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Positive Feedback ISSUE 67
A Complete Suite of Cables!
as reviewed by Guido D. Corona
Always keen in maintaining a systematic approach in my cabling reviews, so to maximize synergy among components, I was delighted to be given the opportunity of evaluating a complete loom of reference cables by Aural Symphonics. The review suite consists of three 2 meter long Magic Gem power cords terminated with 15A IEC connectors, two 3.5 meter long Ultra Cube XXV power cords ended with 20A IEC connectors, three sets of 2 meter long Chrono B2 XLR balanced interconnects, and one pair of single run Chrono (non balanced) speaker wires finished with spades and banana plugs.
Tommy Dzurak, President and CTO of Aural Symphonics since its introduction, is rightfully proud of his craftsman's approach to the art of creating cable products for high-end audio applications. In a recent phone conversation, Dzurak shared with me some of his experiences, design philosophy, performance goals, and technical solutions. He asserts that he has Changed expected norms of cable construction into methodologies applicable to the manufacturing of custom hand-made cable products that satisfy the advanced requirements of audio enthusiasts.
In the Aural Symphonics workshop, through years of extensive signal analysis, and by applying his own discerning sensitivity as a dedicated audiophile, Tommy has evaluated and tested a plethora of cable geometries, configurations, metallurgies, manufacturing processes, as well as the mutual advantages and disadvantages of building machine-manufactured cables versus hand-made products.
Aural Symphonics's very first cable was a largely machine-made interconnect called the AS-ONE interconnect. Yet, for the last ten years, with the exceptions of digital coaxes, HDMI, glass fiber optics, USB cables, Dzurak has ESCHEWED total automation, and has mostly produced cable products that harness the precision afforded by automated basic conductor manufacturing, combined with the freedom afforded by a craftsman's approach of geometric configuration, choice of materials, and final cable assembly. He explained how his adoption of the artisanal approach to cable production is not one of Luddite rejection of factory automation. Rather, he became concerned that the extant processes and materials employed in much automated cable manufacturing were counter to his ultimate goal of instilling a consistently clear and revealing musicality to his product line. In particular, he observed that in machine-made wire products, to achieve a perfectly round cable, crushed polypropylene was being inserted as filler. Strands of thickish polypropylene filaments were intermeshed with conductor strands and wires. These supposedly inert strands fill residual empty gaps in the cable, and help to yield a perfectly round cable profile, no matter what the cable's internal geometry may be. However, he soon discovered that unintended electrostatic properties of this type of filler caused veiling of images, blurring of harmonics, AND OVERALL dulling of that very detail which makes music alive.
Tommy notes that the creation of a new cable product is not only a lengthy process, but can be a surprisingly expensive proposition as well, particularly for cables that are entirely machine-made. The designer may initially need to purchase thousands of feet of any highly customized wire from a dedicated wire house, because most wire houses enforce minimum purchase quantities for custom orders. Invariably, the cable designer builds a large number of prototypes. Regrettably, most of these prototypes do not meet the sonic and musical goals of the creator: they are found to be unsuitable, and must be written off as R&D (research and development) expenses. Only those rare prototypes that meet all design goals eventually become products.
Today, Aural Symphonics takes advantage of manufacturing automation for underlying conductors, combined with an artisan's approach to finished cable construction. Basic wires are drawn and manufactured by dedicated wire houses, where they are also insulated with dielectrics.
All Aural Symphonics Wires and connectors are then cryogenically processed through a proprietary 72-hours long cycle. While the very first Aural Symphonics product was based on Silver-coated copper, today Tommy Dzurak prefers to harness the properties of readily available 99.99% pure Oxygen-free Copper, which is cryogenically treated through his company's cooling and recovery cycle. He reports that treated wires show enhanced conductivity and mechanical stability. He adds that the Sound of cryogenically treated conductors is clearer and airier, and is inherently superior to any Silver-coated wire. Furthermore, Because of his unique cable architecture, Dzurak believes that cryogenically treated 99.99% Oxygen-free Copper in his products outperforms any untreated 7N or even 9N exotic Copper wires.
Dzurak declines to discuss specific gage sizes: Gage by itself does not determine the total performance of a cable—he explains. However, Tommy admits that smaller gages enhance high frequency clarity and performance, while larger gage wires yield warmth, more midrange, and better bass definition. Aural Symphonics ESCHEWS litzed wires: according to Dzurak, litz coating yields an unnatural bloom; it blurs fine detail, and accentuates the midrange to a "Gloriously tuby" sound, which falls unfortunately short of realism. If he used a litz conductor, he would be forced to parallel it with a Silver, Silver-coated Copper, or pure copper solid core, so to compensate for the speed and dynamics degradation caused by the main litzed conductor.
