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  Cable Products > xStream Resolution Audio Cables xStream Resolution Audio Cables More Info Starting at just $149.95!  You’ve probably read the claims cable manufacturers often make of “increased soundstage”, “warmer”, “better bass”, etc. In fact, there are perhaps as many claims as there are cables, but all seem to have one common theme: they have “more” of something.The truth, as we see it, is this: cables cannot improve your system, they can only be built to have as little negative impact as possible. Are some better than others? Absolutely! But not because they '”add” a certain quality to the sound and certainly not because they subtract a quality. A properly designed cable should pass the musical information with as little loss as possible, while maintaining an electrically quiet environment. Our good friend and colleague Bill Lowe, of Audioquest cables, has been preaching the same thought process for years and we couldn’t agree more. In building our xStream Audio line of cables we wanted to focus on our own version of the medical Hippocratic oath to “do no harm”....yet when you hook these up, we want your jaw to drop. The determining factors Audio cables, whether interconnect or speaker, rely on two main areas for their ability to pass  electrical signals unimpeded: materials and construction. The purity and conductivity of the conductors, the method of shielding, the quality of the connectors, the dielectric qualities of the insulation and the geometry of the wire-lay inside the cable all play a major role in a cable’s mission statement: do as little damage as possible.To achieve these goals, you need the best conductors, shielding, connectors, insulators and winding techniques. The PS Audio xStream Audio Series of component and loudspeaker interconnects are just about as close to perfect as you are likely to find anywhere and at any price. Overview of the xStream Audio Series Our goal was to build a zero-loss interconnect that would withstand the test of time and win the approval of critical listeners the world over. To respond to the zero-loss challenge, we decided there are only two acceptable materials and one acceptable construction technique. This resulted in two models: Reference and Transcendent. Both Reference and Transcendent use exactly the same connectors, the same shielding, the same dielectric materials, the same outer jacket material and building techniques. In fact, the only difference between the Reference and Transcendent is the conductor materials themselves. Reference uses PCOCC single crystal copper and Transcendent uses pure, solid silver.  To use anything less would be a compromise. Connectors A good connector is essential: if you fail to connect properly, then all the care and expertise applied to the cable conductors and shielding are for naught. The xStream Audio Series interconnects use either our new locking RCA connector or our high end XLR balanced connector. Both are made from high purity copper and then gold plated. The RCA connector is the locking style, so you can easily slide it into the female RCA, twist the barrel and the connector is locked into place. All connections are terminated with high silver content solder, sleeved, and inspected under a microscope for quality. Shielding Proper shielding for audio interconnects is essential if you are to enjoy everything your music or theater system has to offer. To create a properly shielded cable, you need a high frequency, low frequency and dissipative shield system, terminated at one end of the cable only (otherwise the shield acts as an antenna). Both the Reference and Transcendent audio cables are triple shielded and single point terminated to reduce noise to astonishingly low levels. Low frequency shielding is handled by a 144 strand 90% sliver plated OFC copper braid just under the outer jacket of the xStream Audio cable. High frequencies are shielded by a double sided aluminum foil shield next to the conductors and the dissipated energy shield is made from carbon impregnated PVC plastic, sandwiched between the low and high frequency shields. All three of these shields are then connected to the source end of the cable and open at the output end. Arrows on the cable indicate the proper direction. Low absorption dielectric Conductors must be insulated from each other to work. Each insulator contributes to either signal loss or time smearing (signals not arriving at the same time) to some degree, so the trick is to maintain as little loss as possible. To keep the hot and neutral electrical isolated, we turned to the second best dielectric insulator in the cable business, Polyethylene. Polyethylene is an excellent insulator but not as low in dielectric absorption than the best insulator, Teflon.  We would have used Teflon but Teflon is problematic because you must encase the entire conductor in a solid Teflon sheath, increasing the surface area of the Teflon-to-conductor boundary. However, we can solve this dilemma by using both Polyethylene and air as the dielectric. This is known as Polyethylene foam. Polyethylene foam (PE foam) is created by injecting bubbles into the Polyethylene and foaming it, which dramatically reduces the boundary area of conductor and insulator to a minimal level that exceeds the dielectric properties of even Teflon. Both the Reference and Transcendent lines of cables use PE foam for the insulating dielectric. Materials Perhaps most important in creating a zero-loss cable is the choice of conducting materials within the cable. Unfortunately, there are no perfect conductors of signal. Each material has its good and bad qualities. If we were to list conducting materials in order of their ability to pass electrons it would look like this:
Silver is the best conductor in the world and copper the second best (by about 7%). The problem with  silver is the cost: solid silver sells for $125 a pound while copper sells for less than $1 per pound. To try and take advantage of silver’s conducting superiority, while keeping the low cost of copper, many cable manufacturers have turned to silver plated copper. While silver plated copper can be good, it isn’t the best because silver plating makes worse a property of electrical current known as skin effect. Skin effect Skin-Effect is one of the most fundamental problems in cables and it means that current density diminishes at distances away from the surface on the inside. Think of a metal conductor as a rail. Electrical energy is transferred as current inside a metal conductor and as a magnetic field outside the conductor. The only place that both magnetic field and current fields are 100% relative to each other is at the surface of a conductor. Inside the conductor they are not equal. Skin-effect causes different audio frequencies to encounter different electrical values (reactive and inductive) at different distances from the surface of a conductor. The result is that some of the delicate high frequency information, the most important part of musical reproduction, will be smeared (not arriv  ing at the same point in