A singular way of "reducing distortion caused by electromagnetic forces and current flow" in audio cables.
erhaps I’m old school for thinking that the job of an audio cable is to pass a signal from A to B without manipulating it or losing some part of it along the way. Nowadays there may be as many cable-related sonic differences as there are cables themselves. To me, it seems odd to select a preamp, amplifier, and speakers then go looking for cables to adjust or compensate for their sound. After all, no one does it the other way around.
An amplifier modulates the flow of current coming from the wall via its power supply using a low-voltage signal coming from a source as its guide. Should the wire the amp uses to send its output to the speakers further modulate that signal? What would guide that process? Cable designers play with different wire geometries, metallurgies, insulation, connectors and such, and most are adept at tuning their wares to fit within a multitude of cable families and price tiers. The market churns out new models on a regular basis, requiring differentiation from all the other cables, and feasts us with a diversity of coloration. Will the plethora of audio cables ever collapse into a singularity of unaltered signal transmission? Would we gauge that as progress? Despite the occasional cyber-mob ranting about reptile lubricant, the reality may be boring. It’s easy to say tiny steps mark progress in audio cables because the universe is obscure and its problems are difficult to understand. Yet I can’t help wondering if cable design has been stuck in a bubble, waiting for a breakthrough. Louis Motek, the director and chief designer for LessLoss Audio, thinks recalcitrant problems could just as easily be characterized as questions asked in the wrong way, while the mere fact that there are so many different-sounding cables strongly suggests that many of the right questions have not yet been asked. Magnetic electric -- star-crossed lovers on a tunnel bridge
essLoss Audio is a small company with its roots in Lithuania. As a child of the Internet (rather than a bricks-and-mortar refugee), LessLoss leverages its international presence through an online storefront that features pages of product information, diagrams and user comments. The company began by designing and producing high-performance power cords for audiophiles and music studios, and then turned its expertise to signal cables and energy conditioners. I’d not heard of LessLoss until the opportunity came to review their Anchorwave speaker cables along with an interconnect that founder Louis Motek (anglicized from Liudas Motekaitis) named the "Tunnelbridge Distortionless Interconnect System." That’s the first audio product I’ve encountered with the word "distortionless" in its title and that struck me as audacious. My interest was piqued further when I learned the Tunnelbridge was an AC-powered interconnect. Whoa! What’s up with that?
Rather than focus his thought experiments on variations in electrical specifications, blends of metals or wire geometries -- the very approaches that led to a multitude of cables with differing colorations -- Motek looked elsewhere for an answer to his question. He turned his attention to a physical force more powerful than gravity, one largely unavoidable in the context of audio signal transmission: the force of electromagnetism. Under typical conditions, an audio signal traveling via alternating current suffers its existence in an environment of shifting magnetic and electrical forces that alter the original signal coming off a component’s output. When current flows through an insulated wire, it does not pass through the insulation, but it does interact with it. The alternating current polarizes the particles of the atoms of the insulating material (the cable’s dielectric), which causes them to shift position according to the frequency and polarity of the signal at hand. As long as the AC polarity holds, the dielectric acts like a capacitor, maintaining a charged electric field. In a sense, the dielectric retains energy as a memory of the audio signal at the point when it was polarized. As time passes, the polarity of the current alternates, taking with it the polarity of the dielectric. This "dielectric relaxation" releases the remembered energy, which induces tiny new currents within the conductor, currents that are not indigenous to the signal presently on the wire. If it’s not part of the original audio signal, it’s distortion. From the perspective of magnetism, the fluctuating magnetic field surrounding a conductor does not affect the wire’s insulation, but it does impact the audio signal by inducing forces within the wire (expressed as eddy currents) that work against the current flow, changing its density and forcing it toward the wire’s surface or skin. As the frequency of the audio signal varies, this "skin effect" causes varying resistance in the conductor, which means some signals pass more readily than others. While it’s easy to imagine these time-variant electromagnetic forces causing a temporal smearing of the original audio