Dzurak continues that inductance yields potential problems for any cable that has a positive conductor that creates an electro-magnetic field. For this reason, he minimizes capacitance and mutual inductance by conductor design, and by regulating the spacing between wires using a variety of PVC fillers and conduits, thus avoiding the detrimental electro-static effect of polypropylene. Today, instead of using crushed polypropylene fillers, Aural Symphonics regulates distances between conductors by housing wires into corrugated PVC conduits, which are then bundled and then inserted into larger slotted tubes.
Finally, cables are jacketed with industry-standard nylon weaves. As snug jackets can render large cables stiff and unwieldy, Dzurak prefers to use nylon jackets that fit comfortably loose.
Tommy seeks to achieve refined musical neutrality across the frequency spectrum. Cables are simple circuits—he declares. Throughout the years, Aural Symphonics has developed more than one unique cable circuit topology to foster its sonic goals. Not unlike with bypass electronic capacitor configurations, where a small polypropylene cap is connected in parallel on top of a larger electrolytic capacitor, some of Dzurak's cable designs, such as the single-ended Chrono speaker wire in my review suite, feature a smaller conductor connected in parallel to a large positive phase conductor. Tommy explains that this solution enhances the ability of the cable to reproduce a clearer, more open, and more transparent audio signal. In some design variants, the smaller gage parallel conductor may be folded back and forth onto itself to achieve a product where sonic tuning is based on timing, and on the further regulation of mutual induction between conductors.
In other products, like the Ultra Cube XXV power cord, Dzurak adopts his own patented floating conductor configuration (US4754102 - Directional interconnection cable for high fidelity signal transmission ). Four wires are selected; all conductors at the source end are connected, but at the destination end only three conductors are connected. The fourth wire is left to float, and operates capacitively to the main bundle of three wires. Tommy explains that the selective combination of parallel and floating conductors, together with a variety of other techniques that he incorporates in his products, enhances the performance of cables and renders their behavior invariant to length: "A 24-foot long Aural Symphonics cable sounds as good as a 1-meter long cable", He declares.
The Chrono (non-B2) speaker cable in my review suite is an unbalanced design. The positive signal is served by a large positive conductor paralleled by a smaller conductor, while a unique smaller-gage conductor carries the return signal. As in all current Aural Symphonics cables, the Chrono speaker wire is not shielded, and so sports very low capacitance and inductance. The all-Copper conductors are spaced as far apart as possible, by running them inside individual PVC tubular conduits that are then bundled and inserted into a large jacketed slit conduit, achieving a total impressive diameter of almost 1.75 inches. The wire is terminated with Rhodium-plated Cardas spades at the source end and Aural Symphonics own banana connectors at the speakers end.
The Neutrik-terminated Chrono B2 XLR interconnect is a unique unshielded design based on stringent requirements for long snakes used in pro-audio applications: very low capacitance and inductance, and negligible signal loss over great lengths, up to 100 feet. Chrono B2 XLR features three conductors: two identical large conductors for inverting and non-inverting signals, and a smaller conductor for the return signal.
Tommy Dzurak believes in making power cords that are true high performance generalists, designed to excel in high power, low power, and very low power digital applications alike. The Magic Gem in my review loom is Aural Symphonics's reference-grade power cord. The product is not derived from any preexisting signal wire, but is a pure AC design, consistent with the philosophy of creating specialized reference products for each application. Magic Gem sports three conductors of different gages, each tuned to its particular purpose: positive, neutral, and ground line. Through line disturbance analysis, Tommy has determined that EMI and RFI noise plaguing electric grids penetrates mostly through ground lines. Thus, Magic Gem, as well as other high-end Aural Symphonics power cords, filters out such harmful grunge from the system by the application of frequency-tuned ferrite cores that are mounted onto the ground conductor. Magic Gem cords are terminated with a Wattgate IEC connector and a Wattgate AC mains connector, or with a Furutech AC mains connector upon request.
As I pointed out in previous articles on cable products, technical design and construction principles invariably constitute fascinating discussions in the abstract, but unless applied technologies correlate positively to musical results, the designer's effort is for naught. Thus, I was quite keen to verify the sonic prowess of the cable suite, under a variety of equipment configuration. Over the last 12 months, my evolving test environment has consisted of an Esoteric K-01 and X-01 CD players, the Rowland Criterion Preamplifier, an early version of the Rowland M625 300W stereo amplifier, a pair of Rowland M725 330W monoblock amplifiers, the amazing Merrill Veritas 400W monoblock amplifiers (review upcoming), and the marvelous quasi 5-way Vienna Acoustics The Music—my reference speakers (reviewed PFO Issue 59).
