Silver Plated, Copper Conductors

Q.) First off, I like your cables very much, and use them in my system. After reading about various manufacturers using silver-plated copper in their interconnect and speaker cable designs, I was just curious what it is about copper that you like so much that you prefer using it over silverplate.

A.) Well basically it sounds better. Cables are a dynamic system, prone to ring. Like any other system without a little loss they will resonate, like a speaker box with no stuffing inside or phono cartridge with no damper. Ultra pure copper is ideal for audio purposes in most designs.

Plated conductors are inherently impure mediums with bi-metal junctions and are not suitable for audio use in my estimation. - George

Q.) Why not use copper RCA plugs, as opposed to low conductivity brass with silver plating and rhodium flash?

A.) The reason for brass is simple, you must keep the connector as much like the conductor that feeds it as possible. In the case of our RCA connectors, low current high impedance transfers are best served by small conductors. Large cross-section conductors ring and are of no positive value. Our RCA's conductor is essentially a thin silver tube (the plating) protected with a Rhodium surface, the low conductivity brass is simply good structure. In the case of speaker spades we use thick, ultra pure copper with a silver/rhodium plate to suit the high current, low impedance application. - George

Q.) A customer asked what eutectic brass is? Doesn't eutectic have to deal with the melting point of the metal and that this is a low melting point material? He also stated "From everything I have read they tend to identify brass as a fairly poor conductor indicating that only 28-30% of the signal is being transferred." While I would tend to agree with this statement, I can not dispute that your connectors sound the best out of all I have used with Solid Core Silver. The best connector is no connector, but since hard wiring is usually out of the Question, if I had to choose, I would say I like yours the best. Why did Cardas decide on Brass over Copper for the connectors? I know it is easier to machine. Brass is 70% copper 30% Zinc, correct? - Drew

A.) The decision to go with this brass alloy was made because it sounded best of all the materials we tried. The basic reason is it eliminates all the thick conductors in the connector. Thick conductors in connectors, like in cable, cause a ring. The conductive path in the connector becomes the silver plating which is similar in character to the conductors in a good cable. The brass material was selected because it is a low permeability, high resistance conductor  and because it machines well. We tried many metals in the beginning. Most did not compare well to this alloy. Other alloys that fared well were beryllium bronze and beryllium copper. Pure copper and aluminum did not work well to my ears. - George

Q.) What guages of chassis wire do you carry? What is the composition made up from?

A.) We have "Golden Ratio constant 'Q' litz " conductors from 33 awg to 9 awg available. If you have special needs outside this range we can make any size. All our Chassis wire is made from ultra pure ultra soft copper. We also make our own stranding for the litz and supply stranding to other manufactures. One reason we do not advertise is the fact that most of the manufactures in the industry already use our products and know what we sell. We have ultra pure copper (either 99.999+ or 99.9999+, it is some times hard to tell because we cannot find any impurities at all on the surface). The copper strand is available in many coatings or bare with a proprietary vapor protection. Strand sizes currently being produced run from 48 awg to 19 awg. Minimum purchases do apply. We have ultra pure (either 99.999+ or 99.9999+) silver strand available in many coatings or bare with a proprietary vapor protection. Strand sizes currently being produced run from 38 awg to 16 awg. Minimum purchases do apply. All metals used in any of the above are sold in absolute annealed state unless otherwise requested. - George

Q.) I read ads by other cable manufacturers who claim to use special types of wire such as Cardas Fine Wire. Could you please explain more about this product.

A.) Like many products Cardas Fine wire developed out of a need that could not be filled. The availability of ultra pure, ultra soft conductor strand had decrease to the point of unavailability in this country in the mid eighties, due part to the development of and evolution of mass production techniques such as resistance annealing and mandatory recycling. Usable copper was cheap and plentiful, however, super pure and ultra soft copper became the mythical unicorn. The general condition of available copper became so bad that manufactures began going off shore for product. Still the consistency of product was poor and costs soon became astronomical and we were forced to make our own.

We found that care and consistency at every step of the drawing process and a bunch of nines after decimal point were not enough. It made little sense to start with pure copper just to have it harden and oxidize during the drawing process and after manufacture. Instead we developed a process where the copper is actually purified and super annealed during the drawing process and developed a coating process to protect the copper between steps and after production.

At first the only customer we had was ourselves and our livelihood depended on the perfection and purity of our metals. We are still our own best customer and we still make the most perfect product we know and absolutely do things the best way possible. We start with the best available copper on the market, ultra pure bar with 0 recycling content. We then, with a complex and highly proprietary process, reduce, refine, draw, polish, and anneal the conductor keeping a coating on the conductor at all times during manufacture. Even "bare" copper retains a proprietary vapor coating for several months, the distinct straw color of our copper is due to the absolutely oxide free mirror surface. The purity is beyond our ability to measure and we typically find surface conductivity in the 103 range in the ultra fine series coppers.

Unlike conventional coppers that are quick annealed with an electric current process called resistance annealing our coppers are annealed the hard way, in hydrogen reduction ovens. Not just at the end of the drawing process, but at every step in the process in the ultra grades and every other step in the super.