signal, it's also fair to say that views on the sonic impact vary among makers of specialist audio cables. Motek reasoned that a signal might avoid loss and distortion if the forces of electromagnetism did not affect it. Was that possible? He found an example in the Theory of Superconductivity. Under certain superconductive conditions, electricity can flow without an accompanying magnetic field. Could a cable design avoid the distortion bred from electromagnetism by mimicking this particular effect of superconductivity, while likewise avoiding the use of exotic and expensive superconducting apparatuses? To cut to the chase, the answer was yes. Motek found a way, and it was through the Tunnelbridge: a signal-transmission environment where electromagnetic force neutralized itself, mitigating its adverse impact on an audio signal. In a Tunnelbridge cable, the audio signal travels from one component to another across a "bridge," a 20AWG pure-silver wire wrapped in a polyethylene foam dielectric. A braided silver-plated-copper shield forms a tunnel around the insulated bridge. Thus far, that is a typical coaxial cable layout. Here is what’s different: a tiny circuit residing inside the cable clones the original audio signal, placing it onto the tunnel shield via what LessLoss describes as "a super-high-speed unity-gain buffer amplifier." As the original signal travels on the bridge, the cloned signal travels on the tunnel. The circuitry to make this happen is driven by an external power supply, but -- and this is key -- current from the power supply never touches the bridge conductor or the original audio signal. A second insulated shield wraps around the tunnel to serve as the ground connection for the cable. The audio signals on both bridge and the tunnel are synchronized and in phase. (This was no easy task to implement, considering the path to the tunnel went through the cloning circuit and the path to the bridge did not.) Because like charges on both tunnel and bridge repel -- voila, there is no electrical field (no voltage potential) between the shield and the conductor. That was the theory and design. If it worked, the wire’s insulation should no longer act as a capacitor hanging onto energy and thus no longer induce current within the bridge to distort the real-time audio signal. Dynamic changes in the conductor’s resistance due to skin effect should get resolved, as higher signal frequencies are no longer forced to the outer layer of the conductor. If it worked, here was a genuinely new approach to interconnect design. Was it truly distortionless? Was the coloration bubble burst? Listening would be the test. The Tunnelbridge system implements its power supply as a small Panzerholz-clad box with metal endcaps. On one end is a blue light that glows when the unit is plugged in and on the other is an IEC power socket with four USB connectors on either side. There is no switch, so plug in the power and it’s on. A thin, flexible cable runs from the power supply to each Tunnelbridge interconnect, attaching to a six-inch tail emerging from the interconnect just behind its RCA or XLR plug at the source component. These power cables use a regular USB connector to attach at the PSU and a mini-USB D-connector to attach to the tail. One power supply supports four pairs of Tunnelbridge interconnects. Each interconnect is clad in a tough black polyethylene terephthalate (PET) woven outer shell. The review cables were terminated with Neutrik XLR connectors. Let’s do the Anchorwave
essLoss does not incorporate Tunnelbridge technology into their Anchorwave speaker cables. Motek explained that doing so was certainly feasible but would be quite expensive due to the increased size of the internal circuitry needed to handle the kind of load fed from amps to speakers. Instead, the Anchorwave design is more traditional: it focuses on low resistance, effective shielding, and reducing the effects of micro-vibrations on signal transmission, in a cost-conscious implementation. It uses 196 strands of pure, monocrystal copper Litz wire to achieve low resistance through a massively aggregated 9AWG wire thickness per polarity. A stranded bundle offers flexibility to an otherwise thick cable, while the coating on each strand inhibits signal-impairing corrosion. On the outside, the Anchorwave is the same black PET shell found on the Tunnelbridge. Beneath it is a chemically resistant Polyolefin cover and a "high-tech conductive cloth shield." Typically, speaker cables avoid metallic shielding because the shield acts as a plate with a large surface area surrounding an insulated conductor, effectively creating a capacitor. However, the Anchorwave shield filters only frequencies well beyond those of audio signals; LessLoss claims this reduces capacitance while protecting the audio signal from electromagnetic radiation in the 10MHz–20GHz range. A key goal of the Anchorwave design was to reduce the effect of microvibrations caused by current itself. Louis explained, "Only when you kill and bury the microvibrations, while not thereby altering the signal, can the music truly come to