Aural Symphonics Chrono XLR interconnects are mercifully flexible and easy to work with, and their connection is a breeze. Conversely, the much thicker and heavier Magic Gem and Ultra Cube XXV power cords, as well as the Chrono speaker wire, offer some moderate recalcitrance before they yield to being wrestled into place.
I am used to lengthy break-in processes: I have experienced cable break-ins protracting up to the one-thousand hours mark. Yet, according to Tommy Dzurak, the cryogenic treatment and geometries in Aural Symphonics products should let the cables require little or no break-in time at all: the wires would sound their best shortly out of the box—he assured.
Reality fell somewhere in between Tommy's proud optimism and my own dour predictions: with the Rowland M625 stereo amplifier inserted in the system, after approximately 300 hours of maturation, the Aural Symphonic suite achieved an impressive sonic adulthood.
Interestingly, after only four hours of break-in, Stage and image size already reached the proportions that I was seeking. By hour 12, an initial center hole in the 11-foot wide stage had filled in, leaving no appreciable traces. Simultaneously, the initially two-dimensional stage had started to deepen, and the bass was showing the first signs of that harmonic development which appears to be a hallmark of a mature Aural Symphonics house sound.
Twenty-four hours into the process, transient hardness abated for the first time in the high split octaves of Inna Poroscina's masterly performance of the dynamically intense miniature for piano "In The Old Castle" by Antonin Dvorak (Brilliant Classics redbook). The introduction to the first movement (Allegro Moderato) of Dvorak's string sextet with double bass Op. 48, performed by Members Of The Berlin Philharmonic Octet (Philips Classics) is a sonically challenging affair, where the rising and growingly dynamic harmonies of the pre-thematic cadenzas induce many mature cables to generate strident intermodulations. Yet, Aural Symphonics wire were showing early signs of their hallmark future abilities: stridency was already contained to moderate levels, and further abated throughout the break-in process to a negligible point, whenever the Veritas monoblocks or the Rowland M725 were inserted into the system.
At an even earlier stage, I had observed a slight attenuation in the treble combined with the transient strain, which caused massive piano chords, arpeggi, string vibrato and micro-transients, to sound simultaneously slightly filtered and marginally brittle, falling short of an ultimate vibrancy and emotionality. Those very low levels swishing of felts and creeks of piano mechanics, which I had known to be present in the Poroscina recording from my prior experience with the delightful Furutech Evolution II wires (see my review on PFO No. 45), and with the stunning Shunyata CX and Z-Tron series, were not yet in evidence. Similarly, deep base was attenuated, with Edgar Meyer's double bass rendition of J. S. Bach's Prelude from the Suite No. 5 (Sony Classics) to sound light and almost "celloish". Yet I should have feared not: the necessary foundational growl of the string bass, as well as the low-level extra-musical information in Poroscina's performance, gradually blossomed throughout the break-in process.
Undeniably, during their sonic childhood, for the first 100 hours of music making, there was an almost imperceptible haze over the music… I wondered, in a sudden attack of audiophilic anxiety, if perhaps Aural Symphonics wires are inherently not up to the task. Yet once again, I should not have fretted: in due time, the wire loom rewarded me with a fine transparency that blossoms in evidence.
One encouraging sign during the later stage of break-in was the low brass fanfare that introduces the 2nd movement of Dvorak's New World Symphony, performed by the Israel Philharmonic under the baton of Leonard Bernstein (DGG): a powerful cuivre concludes this sonically challenging passage, which, under other wires, has resolved into a painfully jarring jumble. Rather, Dzurak's wires yield one of the most artifact-free renditions that I have heard in my system. Particularly with the Rowland M725 or the Merrill Veritas monoblocks in the circuit, the loom eventually delivered a surprising grandness and gravitas.
As break-in progressed, dynamic authority blossomed in the Dvorak short piano piece, as well as in the New World Symphony. Cuivre morphed into an almost structural musical element in brass choruses. The piano treble opened up, while acquiring body and image placement. I gradually became aware of a more fleshed out harmonic development in all musical selections, while string bass lines became increasingly present, deeper, and harmonically congruent. Felt and pedal noise developed into Poroscina's performance, where the high 7th in the final arpeggio gradually acquired musical substance, and the complex interplay of decaying harmonics in the final chord could be heard until the last second of the track. The introduction to the string sextet grew in grandness and solidity: a trace of mid-bass ripeness was but a temporary affair, which appeared around the 100 hours mark, but soon faded out during the second week of listening.
