Product Review - Nordost Flatline SPM Reference - November, 1996

By John E. Johnson, Jr.


SPM Reference in Box

Nordost Flatline SPM Reference; Interconnects and speaker cables; Interconnects: Eight 24 gauge conductors per leg (16 per interconnect); Copper with silver coating; Teflon dielectric; Terminated with RCA plugs; $1,100 per meter pair; Speaker cables: Configured for bi-wiring; Four sets of eight 24 gauge conductors; Copper with silver coating; Teflon dielectric; Terminated with banana plugs or spade lugs; $3,200 per 8 foot pair; Nordost Corporation, 420 Franklin Street, Framingham, Massachusetts 01701; Phone 508-879-1242; Fax 508-879-8197; E-Mail [email protected].

When I first encountered Nordost Flatline cables several years ago, their only product was Flatline, which has four conductors per leg (eight total per cable) and now sells for $3.49/foot. With a Teflon dielectric, this cable is a landmark design and sounds great. Nordost quickly increased their product line to have numerous models, including Blue Angel, Blue Heaven, and Red Dawn [click here to see review in Secrets].

Now comes SPM Reference, Nordost's finest cable to date. At first, I thought SPM was outrageously expensive, but after looking at the prices of other high-end cables in one of the component guide issues of another magazine, I discovered that SPM is in the middle of the price range! As you can see from the photo, SPM is flat, like most of Nordost cables, being about 2 mm thick. With the interconnects, there are eight 24 gauge conductors in each leg (total is equivalent to 15 gauge in each leg). Each conductor is coated with 60 microns of silver (by extrusion, not electroplating) and is insulated from other conductors by Teflon. Each conductor is spaced 0.050 mils (edge to edge) apart. The same is the case for the speaker cables, except that they are configured for bi-wiring or bi-amping. Having conductors side-by-side instead of twisted together or arranged in a helix, produces low capacitance (6 pF/foot) and inductance (0.07 H/foot) values in the Nordost. The resistive impedance (1 Ohm/1000 feet) is low, but just about any audio cable has a low DC resistance. It is the reactive impedance values (capacitance and inductance) which vary quite a bit between different brands of cables, and which, when high in value, can affect the sound significantly. Since the Nordost line has the conductors side-by-side, the profile of individual conductors facing each other is small, and the outside conductors are far apart. Thus the low reactive impedance values.

SPM has a slight violet cast to the Teflon, but the silver/copper conductors are obvious. The 60 micron coating of silver is put onto the copper during the extrusion process (sort of like using a pasta machine), rather than an electrochemical plating. The Teflon is part of the extrusion process, and the result is not only an airtight seal between the Teflon and the conductors, but the atomic structure of the interface between the silver and copper is different than it would be with electrochemical plating. Because of extrusion, the copper and silver form, more or less, two continuous crystals of copper and silver metal along the length of the conductor. When the finished cables are flexed or bent at a sharp angle, these crystals will be disrupted, and "grain boundaries" or "faults" result. The attached figure, courtesy of Dr. William Krakow, Peekskill, New York, shows the grain boundary between gold crystals at ultra-high resolution (magnification about 1 million depending on the configuration of your computer monitor). You can see that the gold crystals have a very precise lattice of gold atoms (spacing between atoms is 2.3 Angstroms), but that the grain boundaries represent a disruption in the otherwise continuous lattice that would have been present if there were not any grain boundaries. Such boundaries could be considered to be similar to having multiple conductors laying side-by-side and touching one another. The trend in high resolution audio cables these days is to have individual conductors insulated from one another. Thus, cables like these, where so much effort has been put into making them single crystals, should be very carefully handled . . . not bent at sharp angles, not creased, and not stepped on.

When we put the SPM into our reference system, we noticed an improvement in the amount of musical detail that comes through. Triangles, for example, are always recorded at a very low level, because they can be piercing and overwhelming otherwise. Unfortunately, the detail of this instrument can be lost through jitter or mediocre cables. Even with the amplifier set at low volume, the tinkle of this instrument was right there. Detail seems to emerge from a nebulous background. The bass, mids, and highs were not emphasized compared to our Red Dawn, but there was definitely an increase in the clarity. We could even hear the little metal rod used by the percussionist to strike the triangle. The pluck of violin strings, the tap of castanets, the click of trumpet keys, all moved into the listening room. It was almost the same effect as adding a good outboard DAC to a CD player or putting a jitter reducing component in the signal chain. I should say that these cables are not intended for any but the very finest electronics and speakers. The SPM made our Anthony Moore Ribbon speakers and Osborn Eclipse's just sing like a meadow lark. The failings of a few of our CDs were also apparent, and we are discarding them. I can't wait for the new 24 bit 96 kHz CDs to become a reality. Remember when CDs first came out, and we all (well, many of us anyway) thought that audio nirvana was here? Now, they have some catching up to do.

Five thousand bucks is a lot for about 40 feet of wire. Why so much? Apparently, the extrusion process is extremely difficult, and there is a lot of waste. The materials cannot be recycled or repaired. They have to be just thrown out. It is not like testing an amp off the assembly line. If a capacitor is bad, it is replaced, the unit retested, and if all is OK, it is shipped. With the Nordost process, if there is a break in the silver coating, if the conductors are not spaced exactly to specifications, if there are any kinks, the entire cable has to be discarded. This, plus research costs that went into developing the proprietary methodology, makes the cables expensive to manufacture. Add the profit margins for the manufacturer and dealer, and there you have it . . . high cost to us (basically about 4 times the cost of manufacturing).

These cables are as beautiful to look at as they are to listen to. They come in a special wooden box with a laser engraved logo. My wife took the box, covered the logo with a piece of painted ceramic, and voila . . . a jewelry box for her dresser. So, the SPMs are like a fine meal. The presentation is part of the pleasure.

All of the Nordost cables use the same banana plug now. It is a single slotted tube of gold-plated copper that is tapered so that it fits tighter the more you push it into the jack. It is very nice, and we plan to replace all of the banana plugs on our Nordost reference cables with this new plug. The RCA jacks on the SPM are similar to those on the Red Dawn, with an outer sleeve that retracts as the plug is inserted into the jack.

In summary, I am amazed at how cables are getting better and better, although at a hefty price. The SPMs are already very hot items in parts of Europe and the Pacific Rim, with glowing reviews coming shortly from several (other) audio magazines. Whether cables of this price level will be just as hot here in the States remains to be seen.

John E. Johnson, Jr.

Copyright 1995, 1996, 1997 Secrets of Home Theater & High Fidelity
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