life. That microvibrations have a negative impact on audio quality is a theory which is difficult to show physically, except when we amplify it and make these vibrations louder." He offered the example of a microphone cable attached to recording equipment, but not to a microphone. If such a cable is dropped on the floor, the impact barely jostles the wire’s electrons, but enough that the capacitance changes and a signal is born. "Just like in a microphone, only it happens to be two parallel wires instead of two parallel plates." Despite the very low levels involved, amplified playback reveals a recorded signal. From my own experience, I know there are audible vibrational effects from very small differences in tonearm bearing refinement. From room to rack to componentry, every element in an audio system finds benefit from judiciously applied vibration control. Each Anchorwave cable contains anti-vibrational nano-particle material between the core Litz bundle and its shield. Designed by LessLoss, these nano-particles range in size from 12 to 44 microns (a human hair is 100 microns in diameter) and they feature an amorphous structure that avoids hardening into a lattice formation. The purpose of the particles is to disperse microvibrations caused by the flow of current itself. Those pesky eddy currents give rise to physical vibrations within a conductor sufficient to influence the integrity of the signal it carries. While Louis was mum on the exact mechanism in play, it is typical for vibration-reducing material to burn off energy as heat. Weaving in the loom
he bullion-like heft of the Anchorwaves told me there was a lot of copper in these speaker cables. They arrived with solder-tinned ends and LessLoss included the optional Furutech FP-201 spade connectors. These long spades offered adequate strain relief once secured to the tinned wire with two setscrews. I attached the spades first to my amp and speaker terminals, then inserted the tinned ends and tightened the screws. A spades-first approach allowed adjustment for whatever axial twist the speaker cable took as it approached the binding post. Whether or not you believe termination bears on sonic performance, I’d mark my calendar to clean the connections and retighten the set screws every few months. The shortest length Tunnelbridge interconnect that LessLoss sells is 1.5 meters (almost five feet). Because of the cable’s internal electronics, the added length is meant to help avoid bends that are sharper than a 12-centimeter radius, but it also makes for a long wire. On my three-tier rack the components were close enough that the lengths of Tunnelbridge from the phono stage and CD player tended to droop down and lay on power cords and one another at the back of the rack. A dozen Shunyata Dark Field mini cable elevators performed balancing acts to rival the Wallendas as they maintained spacing between the wires. Six meters of Tunnelbridge ran from line stage to amps. Confession time: For several years, I picked cables based on component-specific interaction, thinking I was fine-tuning my system -- one brand of interconnect for this, another brand for that. Great performance was my goal, but looking back, I suspect some of this cable mixing was really an excuse for not having enough money to do the entire stereo with uniformly decent wires. Bright highs, squishy bass, too warm, too cool -- my system kept changing and my coincidental cable combination never did reach the Goldilocks state of "just right."
Nonetheless, for this review, I broke that rule. The technologies at play in the Anchorwave and Tunnelbridge were sufficiently different to warrant an accounting between them, but taking an additive route eventually got me to a loom-versus-loom comparison. I gave them each roughly three weeks of burn-in before listening critically, which happened over a period of four months. That allowed plenty of time for any residual changes to occur. Art on the wire -- listening to music
first listened to the Anchorwave speaker cables in my otherwise Shunyata-cabled system. The impressive low-frequency weight that I heard during break-in held true across all contexts. With the hybrid Lamm amps connected, the Wilson Sashas lapped up current like cream through those 9-gauge Litz bundles as their woofers purred with weight and tonal depth. Bass through the Lamm M1.2s was the best I’d heard from their pairing with the Sashas: deep, hefty, tonally informed and well controlled. I’ve always heard tonally rich, well-articulated lows from the Atma-Sphere MA-1 Mk 3.1, yet the Anchorwave speaker cables bumped that up a notch to help them deliver a touch bit more grunt and heft than I’d previously experienced from these OTL amps on the Wilson speakers. While the Atma-Sphere amps did not turn into solid-state behemoths, the improvement was welcome. Music through the Anchorwaves exhibited a tonal balance just slightly south of neutral, glancing toward the dark and away from the bright with a tiny pinch of warmth -- not wholly uncolored, just the sort of unobjectionable perception you might expect from a system with numerous