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Reviewer: Srajan Ebaen
Source: Zanden Audio Model 2000P/5000S
Preamp/Integrated: ModWright SWL 9.0SE; Music First Audio Passive Magnetic; Hyperion Sound BEC-P25T
Amp: 2 x Audiosector Patek SE; Yamamoto A-08S; Canary Audio CA-308; Genesis M60 [for review]
Speakers: Zu Cable Definition Mk 1.5
Cables: Zanden Audio proprietary I²S cable, Stealth Audio Indra (x2), Zu Cable Ibis, Zu Cable Birth on Definitions; Crystal Cable Reference power cords; ZCable Hurricane power cords on both conditioners
Stands: 1 x Grand Prix Audio Monaco four-tier
Powerline conditioning: 2 x Walker Audio Velocitor S
Sundry accessories: GPA Formula Carbon/Kevlar shelf for transport; GPA Apex footers underneath stand, DAC and amp; Walker Audio SST on all connections; Walker Audio Vivid CD cleaner; Furutech RD-2 CD demagnetizer; WorldPower cryo'd Hubbell wall sockets
Room size: 30' w x 18' d x 10' h [sloping ceiling] in long-wall setup in one half, with open adjoining living room for a total of ca.1000 squ.ft floor plan
Review Component Retail: Interconnect €795/1m/RCA, €980/1m/XLR; speaker cable €1,290/6.5'/spades/pr

As an old marketing hound, I appreciate the need for spin and story to distinguish one product from another. Build a strong myth and interest will flare. Precious metals audio cables. If copper is good, silver must be better. That means gold must be better yet, platinum even better. Hey, it's only logical. Any jeweler will confirm it quickly with his pricing for otherwise equivalent bracelets. In fact, this very reasoning could seem precisely why Danish Audio ConnecT -- aka DacT of stepped attenuator fame -- has recently formed a new company called DualConnect: to market this rationale in the form of new cables. And as Dynaudio would remind us, Danes don't lie.

From the company's website, we learn the following: "Go for precious metals - silver is good, gold is better! Copper is a good electrical conductor but silver is better. However, conductivity is not the only parameter that counts when choosing conductor materials for high quality audio cables and wires. Conductor materials for Dual Connect cables are chosen in support of our theory that it is very important that electrons be easily moved away from the atom. This results in an easier flow of electrons through the cable, an easier flow of the music signal. The result is a more dynamic, cleaner and more detailed sound without cable conductor distortion. In order to develop our theory, we studied the atom construction of those conductor materials that might be applicable for audio cables.

The condition for a material to even be considered was that it had to have exactly one electron in the atom's outer electron orbit. If only one electron is present there, this electron will be easier displaced from the atom, making it easier for electrical current to flow through the material. Secondly, we were looking for materials where the outer single electron is as far removed from the atomic nucleus as possible. The farther away from the nucleus, the easier the electron is to move away from the atom. We ended up with three main contestants: Copper, silver and gold. Gold is the best of these materials (see atomic graphs above) because it has one electron in the outer orbit that is one position father removed from the nucleus than is the case for silver. Silver is superior to copper in the same way." End of quote.

Seeing that gold's resistivity is higher than either silver or copper (hence its so-called conductivity significantly lower), the assumption that "better/easier electron flow" in the above copy would logically equate to higher conductivity is - um, illogical. Sorry, folks. The following are some values for your reference. Let's start with metal conductivity based on resistivity (but with conductivity values given, ergo the higher the better): Pure silver 105.00 to 108.40 based on purity; pure copper 100.00 to 103.6 based on purity; annealed copper (electrolytic tough pitch) 101.00; annealed copper (deoxidized) 85.00; pure gold 70.00 to 73.40 based on purity; pure aluminum 54.94 (best-case scenario, can be as low as 21.00 for aluminum alloy 220). If we view the same scenario from the resistivity in nano-ohm/meter perspective, the lowest value will be best: Silver 14.71; copper 15.80; gold 20.11; aluminum 25.00.

While the marketing hound in me wags its tail and woofs with delight over DualConnect's atomic coverage, common sense scratches its head for flees. If electron flow were best when the lone electron is farthest removed from the nucleus, shouldn't gold exhibit measurably superior conductivity to silver? In actuality, it's worse than copper and just slightly better than aluminum (from which so-called Romex power distribution wiring is made).

