Cable Reviews

"They cost WHAT? A hahahahahaaa!"

Nothing is more guaranteed to amuse non-audiophiles than the subject of high-end cable pricing. "I'm sorry. I don't mean to laugh at you, but...bwah ha ha haaa!" Who can blame them? Even in the hi-fi camp, there are those who are convinced that wires are no more than hideously expensive tone controls. "Hmmpf, cackle. Snort!"

Others hold that, differences in resistance, capacitance, and inductance aside (footnote 1), the whole high-end cable market is just an exercise in mass self-delusion. "Really, how much are they?"

Regular folk, like my friend Randy—who has one child in college and two more in high school—just purse their lips and bite their tongues to keep from commenting on the whole subject. "WHAT!?!"

In my experience, however, I've heard audible differences among the available interconnects and loudspeaker cables—no matter how much I might devoutly wish otherwise. Don't look to me to explain why. Far from finding that there's one true path to audio nirvana, I have a boundless gullibility when it comes to cable technology theories. I love 'em all—especially the really goofy ones.

My problem is that it all makes perfect sense while I'm listening to designers expounding upon them; only several hours later do I do a double take: "Hey, wait a minute! How did that traffic cop get into the wire in the first place?" This is because I try to keep an open mind—well, certainly one that's unburdened by any real grasp of theory.

My dalliances with cables of the week lurched to a screaming halt last year, when I received a set of Transparent Audio Reference interconnects and speaker cables. These were products unlike any in my experience. Forget veils lifting, windows opening, or any of the tired old audio clichés: I'm talking about nothing less than communion—an act of sharing thoughts or feelings in spiritual fellowship. If Cecil B. DeMille had directed the encounter, clouds would have parted, a ray of light would have fallen on my speakers, and choirs would have sung hosannas.

Instead, I tore my finger on a splinter while crawling around to connect the speakers, and then sat bleeding onto the couch, enthralled listening to Beethoven piano sonatas. But you get the idea.

Wire we talking about this?
What are cables supposed to do? On the most superficial level—and also at the deepest, most functional level—they're supposed to connect everything together. They transmit the signals from source components to the amplification chain and then on to the speakers. No matter how great the components, if you don't got no cables, you don't got no sound.

Ideally, cables would perform their job without adding anything to the signals they're carrying, and would deliver up all of the signal going in. You're probably already hip to the fact that such a simple-sounding description is an impossibility here in the material world, but why?

First is the physical nature of metallic cable—its molecular structure alone ensures that noise will be added to the signal. Second, no matter how you design the cable, you have to deal with the trinity of resistance, inductance, and capacitance. Resistance, which refers to how hard it is to push current flow through a cable, is the easy one to design around, and is seldom a problem for metallic cable designs. Capacitance and inductance, on the other hand, really throw a kink into designing a cable which resembles our theoretical ideal, because they're storage elements—which means that they have a strong (ahem) resistance to surrendering all of the signal they carry. It's their nature to retain it (footnote 2). Moreover, inductance and capacitance perform a kind of dance in an audio cable: the cable is primarily inductive, but at some frequencies, it becomes capacitive.

The point in frequency where a cable changes from inductive to capacitive is referred to as the resonant point, and that point is approximately 1300Hz, generally speaking. As the frequency approaches 1500Hz and below, the cable starts offering increased resistance to the LF component of the signal. Random noise, not to mention a host of other interactions, dictates that the changeover is not a specific point but rather a broad band, wherein the signal changes from inductive to capacitive and back again. The ear perceives this interaction as cancellation—you end up losing information that cannot be recovered.

Finally, we come back to the most basic of all cable functions: It connects everything together. The problem is, at each stage it connects items of differing impedance. The signals that are rejected because of this mismatch reflect back toward the source, where they mask low-level detail.

Whew! In this very much not ideal world, cable has a Sisyphean task.

Network theorem
Designers get around these problems in many different ways—and some just ignore them. Jack Sumner of Transparent Audio maintains that building a compensatory network into the cable itself is the way to go. In this, Transparent cables are not sui generis; MIT's cables also employ networks, although the two product lines are quite different. "We sold, and built, MIT products for eight years," explained Karen Sumner, "so it would be pretty surprising if we didn't learn a few things, including where our design philosophy diverged from theirs."

The first thing that most folks—even non-audiophiles—notice about the Transparent cables is the network itself: the pods sprouting off the cords give the cables the air of electronic componentry rather than mere wires. The natural question is, "What's in the box?" But other than replying that it consists of a low-pass filter network, Transparent ain't saying. Ask what it does, however, and it's hard to get them to stop talking.

"By increasing the amount of inductance, we change the point where the cable changes to capacitive," Jack Sumner explained in an interview last February. "The first thing that we're concerned with in a network is rolling off the ultrahigh frequencies. A lot of people just don't understand how this can [favorably] affect what you hear. Our model comes from thermodynamics: if you put heat into a system, a certain amount is transformed into a lower form of energy, so it's not usable as heat. The same thing is true in a cable: if you have a lot of very-high-frequency component, like RF, some of that is actually changed into a lower form of energy. And that gets down into the audible bands as noise—which obscures low-level detail, like the first and second reflections off the walls and ceilings of concert halls. It doesn't necessarily make common sense, but we're throwing away information—information that you don't need.