tubed components. Soundstage width extended nicely beyond speaker boundaries when called for. I heard the faintest whisper of grain in the upper midrange on the likes of solo trumpets or female vocals. Whether this was a cable artifact or revealed from a source component I could not say; it failed to draw attention unless I went looking for it. Performers and instruments were presented with a solidity that left no doubt about their place within the soundfield. Harmonics and overtones were generally excellent, particularly so in the mid to lower registers. Nicely extended highs gave no sense of brittleness or etch. The transient softness I heard during burn-in resolved to firm attack, though maybe the teeniest bit of rounding remained. I say "maybe" because there are times when I wonder whether contextual factors such as humidity or room temperature or what I ate for lunch have a bearing on such "small" observations. One thing I knew, the more I listened to familiar recordings the more I enjoyed having the Anchorwaves in the system. If a system change brings new discoveries rather than obscuring old ones, it is always a good sign. On Norah Jones’ "Humble Me" (Feels Like Home CD [Blue Note Records JP 5005]), the Anchorwaves told me the harmonics of an air-across-reeds-or-valves instrument belonged to the deeper sonority of a pump organ rather than an accordion. Turns out, I could have looked at the confirming liner notes, but the recognition from listening was much more fun. While the Anchorwaves were a solid performer that I could imagine working well in a variety of systems, adding the Tunnelbridge system proved to be a game-changer. That’s a way of saying its impact was far more significant than the splash it made on first listening. Time for an analogy, one that like the Tunnelbridge itself, relates to electromagnetism: The imprint of the magnetized particles of one section of an audio master tape onto the tape that lies next to it is called print-through. On a record made from such a tape, we can hear the result of this magnetic bleed-through as an echo of the music that is about to be played, a faint message from the future. Apart from hearing this pre-echo at the lead-in or during very quiet passages, I am not consciously aware of the pre-echo that occurs across the entire record. The clarity I heard from music through the Tunnelbridge system was akin to the wholesale removal of the print-through effect. Distortion I did not realize I was hearing was substantially reduced or completely gone. There was no sonic shock and awe; lowering the electromagnetic veil made blatant no single attribute. Instead, it took me several weeks of serious listening to appreciate the new clear character I heard from my system with these cables in place. Paired with the Audio Research Reference 5 SE, the Lamm M1.2 amps laid out a truly multidimensional soundstage when I played Kraftwerk’s Electric Café LP [EMI EMD 1001]. The area around and between my speakers was filled with globs of liquid tonality splashing about like musical paintballs. I already knew the phase tricks this record plays to send sounds wide of the speakers. What was new and very delightful was the same trick in the fore-aft plane accompanied by varying height. It was like wearing 3D goggles and having a sword or a cow’s nose or whatever come toward me -- except the goggles were on my ears. Not only was the soundstage dimensional, I had the sense that each electronic note occurred in its own 3D space, each had its own subtle dynamic shading, each with its own sense of tonal texture. My listening notes described music with tactile adjectives: "solid," "rough," "porous," "sandy," "luminous," etc. Unlike what I heard during break-in, transients now were quick and tight. On "Telephone Call," Karl Bartos' voice came from a dimensional yet disembodied head floating in space, yet I heard how he formed words with his throat and lips. Certain tones had reverb attached while others were cut off with a razor in mid-decay, exhibiting the kind of control only possible from electronics. I have listened to this LP for almost 25 years and heard hints of these effects, but nothing prepared me for the sonic carnival I experienced through the LessLoss loom. When I swapped in the Atma-Sphere MA-1 Mk 3.1 amps with MP-1 Mk 3.1 preamp, their transformer-less clarity was immediate, their superb quickness undiminished and it was a treat to find their lithe midrange muscularity and sumptuous tonal depth better than I remembered. Backup vocals on Steely Dan's Aja [Cisco Records CLP-1006] were rendered with clarity, some with a newfound touch of sweetness. I sensed performers fleshed out with body and movement. Steve Gadd’s work on the hi-hat was exquisite, as I easily heard the tonal and dynamic difference between his touches on the cymbal’s bell and its edge. Wherever I cast my ears, they reveled in fine-spun detail. As sax and guitar arpeggios came to a close, time seemed to slow as notes cast off smaller and smaller dynamic slices of themselves, the near-silent final drop of mid-note tonality pixelating into black air.