That's why the Danes call theirs a theory. Listening tells them that gold for low-level signal is best. Why? The atomic structure of gold is what they believe outweighs resistivity. Siltech uses a silver/gold alloy as does Crystal. Stealth Audio Cables combines silver and gold conductors in a specific ratio. Analysis Plus offers 'heirloom' gold-over-copper cables for the professional market, their rationale simply indefinite invariant performance due to zero oxidation.

I will also tell you that a very credible electronics manufacturer has offered to send me a you-gotta-hear-this speaker cable. He rigged it up from some 'found' copper with a very fine layer of gold plating. No formal review expected, just Srajan in shock.

So there's evidence that despite its unimpressive conductivity rating, gold has been successfully used for audio conductor applications for a while. I was curious whether higher resistivity would translate to measurable HF attenuation. Allan Isaksen of DualConnect had this to say: "Yes, gold has a higher resistivity but the resulting cable resistance is still low compared to the usual impedance levels at line signal. A 1-meter DualConnect signal cable has a resistance of 1.5 ohms. Generally, pure resistance will not create any ultra-sonic rolloff. Only when it is present in connection with capacitance or inductance will rolloff occur. The ultra-sonic rolloff caused by cables usually has to do with cable capacitances. That's why we have spent significant efforts to minimize capacitances. The result is wider bandwidth."

Technicalia for these Danish cables include a tri-braid geometry, Teflon dielectric and low-mass Eichmann/NextGen-inspired connectors for the interconnect; and integral twin-axial gold-plated solid-core silver conductors for the speaker cable which is then terminated in spades. DualConnect's expressed design philosophy calls for minimizing dielectrics; minimizing inter-conductor capacitance; avoiding conductor twists altogether to minimize energy losses; eliminating surface corrosion (oxidation); and maintaining symmetry between hot and return conductors. It's the less-is-more approach and has stood music lovers in good stead already with zero-feedback single-ended amplifiers and single-driver crossover-less speakers (or those with minimum networks that concern themselves over the time/phase dimension). The tri-braid geometry of the interconnect enjoys precedents with Kimber's PBJ, Sezai Saktanber's SilverFi from Turkey and the Q Tao by Steve Eddy. Solid-core conductors for speaker cables were made famous by TARA Labs' Matthew Bond who built an entire cable empire around RSC -- rectangular solid core -- before confusing the Feds about country-of-origin documentation for his entry-level cables which shook up the usually boring audio news a while back.

The DualConnect company name is very descriptive. Each insulated conductor leg consists of two parallel conductors. Those aren't separated but in physical contact along their sides. Explained Allan: "It's often been discussed whether conductor-casting directionality has any influence on the sound. This led to discussions about directional cables. By using two conductors in parallel, we get the option of matching them such that the conductor-drawing direction of one opposes that of the other. This avoids directionality issues. It doesn't matter now how you hook the cable up. Also, the non-circular cross section makes it much easier to keep large sections of the dielectric away from the conductor."

The literature explains that due to the current requirement of conductor mass in speaker cables, solid gold would become an excessively costly proposition. Hence DualConnect uses silver with a 0.5μm gold plating just to prevent oxidation. Regarding their theory, Allan offered that "I believe that our explanation is the real reason. You are right that copper is a better conductor than gold. But it's also a fact that gold has one free electron two orbits farther out than copper so there is no direct relation between this and the pure resistive conductivity." If the tri-braided 35-gauge pure-gold DualConnect interconnect kicks royal Hamlet arse in Taos, would it be because of atomic superiority? I'd consider such a statement merry myth making on my part. I'd have no way of knowing. Seeing that our hobby is already unduly burdened by too much mythinformation, I'd rather stay clear of attempting any unambiguous cause/effect relationships. The best designers admit -- off the record -- that their art is essentially empirical rather than based on any true knowledge.

In the end, every company needs a slogan. Precious metals audio cables. It does have a mighty fine ring to it - pun intended. So let's leave the heavy explanations to the metallurgists, chemists and nano scientists and focus on what matters in the end: the sound. Incidentally -- and in the spirit of DacT who have long since actively supported DIY -- DualConnect also offers their ready-to-go 0.5/1m and 6.5/13' low- and high-level cables unterminated to DIYers. In fact, their entire pricing structure is based on a consumer-direct model...