A.J. van den Hul: Going Dutch Page 5

There are also a lot of mechanical reasons why products change—the bending of metals, for example. Producing wires for conductors is a very deteriorating process, particularly when you chemically coat copper with silver. In the process, you bend the cable, stretch it, bend it, stretch it again—30 or 40 times—so the wire is worn out even before it's silver-coated. That's one of the reasons why silver-coated copper sounds harsh. There's also the chemical deterioration under the silver which starts to break down the structure of the copper before even the slightest coating of silver is done. The finished wire has already deteriorated. It looks very nice and shiny on the outside, but the enemy is inside. You have fundamentally killed the product. So silver coating, chemically, is the wrong way; silver coating mechanically is a better way. That's what we do with the better type of cables: we have a mechanical instead of a chemical coating.

So, to answer your question: I was unhappy [with these problems in metals]. Perhaps, I thought, there was a different way. I was always telling my students, "Never do it the traditional way. Always do things differently." When everyone else walks from A to B, you walk from B to A. If you look at the same things from a different direction, you come up with different ideas which help you to better solve problems. Never copy solutions from someone else—always come up with better ones. That is my main point.

Change everything. Change the conductor, the insulator, the layout—whatever you can think of. At worst, it will be the same. If your ideas improve the situation, you will have found a better way.

Norton: Did you try any other materials?

van den Hul: I'm always doing experiments in my mind. It saves me time and money, and I can do the experiment in an airplane, when I can't sleep at night, or whenever. It's a very fast way of coming to solutions, just mentally working the problem. That's how I came up with this material. I'd been working with other materials, too, but this is—so far, I think—a very good solution. I know of better solutions than carbon, but they are very hard to do at the moment. There's a technical threshold, therefore I'll do carbon now.

Norton: You use carbon for your interconnects , but on your Revelation loudspeaker cable, you had to go another route—because of the resistance problem?

van den Hul: My target is to produce a speaker cable—the Third—with an impedance of about 0.05 ohms/meter. At the moment we have reduced, by technical improvements, the impedance of the fibers by a factor of six. We want to go down to a factor of ten, then by another factor of ten. So, fundamentally, I'm working on a program to work down the impedance of the fiber by a factor of 100. Then we can produce the Third. It would otherwise be too bulky.

Norton: Do you reduce the resistance by increasing the size of the conductor?

van den Hul: No. That's the technical way. The "physics" way is to line up the carbon in a more correct way, with better conductivity as a result. Carbon is, normally, randomly ordered. Our method is to apply extra energy sources to line up the carbon in a better way. On the carbon itself, and the application of carbon to audio, I have obtained a 1990 US patent.

My aim is ultimately to make a metal-free speaker cable. All metals have chemical and mechanical activity. It's the same as with your first bicycle. It became worn out—parts rusted or broke off from metal fatigue. The same with your first car. That's the natural way of metals. Metals always run down in a most disordered fashion. Man is there to organize, purify, and bring metal up to the highest possible level of purity; and as soon as it's there, it will collapse again. So it's the eternal movement, up and down, fighting the natural tendency of metals. You have to find a different material so that you don't need to fight it anymore.

The second—and most important—goal was to come up with a material that was environmentally friendly. By using so much copper in conductors, we spend the capital of this earth instead of the interest. The capital is the original resource. There's much more carbon on this earth than [there is] any metal. The good thing about carbon is that it can be recycled. The First is a completely recyclable product—we chop it, melt it again, and use it as an extrusion layer over our speaker cable. There's no other cable manufacturer able to recycle his product with his own processing. They only burn it and create a lot of waste—the impurity of the copper which is left is so great you can't use it any more. I also wanted to use, as far as I could, natural materials to be sure that I was attacking our environment no more than was strictly necessary.

Norton: There are, of course, two conducting elements in a cable: the conductor itself, and the connectors. Are there any particular problems you've run into with the connectors using this particular material?

van den Hul: Yes. So far the product can't be soldered. At the moment, we clamp it.

Norton: So there's no solder to make an airtight join. While that wouldn't be a problem with the carbon, which doesn't deteriorate, there would be a problem with the connector itself.

van den Hul: Currently. There's always a metal part involved. The best idea I could come up with was to let the group of fibers continue and use that as the center pin of the connector. That's another thing I've been working on—to make the whole thing of pure carbon. But that's a technology you might expect from NASA. It's a little tough for a small company to realize all those things. But the ideas are there.

The difference between a metal conductor and this carbon conductor is that low-level information passes extremely easily through the carbon, where it would be blocked in a metal conductor. Because of boundaries built up in the metal, the center part of the sinewave, near the zero-crossing point, cannot pass. The result is a kind of crossover distortion, where the low-level signal disappears completely. With the carbon cables, even though it has a higher DC resistance than copper, there is less of a blocking effect. So the sound is much more detailed, without the unnatural aggressiveness caused by the sharp edges of this "crossover distortion" produced in a copper wire. That means that the sound is much smoother and has higher resolution at low levels than in any metal product.

Norton: When you use the carbon interconnect between, say, a CD player and a preamplifier, its relatively high impedance has little consequence; but if you use it for a phono interconnect, wouldn't it add significantly to the source impedance of the cartridge?

van den Hul: It does add to the source impedance of cartridges, but a lot of cartridges play better when they are loaded with high impedance than with a lower impedance. It doesn't have that much effect. The current is practically zero, so the voltage drop by itself is also very limited. The First gives superb results with phono cartridges because all you're dealing with is low-level information, where the performance of conventional cables is worst.

Norton: I've always wondered whether you're better off with long interconnects and short speaker cables—which is the most popular option today—or the reverse. With the fact that your cable is of fairly high resistance, is there any situation where there would be a problem using unusually long interconnects between the pre- and power amps?

van den Hul: There are two questions here. First, in what situation do you use a long interconnect and a short speaker cable, and in what situation do you use the opposite? In my experience, and based on what I have just told you about low-level information, the shorter the cable, the better. With a poor-quality interconnect, keep it as short as possible, and make the speaker cable a little longer. But with high-quality cables, do the opposite. That is, the power amplifier controls the speakers better through a very short speaker cable. The longer interconnects don't create much of a loss, because a power amplifier has an input impedance of around 50k ohms. This cable is about 50 ohms a meter, so 10 meters is 500 ohms; 500 ohms is 1% of 50k ohms; 1% calculated in dB is 0.01dB, or whatever it is, so you don't create any losses.

Norton: Is there the same type of skepticism about cable sound in the mainstream European audio press as there is in this country?

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