In 1979, aided by new technology from Soundstream, Jack Renner and Robert Woods captured the natural acoustics of Cleveland’s Masonic Auditorium, where they recorded Loren Maazel conducting the Cleveland Symphony in Tchaikovsky’s 4th [Telarc 10047]. From microphone through to cutting head, the entire chain was transformer-less. At the time, Harry Pearson hailed this and other early digital recordings from Telarc as "the best sounding recordings from a major label since the Golden Age of Mercury and RCA some 40 years ago." Across the years, I have used the Telarc Tchaikovsky as a show-off record. With its diverse instrumentation, broad palette of dynamics and tempo, and the most feared piccolo solo ever written (21 notes in about three seconds), it has also been a constant for review work. A back-cover photo of the entire orchestra taken during recording made it easy to hear and visually confirm the positioning of each instrument or section and how their sounds projected relative to just three microphones. The orchestra sat well ahead of the back wall, with a lonely bass drum halfway between the two. When I connected an all-Audio Research system with the LessLoss cables, the hall’s acoustic envelope was as close to perfection as I’ve heard from this record. With the orchestral depth clearly laid out before me, my ears could roam easily across contributions from sections and soloists, and then pull back to the whole -- just as I find myself doing in the concert hall. Closer in, the interior bowing action and positional layering of violas and cellos was obvious, even when violins were dominant. In my mind’s ear, I sensed rows of musicians clearly laid out one behind the other. The psycho-acoustic sense of presence coupled with musical vibrancy and performance virtuosity delivered the kind of concert-hall experience that makes all the equipment fuss and bother worthwhile. The oboe at the start of side two evinced proper tonalities and clear articulation, while its distance to the microphones explained why I didn’t hear the structured bite of its reed on initial attack. I heard a faint tonal bloom, a little expanding ball of harmonics that started at a triangle in the back of the orchestra. The crisp leading edge of the trumpet’s attack coursed over the top of the orchestra cutting through the air to the microphones. With the LessLoss cables in place it was easy to hear subtle overtones coming off the fundamental when multiple string sections played pizzicato en masse at the start of the third movement. There was little wall of reverberation as sounds rose in shimmering waves directly above the musicians. Initially I heard a faint hint of silvery frosting on higher frequencies from violins and brass. I did not hear notes pushed forward; it was more like catching a sparkle out of the corner of my eye. Once I reconnected the Anchorwaves to the Reference 250 amps’ 8-ohm taps (from 4-ohm) the frosting evaporated. The LessLoss cables made the difference obvious. With no further distraction from equipment, I put down pen and notepad to revel once again in this vibrant symphony. Here was what it’s all about -- when the music made the stereo go away. Keeping the LessLoss loom as a constant, I rotated though multiple amps, preamps, and different genres of music. The character of each piece of gear and the synergy of different combinations was obvious. The sound I heard was direct and open and the loom did nothing to hide peaky highs, muddled lows or otherwise mediocre recordings. If you are looking for tone controls or compensation for an aggressive-sounding component, these may not be your cables. Other than a wee touch of warmth and grain from the Anchorwaves (or, again, the equipment they connected), what I did not hear was any sonic aberration or common coloration that traveled with the change of equipment. I could not help but wonder about the possibility for further improvement if LessLoss brought Tunnelbridge technology to speaker cables. Regardless of the gear and relative to the ability of each component, the LessLoss cables delivered music with righteous timbre, deep bass, gobs of sonic detail, and a soundstage with realistic layering and image dimensionality. I could talk about frequency balance, speed, dynamics or other characteristics from the grab bag of audiophile words, but in this case, I would be describing specific components instead of cables. Isn’t that the way cables should be? A brief comparison