Break-in lasted a scant two weeks, for a total of perhaps 300 hours of continuous playing time on the Esoteric K-01. Unsurprisingly, the first 50 hours were filled with the usual cycling of subtle performance inconsistencies, mildly distorting artifacts of one form or another, and inevitable sonic fluctuations. Yet, by the end of the second week, it became clear that the Aural Symphonics cables are exceedingly solid performers characterized by a fine neutral musicality, capable of exposing the unique personalities and relative strengths of the interconnected componentry.
With mature Aural Symphonics wires, mid-treble glare is uncommon, and appears to be confined mostly to intensely dynamic chordal passages, while high treble is typically textured and extended. Aural Symphonics does not induce major bass overhang, which my bass-happy Vienna Die Muzik speakers can generate if not tightly controlled. An occasional bass excess or wooliness appears to be mostly a function of specific recordings, as can be shown by comparing the somewhat romantic string bass line in the New World Symphony already discussed, against the marvelously taught bass part in the single adagio movement of Gustav Mahler's 10th Symphony, as performed by the Bavarian Radio Symphony Orchestra under Rafael Kubelik (DGG reissue). Regardless of music selection, Aural Symphonics wires consistently reach comfortably deep into the low frequency region, and remain textured throughout the spectrum. Inna Poroscina's piano confirms it: the review set reaches deep into the sound, with satisfying Low-level information and detail, ever accompanied by a ripple of decaying harmonics; I detect even the infamous noise from the air conditioning equipment in the recording venue—during the vanishing sostenuto ppp of the last 10 seconds of the track. The delicately breathy voice of Norah Jones, in her delightfully retro rendition of Sinking Soon from the 2007 redbook album Too Late now, conveys subtle humor and expression, together with imaging solidity. The plucked string bass in the work is essentially linear and well-pitched, and assumes an authority that the mid-priced Furutech wires only alluded to.
Anton Bruckner Symphony No. 4, performed by the Austrian Radio Symphony under the direction of Milan Horvat (Musica D'Oro reissue, May Audio) is majestic. Aural Symphonics wires transmit the passion, drive, gravitas and cultural understanding that I expect from a major performance of this work. Particularly when the Rowland M725 monoblocks or the Merrill Veritas are supplying power amplification, Tommy Dzurak's creations yield a solid sound stage with proportions that range from a realistic 13-foot to a vast 16-foot wide span. Invariably, instrumental sections are placed correctly in the 3 dimensions. Woodwinds do not rush suddenly front-stage during solo passages, but are anchored to their correct spatial perspective. Brass choruses are massive and powerful, yet their cuivre seldom peaks into shrillness. The wires allows Bruckner's complexity of orchestration to emerge, as subtle melodic lines of hidden instrumental voices in the middle range reveal themselves in sudden and especially delightful moments.
While perhaps shy of the performance peaks that I have experienced with the more expensive Shunyata CX and Z-Tron wires, Tommy Dzurak's cables solidly congrue with that elusive Goldielockian principle that I always seek—an eminent musical neutrality, where images remain centered on a large stage; where vocal plosives are contained; where the treble is extended without a metallic sheen on overtones; where the midrange is harmonically textured but not forward, and where the bass is deep and pleasingly tuneful. Dzurak's cables bring to my system a fine resolving power, with the neutral musicality that is synergistic with my components and with my musical goals. They do not overdrive the Muzik speakers with subtly distorting intermodulations or excessive energy in the treble region, nor do they artificially emphasized leading edges of micro and macro transients. Their bass does not trade authority for facile speed or an unpitched thump, but tends to deliver a solid sense of textured pitch. The Aural Symphonics soundstage is inherently broad, and enjoys a front-to-back centeredness, which neither is recessed nor is it forward.
Since the addition of the Vienna Die Muzik speakers to my system, Tommy Dzurak's wires have proved to be very fine achievers, and have been my cabling reference for over a year. The complete loom has demonstrated a broad-spectrum of fine sonic and musical reproduction abilities, without major artifacts. In final analysis, I can comfortably state that the Aural Symphonics Magic Gem and Ultra Cube XXV power cords, the Chrono XLR interconnects, and the Chrono speaker wires are capable of yielding an enviable cabling reference point in many reference-level audio systems. Guido D. Corona
Chrono B2 XLR balanced interconnects
Gem V2T power cord
Ultra Cube XXV power cord
Chrono speaker wires (single run, unbalanced)