What do you expect from a speaker cable? Think about this for a moment and I am sure that you will find it in today’s very crowded cable marketplace. It seems that a new cable company is literally popping up every day to offer you their version of the best. “The Best” could be the best sound they can offer or the best value for the money. Less visible is the routine disappearance of these fledgling companies as their version of perfection is dismissed by you, the buying public.
Of course, it is hard for these companies to get your attention. And very few of you want to be the first one to buy something and get stuck with a loser, one that gets bad press and its resale value drops like a jet plane whose engines have flamed out. It should be obvious that PS Audio has been doing enough of the right things to enable them to stay in business for many years. Those “right things” usually are offering good sonic value, good quality, and good support. Of course, a hefty marketing budget helps tremendously to “get the word out” and also facilitate reviews with demo gear.
Over the past couple of years, I have tried their xStream Plus and Statement interconnects and speaker cable. (I also auditioned some of their power cables, but that is a subject for another review.) I did not really care for the earlier speaker cables or interconnects, feeling that while they provided decent sound, they were too colored to approach reference quality at their price levels. The Statement improved on the Plus series by reducing a small but noticeable level of haze (it was too fine an obscuration to be called “grain”), but suffered from a soft, billowy, unfocused character. Like EL34 tubes compared to KT88s or 6550s. Relatively speaking.
Technically, the xStream Resolution Reference speaker cables are 8 gauge cables using PCOCC (Pure Copper by Ohno Continuous Casting). Copper has a crystal grain structure, and reducing the number of grains, which reduces the number of distortion-inducing boundaries with the next grain, helps the sound quality to a large degree. In the PCOCC cables, a typical single grain is 350 feet long. Imagine a grain of rice that is 100 meters long! (Now imagine the chop sticks you would need to pick up that BMF!) Compare that with 6 inches long for LC-OFC (linear crystal-oxygen free copper) and 1/100th of an inch in common oxygen free copper (OFC). The important dielectric is polyethylene foam, which is mostly air. The best dielectric is a vacuum, but since we are planet-bound, we will have to settle for air. The cost is $800 for a 3m single wire pair and $1280 for the same length in a bi-wire configuration. There is also an all-silver version called “xStream Resolution Transcendent” for $4k. It uses pure silver instead of copper, but is otherwise identical to the Reference model.
The character traits I noted for the Plus and Statement are absent in the xStream Reference. And I don’t mean that the Reference cable is just an incremental sonic improvement over the earlier models, patching one problem or fixing another. I mean that the good ears at PS Audio apparently recognized the weaknesses of the Plus and Statement cables – which have been discontinued – and designed their new cable without these traits.
There is no hint of soft and undefined bass. The Reference cable offers excellent punch and power in the bass, with a perfect balance of pitch and definition. Bass reproduction in any component is very comparable to a sealed-box woofer. Very low Q systems (around 0.5), have great detail and definition – and a much larger box – while trading off some leading edge impact. Higher Q subs (around 0.9 or so) have very good kick-you-in-the-stomach punch but with much lower “see the strings vibrating” definition. It is the same with speaker cables. I equate the Reference cables with a Q = 0.6 bass system, which, in my experience with many subwoofers, both commercial products and DIY, is about the perfect spec for excellent power and impact and outstanding speed and resolution.
The upper bass and lower midrange, where most of the male voices live, has a natural richness that gives great focus and depth to voices like Mark Knopfler’s and Eric Clapton’s. Clapton’s gravelly voice comes through with great presence without sounding distorted, as lesser components can do to his complex voice. In orchestral music, the xStream Reference makes it a simple task to pick out each type of string instrument. Bass, cello, viola, and violin have clear and distinct sonic signatures that are quite noticeable through this cable.
Where “the rubber hits the road” (an automobile reference meaning when performance becomes critical) with almost all gear is the upper midrange and lower treble. Many readers report that while they can adapt to or ignore minor problems in the lower frequencies, the range of female vocals must be near-perfect or long-term enjoyment suffers. I am especially aware of problems in this area, which is one reason why I find component break-in to be a critical step to complete the installation of a new component. The PS Audio cable does not do anything obvious in this important frequency range, which is exactly what we want from any great audio component. It simply passes the signal, rich, vibrant, clean, clear, and engrossing, without anything added. No detail is missing, or more commonly, no grain, brightness, spotlighting or other distortion is added. This benchmark-setting lack of character clearly showed that the former reference cable, Acoustic Zen Satori, has a subtle coarseness and attendant emphasis in the upper midrange and lower treble.
The upper treble follows perfectly. Details are clear but never unnaturally highlighted or forced. There is an obvious difference between ‘60s early solid state studio recordings and recent audiophile vinyl, and one of the benefits of these cables is letting you hear great recordings sound great. There is no attempt to offer pleasant mass-market sound, the equivalent of today’s “reality” shows (which are actually anything and everything but “real”). The xStream Reference cable is brilliant in its absence of character. The result is that the rest of your system must do its job properly or you will be disappointed. If you want a tone control, look elsewhere. Soundstaging is as visually exact as I have ever heard (seen?). Layering, depth, width, and individually specific instruments and voices set a very high standard. There are no problems or concerns in this area. Virtual reality, after about 150-200 hours of break-in, is common. Here’s the take-away: From the low bass to the ultrasonic, xStream Reference is entirely transparent and naturally smooth, with a level of detail that defines “reference grade”.
The cable is usefully flexible for being a large garden-hose size cable, and the bend radius is about 4 inches. The break-out, where the positive and negative leads are separated from the covered cable, is a beautifully finished, high quality metal casting. The soft synthetic fabric outer cover is a nice touch, especially after living with and handling the common TechFlex® type nylon mesh jackets of many other products. It seems to be a bit more susceptible to abrasion, however. The amplifier and speaker connections in my prototype samples were screw-on spades or bananas, and they were somewhat fragile. The very approachable Paul McGowan has assured me that the design was changed in the production cables to a more reliable fixed connection.
xStream Resolution Reference cables easily meet the requirements for the designation “reference-quality”. They are perfectly linear, have very powerful and detailed bass, a tactile human midrange, and exceptional smoothness in the upper frequencies but also with apparently limitless low level detail. SOTA sound staging. These speaker cables are neutral. It is easy to recognize a product that has some character, such as the loose “billowy bass” above, or a forward treble, or an undefined soundstage. It is much harder to “know a good thing if it bit you on the nose” as the saying goes. Bad gear is easy to identify, but really excellent gear sometimes takes a long time to convince you of its true glory. Give this cable a try. You will love it. I do.
Overall Rating: 10 LPs
Link to manufacturer’s Web site: PS Audio