hunyata Research’s Aeros Stratos-IC interconnects ($5000 per meter pair) and Stratos-SP speaker cables ($6000 per eight-foot pair) served as a comparison loom for this review. These cables came from the middle tier of Shunyata’s previous reference lineup. They used the company’s patented, hand-braided Helix geometry of multiple cryogenically treated pure-copper conductors braided in a counter-rotating pattern that aimed to minimize overall cable reactance, resistance and impedance. I had them in my system for several years and knew them well. It took well over an hour to recable and redress the entire system, which eliminated the possibility for any quickie A/B comparison. Between the Shunyata and LessLoss looms, I heard a collection of small differences that taken together led me to conclude the LessLoss were preserving a level of musical nuance not heard from the Stratos. Lower bass frequencies were the one exception: here the Anchorwaves were markedly deeper with more punch and weight. Listening again to the Telarc Tchaikovsky record, I found the Stratos not quite as resolving and without the same sense of acoustic realism. Not expecting cables to do what the LessLoss did, I was surprised at the overall increase in detail. As for a reduction in distortion, it’s as Joni says: You don’t know what you got till it’s gone. Overall, the LessLoss presentation was more palpable and dimensional, with better separation of instruments and an overall heightened sense of "you are there" in the performance space. I heard a slightly clearer, cleaner top end with more musical detail. There was little night-to-day drama, but the sum of the differences added up to a more realistic musical picture. There really was less loss with LessLoss. In contrast, leading edges were a wee bit rounded through the Stratos with slightly softer attack articulation, particularly on triangles, cellos, double basses and trombones. The Stratos offered a wider soundstage, but not by much. The Anchorwave speaker cables noticeably improved lower-frequency weight and depth, though music from both looms evinced a rich and realistic tonality. Conclusions
he Tunnelbridge interconnect system brings new technology to the design and construction of audio interconnects. Could the concepts behind the design be a pin to pop the cable-coloration bubble? If it makes sense to imagine the elimination of cable variables from the menu of sonic choices that confront the modern audiophile, LessLoss has laid a path to that end. I was not in a position to assess if the Tunnelbridge cables worked electrically as described, but what I heard from a variety of components was entirely consistent with the LessLoss goal of reducing distortion caused by electromagnetic forces and current flow. The Tunnelbridge power supply and power cables brought more componentry to the audio rack along with an attendant need for careful dressing, but the fact that AC powered these interconnects proved of zero concern. The Anchorwave speaker cables nicely complemented the Tunnelbridge, and the combination gave me many a night of delightful rediscovery and new enjoyment of my music collection. What I heard through the LessLoss cables was more
component and less wire, more music and less cable-induced noise. The positive effect of
the Tunnelbridge system was clearly audible. It offered new insights about the ability of
my system to deliver musical enjoyment, and in so doing, it redefined my expectations for
audio signal cables. What you might hear through these cables will depend on the abilities
of the components you have, but I am confident that the LessLoss loom will bring your
system a step closer to its capacity for musical truth.
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As a theoretician with a
certain Kantian flair for critique, and as a designer with many hours of computer modeling
under his belt, Motek demonstrated a facility for boiling down complex problems to a
simple question: what conditions need to apply for an interconnect to avoid distortion and
audio signal loss? Acknowledging that well-understood electrical parameters such as
inductance and capacitance are elements of cable design, Motek's own studies suggested
their impact is not actually that significant over the relatively short distances covered
by home stereo cables. Differences in electrical properties alone were insufficient to
explain why cables affect sound the way they do. After all, cables that exhibited
near-identical electrical specifications often produced quite different sonic results.
Nowadays, after listening
in-house to dozens of cables, after multiple system upgrades and cable reviews, I’m
an ardent "loomer." Trying to assess the sonic performance of a single cable by
inserting it into an existing system strikes me as being about as cogent as assessing
Bridgestone Blizzak snow tires by mounting one on a car otherwise shod with Pirelli
Sottozeroes. Sure, something will be different, but not in a usefully describable way to
anyone interested in Blizzaks. I am convinced only a full loom of signal cables or power
cords, or ideally both from a single manufacturer, offers a reasonable evaluation context.
The LessLoss cables
delivered the riffs and rhythms of this classic album with a directness and clarity that
gave me both a new respect for the exacting production values behind Aja and
offered insights into the abilities of the components they connected. It sure is sweet
when a new product flatters my existing system rather than revealing previously unheard
flaws. I’m happy to call that progress.