time). When you plate one material over the other you have, in effect, two “skins” and high frequencies can sound either dull or irritating depending on materials.For no-loss audio performance you need a pure conductor of either copper or silver. Not everyone can afford solid silver, so when we designed the xStream Audio line we knew it was important to offer an alternative to silver; and copper is the obvious choice. Copper comes in many forms and our investigation led us to its purest form, PCOCC. Copper types The key elements that determine a conductor’s performance are: purity of material and the number of grain boundaries. A grain boundary is the meeting point between two grains or crystals of metal. Grain boundaries tend to scatter and impede the flow of electrons and act as a non-linear resistance to the flow of electric current. With fewer boundaries, the less the effect on an electric signal as it propagates from one end of the conductor to the other. What we want is a single grain, which has essentially no boundaries. Solid silver has very few grain boundaries while copper, depending on how it’s formed, tends to have thousands of grain boundaries. We can break down the different types of copper used for conductors into four groups, each with a descending order of grain boundaries:
TPC is the name given to unprocessed copper: the type usually employed in your home’s power wiring and  inexpensive audio cables. TPC is melted once and formed into a cylindrical shape which is then repeatedly pulled through a small opening to reduce it to the desired diameter. TPC contains high oxygen and impurities content and is not suitable for high performance audio. These impurities contribute to an increase in grain boundaries.OFC OFC was developed in Japan around 1975 in an attempt to decrease the oxygen and impurity content of TPC and reduce the number of grain boundaries for improved performance. It is produced in an oxygen-free-inert-gas atmosphere. This leads to an improvement in conductivity between 0.5% and 2% greater than TPC because there are fewer crystal boundaries present to cause signal degradation. OFC is used throughout the high end audio industry and is a good sounding conductor. LC-OFC LC-OFC was also developed in 1975 by Hitachi to improve the performance of OFC. It is made in the same way as OFC, but an additional step re-heats the copper wire, which reduces impurities between the crystal boundaries as the copper crystal grows and leads to a longer grain length. A typical grain in a 1 millimeter diameter LC-OFC conductor is 6 inches long, compared to only 1/100th of an inch long grains in TPC or OFC conductors.  PCOCC In 1985, a method for the extrusion of a grain free copper wire was developed by a Professor Ohno. Known as The Ohno Continuous Casting Method, it is very similar to LC-OFC but the forming equipment re-heats as the molten copper is forced out of the mould and very slowly draws the grain down the conductor's length, creating a 'single grain structure'. It has long been known that heating a metal increases the length of the grains within the metal and since the early 1970’s copper wire has always been continuously cast for economic reasons. It wasn’t until Professor Ohno combined these two principals together that we can enjoy the benefits of boundary free conductors. A typical single grain in a PCOCC conductor is 350 feet long! Compare that with 6 inches for LC-OFC and 1/100th of an inch for TPC and OFC. PCOCC is nearly ten time more expensive than OFC and difficult to purchase as there are relatively small quantities made at any one time. The Reference Series With almost no grain boundaries whatsoever, the PS Reference Series comes as close as copper can to our promise of a no-loss line of audio and speaker cables. Perfection of the connectors, the shielding and the materials create an exceptional, low-loss interconnect. The Transcendent solid silver Series Solid silver, with its lower resistivity and higher conductivity, is the best known conductor of both electricity and heat in the world. 7% better conducting properties than the best copper, it has naturally occurring long grains with few boundaries to impede electron flow. Another interesting feature of silver is how it oxidizes, relative to copper. When exposed to air, both copper and silver “tarnish” (oxidize) and the resulting material is known as copper or silver oxide. Copper oxide is non-conductive while silver oxide is a very good electrical conductor. This oxidized layer sits on the surface of the conductor and, in copper, causes time smear due to the skin effect we discussed earlier. In silver, there is less of this effect because the oxidized layer is conductive. Creating a low-loss cable out of solid silver is an economic challenge as any conductor, whether silver or copper, must have a reasonable cross sectional area when used for audio applications. Because silver is so much more expensive than copper, most solid silver cables have minimal diameter conductors to keep the cost low (28 gauge is fairly common). We have seen tiny, thin wire gauges of silver in some products that lose a lot of information in the bottom end. This makes some solid silver cables sound bright and edgy; but in reality, they are simply missing the lower end of the musical spectrum. An appropriate amount of silver or copper in an audio interconnect is 1mm, or the equivalent of 18 gauge wire. Both the Reference PCOCC design, as well as the solid silver Transcendent Series use a double 1mm diameter solid core conductor to carry the musical information with as little loss as possible. One for the ground, one for the hot, and then a full shield around the cables. This permits the fullness of the bass, naturally occurring in your music and equipment, to come through unimpaired with all the fullness and richness your system has to offer. The xStream Audio Cable Series Our goal was to build audio interconnects of such purity and attention to detail that an absolute minimum of information was lost when connecting your equipment together. We achieved this goal by using only the best connectors, the best shielding and the finest materials in the world for conductors. Connectivity of equipment is the foundation of a good system. You can spend a lot of money buying the best equipment in the world, but if you cannot connect it such that all the information available from your components gets to your speakers, then you’ve reduced the value of your investment. Once you audition one of these fine cables in your system and hear what your former cables have been holding back on, you’ll be delighted and in awe. Visit your local PS dealer, E-tailer or PS if you live outside of a dealer’s area for the finest interconnecting cables in the world, at any price. Ready? The new xStream Resolution Series is shipping now. You can contact your local dealer or distributor, click here, or call us at PS and we'll make sure you're one of the first to find out just how great your system can sound. Don't let this opportunity pass you by. |
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