Custom diamond dies polish the wire as it is drawn, not just at the final step, but at every step in the process. The conductor is always coated to protect it at all times even between drawing steps. At Cardas we use urethane enameled conductor for the construction of our cables. This is a very permanent protective process.

Beginning in 1998 we also make un-enameled conductor strand available to other manufactures. Today most almost all the ultra pure copper used the high-end audio industry comes from our plant. In addition to the super fine and ultra fine copper, we also manufacture super and ultra fine silver using the same care and processing. We are currently supplying stranding from 19 awg to 50 awg in copper silver and beryllium and 45 awg to 49 awg in Gold. - George

Q.) I'd like to know what makes Cardas solder better than all other solders for audio work. What advantage does Cardas solder have over other eutectic solders that makes it worth its much higher price? On the one hand, there is Jennifer of Jena Labs claiming that no other solder should ever be used, and on the other hand there are people in DIY chat rooms that say these exotic audiophile solders are a waste of money and no better than products like Kester. Thanks for your response. - Michael

A.) Hi Michael. The vast majority of solders in the world are slurries or mixtures such as 60/40 tin lead solder. They go through a slurry stage as they solidify wherein one component solidifies first and then another. The result is a solder connection rather than a joint. Eutectic solders such as Kesters Ultra pure Tin/lead Silver are in fact excellent because they solidify at a temperature lower than any of the component parts thus they form a solder joint rather than a connection - the key here is the eutectic formula which must be very precise - the solders are obviously different in that they set up with a mirror finish rather than a dull finish, the reason they do this is because they solidify as a unit. The week link in the solders is contamination - the molten solder easily dissolves other metals, this is no problem if you are soldering to a metal that is part of the eutectic mixture (such as tin or lead) you will get contiguous flow right in to the joint (easy to see) but if you solder to a dissimilar metal (such as copper or silver) you will see an obvious dulling at the connection where the eutectic formula fails and and the continuous joint becomes a connection. Cardas Quad Eutectic is tin, lead silver, copper, eutectic. The results are obvious. Most highend products use this solder and other cable manufactures have been using it for over a decade - to them it represents good sound and absolute reliability. - George

Q.) What is Quadeutectic solder? What percentage of each element does it contain; tin, silver, lead, copper?

A.) It is tin, lead, silver, copper eutectic. 61/35/3/1 is the approximate ratio. The key is a ratio that has several decimal points after each number. It is very precise in order to hit the "eutectic point". It took years to pinpoint. - George

Q.) I have just ordered a bunch of Cardas AGMO Male RCA's and was wondering if you have any technical documentation that has electrical conductivity, resistance, and impedance for all of your Male RCA's, Female RCA's, Binding Posts, and Speaker Cable Termination Spades. I understand that the Rhodium and Silver admixture is marketed by Cardas as a more rugged coating than gold, and was wondering what the end product electrical conductivity is of the combined plating material. Are all your termination products pre-coated with nickel prior to coating with the final gold or Rhodium/Silver plating as some websites have tried to lead me to believe? I am in the process of building many pairs of speakers, interconnects, speaker cables, and amplifiers and would appreciate it greatly if you could give me any of the above information that you can. - Graham

A.) The RCA's are 75 ohm except for the SRCA's that are 100 ohm. The plating is a rhodium flash over a heavy silver sub plate. The conductor/conductivity/resistance in practical application would be the same as very high purity silver. In the case of RCA connectors where the primary conductor is the plating substrate and the same as copper in the case of the binding posts where the primary conductor is the copper of the post itself. There is no Nickel used in the rhodium plating process. Nickel is not used except in decorative gold plating or where specifically stated, such as in the RCA caps. Gold plating is inferior to the silver/rhodium process in every way. Decorative Gold plating that is used on some connectors, like Radio Shack, is a very poor choice for connectors because of the nickel sub plate. The only proper gold plated connectors I have seen are from Audioquest. The sonic difference between a plating that contains nickel and a silver/rhodium plate can be enormous (as in the 1/4" head phone plugs).

Sonically and electrically the best speaker connector is the CPBP with silver contact posts. The pure silver/rhodium plated posts are a close second. The impedance of the speaker connectors is extremely high, but I have never measured them. Characteristic impedance, per se, is not an issue in audio circuits because the wavelengths involved are way to long for a transmission line and audio circuits do not match impedance. - George

Q.) Dear Colleen, My name is Pisut. I live in Thailand and unfortunately I have become unintentionally involved in a controversy within the Thai audio system circle.

  The subject of debate is the Cardas electrical plug. Those in the know are split into 2 groups, one telling consumers that the plug is a Cardas original and the other says it’s from either Eagle or Leviton. Personally I would like to request further information on the matter. Are all the plugs manufactured by Cardas?

A.) No they are not. We do not now, nor have ever manufactured Electrical Wall Plugs or Receptacles. We are currently using Furutech plugs on our Power Cords. We are not currently selling Electrical Receptacles of any type.