WBT plugs. Unlike some knockoffs of the WBT, this one has a different appearance.
     How does the cable sound? We connected a pair between our CD player and...

Eichmann eXpress
     The designer of these cables is an Australian inventor named Keith Eichmann, who claims to have made major discoveries concerning cable design and also connectors. The cables themselves are quite inexpensive, as we shall see.
     What is he up to? He has come up with a theory that one of the conductors in a cable must be one third bigger than the other. He calls this the Eichmann ratio. Why? We quote from the company’s publicity:
     The Eichmann Ratio diminishes the effect of both distortions (reactance and skin effect) by forcing the return conductor to respond more rapidly to signals being transmitted through the signal conductor. This provides a balance of reactance and a control of skin effect to the extent that all frequencies appear to have a uniform speed and arrival time.
     What does this mean? We’re not sure. If the signal is speeded up by passage through the smaller “return” conductor, wouldn’t it be speeded up even more if both conductors were small? Is there such a thing as a “return conductor” in an alternating current circuit And is it even true that higher speed makes the signal less vulnerable to cable-induced distortion? (The company uses a bullet analogy: if a bullet travels faster it is less easily deflected by wind.)
     The rationale of the Bullet plug (shown here) is more appealing: it has little metal in it. There is no coaxial metal shell to go about the jack. The shell is plastic, with a single copper wire that snaps onto the outside of the jack.
     We began the session with the Bruckner Scherzo. Because of the price we were prepared for the worst, but...

Complete articles from this issue:
Soundproofing, Big Screen TV's to Stay Away From, Passion A11, State of the Art

Excerpted articles from this issue:
Comparing the Incomparable: Listening in the Store, Antique Sound Lab Leyla, Vecteur Espace, Two Interconnects, Five Speaker Cables, Four Power Cords