"The second thing a network does is more closely match one impedance to another. You always have a change in impedance going from one component to another. The signals that don't pass through the interface are reflected back into the amplifier as out-of-phase information—which really screws up such things as low-level detail.

"The third and most important function of the network is that it lowers that resonant point where inductance changes to capacitance, by adding inductance to the cable. This is the part that's proprietary—you can't just add inductance. Take a cable without a network: it has a flat frequency response and uniform group delay. Uniform group delay means that the harmonic structure stacks up the same way at the end of the cable as it did in the beginning. When you hear a real cymbal, you hear the stick striking the brass, followed almost immediately by the overtonal structure that finally results in the shimmer. Just adding inductance to the cable would give a more accurate impression of the fundamental frequency—the strike of the stick—but it would destroy the time and frequency relationship of the shimmer. When we add a compensatory network, it becomes possible to lower the resonant point without affecting the group delay or frequency response. We believe lowering the resonant point is the only way to achieve the proper relationship of fundamental to harmonic."

See what I mean?

Music is the art of thinking with sounds
Now, I've already said that I'm a sucker for all cable theories, so I'm probably not the one to look to for verification of Sumner's design brief. But I've spent the last year or so listening to these cables—and to some earlier samples of the Music Wave Reference speaker cable—trying to suss out precisely what's going on. During that time, I've used the Transparent products with every component that's passed through my house, and, except in conjunction with a couple of loudspeakers—the Monitor Audio Studio 2s and the Sonus Faber Minuettos—I think they've stood head and shoulders above any other cables with which I've had experience. (I have not yet listened to the latest designs from either MIT or Kimber, which have impressed me in systems other than my own.)

First of all, you have to notice the silence of Transparent's wires. We commonly think of silence as the lack of noise—not incorrectly, I concede. But in music, silence is not just the absence of something else, it's a value—a thing unto itself; in fact, in most theory classes, the rests are taught before the notes are. The Transparent designs portray silence as a physical, not just theoretical, reality. For the first time, one can hear low-level details that have never been audible above the inherent noise of the wire. My long-time reference CD of Leonhardt's and La Petite Bande's performance of Bach's Mass in b (EMI CDS 7 47595 2) illustrates this surprisingly well. In the "Credo," there's a pair of playful moments which reveal both Bach's wit and his religious passion. The "Credo" is the part of the Mass wherein the core beliefs are articulated, and most composers set it to fairly serious-sounding music.

Not cool papa Bach, though. Over a descending ostinato from the lower strings, he has the various choral sections come in sequentially, round fashion, with the first line, "Credo in unum deum." Set over the walking bass of the cellos and basses, it's a surprisingly lighthearted—some might say rocking—reading of the creed. But Bach doesn't stop with this display of religious joy. Set into the overtones, and quite independent of the fundamentals, is an ecstatic little dance that displays a completely different rhythmic emphasis from the sung—and played—tones. You don't even hear it on most hi-fis—it's one of the obvious ways in which live music is richer and more profound than the canned variety. I have never heard it more explicitly stated on this disc than when using the Transparent cables.

Almost all components have an effect on the tonal balance of recorded music, and cables are no exception; but I never felt that the Transparent Reference products were imposing a particular sonic signature on my system. Changes in individual components produced clearly audible changes in system character—frequently radical ones. If the cable were asserting its own personality, I don't believe this would be the case. The (forgive me) transparent nature of these wires helped me to hear much more clearly the shortcomings of individual pieces of gear—especially those of less-ambitious equipment. This is primarily a comment on the bizarre world of audio reviewing, as no sane person is going to attach a $500 integrated amp to a pair of $4k speaker wires, are they? Well, if you're thinking about it, don't. Both Transparent and MIT make reasonably priced networked cables. While wire is essential—no system will work without it—wires are not the first place to put your silly-money.

I was also consistently impressed with the coherence of the Reference cables. I don't believe I have ever heard my systems sound more seamless from fundamental to highest overtone. This consideration is important, and almost universally overlooked. It also takes us out of the purely tonal and into the temporal realms. It's not uncommon to refer to the overtone structures as stacking above the fundamental. This would almost be an accurate way to illustrate them graphically—if we were to carve them out of a piece of music. But the truth is that overtones are inherent in and inseparable from the fundamental. We describe them as having a separate existence, because our auditory system favors some frequency ranges more than others. And, not so coincidentally, because many components lack uniform group delay—further distorting our perception of the individual note. If you start those individual notes in motion—in time as well as in pitch, creating music—things really start getting confused.

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Footnote 1: I'm always puzzled why those of the logical positivist persuasion, expounding interminably that L, C, and R are the only parameters that matter in cable design, forget that such well-documented factors as dielectric absorption and hysteresis also play a major role. I remember arguing this with a brilliant RF engineer. Ultimately, frustrated by the non-communication, I asked him if he would use cables with a polarized dielectric such as PVC for his RF work. "Of course not," he spluttered. "It would be useless!" "So why do you continue to insist that the dielectric doesn't matter when it comes to audio?" "Because who cares about audio-frequency performance?" was his angry response. "I do!" I said.—John Atkinson

Footnote 2: Inductance and capacitance are both reactive elements, which means that they react to AC signals. They differ, however, in that inductance becomes more reactive at high frequencies, while capacitance is more reactive at low ones. By more reactive, we mean that the effect increases; thus, capacitance resists the transmission of LF, just as inductance resists high-frequency components.