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Positive Feedback ISSUE 30
march/april 2007


We sent out the same 20 questions to 50 manufacturers, the following are their responses. The intent of the survey is to address basic questions as to design along with any questions raging on various sites, while minimizing potential chest-thumping and friendly, or unfriendly, bashing of others....

Click here to read the other interviews in the series.


Elliot Davis of Ecosse
by PFO

PFO Why do cables make a difference? Interconnects, speaker, and AC cords?

Elliot Davis Cables, being the longest part of a system, act as efficient antennas, picking up or radiating electrical noise. A cable's ability to minimize unwanted noise and to accurately transfer the frequencies inherent in the audio spectrum—20Hz-20Khz+—impact on the performance of your system.

There is no such thing as the perfect cable-what we at Ecosse strive for is to improve the options for the end-user—to maximize the potential of their system without having to spend vast fortunes in the process. The choices of conductor and dielectric are vital. Different metals and the structure of the conductor itself play a vital part in the speed and accuracy of the sound.

The choice of dielectric (insulation) is also vital, since a bad choice can increase the capacitance and induction between the +/- wiring which affects the top and bottom frequencies. Cables also need good insulation from the effects of RFI, EMI, and ESI (electrostatic interference) that inhabit the world around us as well as influences between the cables wires themselves. The choice of design of connectors is also important, as it provides the link to the next stage in the audio chain. To sum up, the choice of conductor, dielectric(s), insulation and termination pretty much define why cables make a difference.

PFO What about metals ...copper versus silver versus gold versus what? What about blends?

ED No metal is absolutely pure, and contamination, as well as the crystalline structure of the metal, can have an often-dramatic effect on signal quality. Impurities within the conductor, including oxygen, silver, iron, sulphur, antimony, aluminum and arsenic, coalesce at the grain surface. This creates much higher impedance to the electron flow by essentially forcing the electrons to have to 'jump' those poorly conducting boundaries where grains touch. Thus, all metals ultimately act as a barrier to the delicate audio signal, so it's all about reducing this barrier to let the electrons flow.

As the current flows from one molecule to the next in a wire it conforms that the best metals to use for audio cables should only have one electron in the outer electron orbit. Luckily this is true for silver and copper (and gold also, but gold is crazy-expensive and does not justify itself in price-versus performance audio–wise). However, silver has one further "orbit" than copper, which makes the distance from the nucleus even further, so making the flow of electrons easier and therefore quicker and more precise. In fact silver has a 10% gain in conductance compared to copper, this, as we often do, a copper wire plated with silver will have less signal loss especially at longer lengths.

Blends are a bad idea, since mixing materials will affect the overall sound.

NB: Bringing Monocrystal™ (and recently SuperMonocrystal™) pure copper and silver within the reach of most audiophiles is Ecosse's lasting legacy to the audio industry. For the first time (in decades) sensible/real world prices can obtain this sonically vastly superior conductor material: material which ensures, uniquely, an almost complete lack of 'grain-boundaries' in the signal transmission direction - impurities which would as we have noted, normally impede the delicate audio signals and result in attenuation and distortion

PFO What about dielectrics... Teflon versus what?

ED A perfect dielectric will store zero energy and therefore, not take away any signal from the conductor. The closest to a perfect dielectric is air with a dielectric value of one, but it is not practical to use air as a dielectric as the entire assembly would have to be hermetically sealed (sic).

Dielectric materials absorb energy, a phenomenon called dielectric absorption. Dielectric absorption can degrade the signal so it's important to use the best dielectric insulation for the task as the energy absorbed by the dielectric is released back into the interconnect slightly delayed in time—an undesirable condition.

At Ecosse cables we use either polyethylene or Teflon™ (PTFE- polytetrafluoride epoxy) dielectric as these insulators exhibit superior mechanical properties (such as isolation to vibration) to maximise the signal and its transmission velocity.

In some of our cables these two dielectrics are combined within the cable's topology. Air-Foaming reduces the dielectric constant (the dielectric constant (D.C.) of the insulation material influences the ability of the cable to deliver rhythmic, fast and uniform sound) and the dielectric loss by introducing air, thereby stabilizing the frequency characteristics of the cable.

Thus: Dialectric Material: Best AIR, Worst PVC; Most Practical: Foamed PE or Teflon™

PFO What about no dielectric?

ED As mentioned above, air is better than PE/Teflon/etc. A perfect dielectric will store no electrical energy and therefore won't remove any signal from the conductor. Thus, the closest to a perfect dielectric is air. However it is impracticable, so only used in some cabling as an additional method of insulation—e.g. air gaps in polyethylene/Teflon™ e.g. our 'Legend' Monocrystal™ Interconnect has a tertiary, unique, patented PTFE (polytetrafluoride epoxy) ultra-low D.C. air-space dielectric between conductors.

PFO What about measurements... what do they tell us? what do they not tell us?

ED Listening tests are far more important than simply quoting measurements, however—and has been recently shown in an article in New Scientist Magazine—people are more easily 'converted' to new products when there is visible/written proof that they do work. However making measurements is not always that easy, nor do they actually mean much; for example I prefer the sound of an amp with 65dB S/N ratio and 20-20,000Hz +/-3dB frequency response to some "mega" impressively quoted one with 120dB S/N ratio and 0.1-250,000Hz +/-1dB vital statistics! Some things are just not so easily understood other than just by 'listening' to the music the way the artist who performed it intended it to be heard.

PFO What about connectors... how important?

ED The terminations at the ends of cables are part of the transmission path and therefore vital to it. However connectors are often the least thought of part of a cable. As it will be connecting to another connector (socket) there needs to be optimum contact between the two without inducing capacitor or resistor characteristics.

A soft metal such as gold or silver is ideal for the connectors as this is pliable to an extent. Similarly the design, such as the Ecosse Z/X OFC and Monocrystal™ banana speaker plug is designed to cling to the socket. A non-pliable or hard plug is not a good contact. Nor is the use of brass plugs that are gold plated, since there are two metals which inherit other problems as discussed above. Blatant …er, plug: Ecosse are the only company in the world offering non-compressing copper RCA plugs on our premier/premier+ analogue, digital and video interconnects, and grain-free Monocrystal™ plugs (RCA and XLR) in our more expensive audiophile/reference grade cables.

Finally, some believe that the ring or –ve connection should be of the same contact size as the +ve, and so make plugs with no ring but just a point contact. We believe the –ve should be a complete ring as in the traditional concept of RCA plugs. We also believe in double insulating the outer ring (i.e. have two rings) so that the outer ring (connected only at one end of the cable to the –ve and acting as a double insulation wire) acts as a faraday cage.

NB terminations become oxidized over time and the connection can become 'bad' to the point where clearly audible distortion occurs. To reduce this concern Ecosse uses gold or silver plating on our plug terminations. Many of our competitors do not take this care and attention in their terminations-they still use tin/leaded solder and run the risk of galvanic corrosion. Use of tin/leaded solder is now illegal in the EU.

PFO Why this geometry... ribbon, twisted, braded, spiraled...

ED In an ideal world the negative and positive wires should be kept well apart. If they do have to be placed next to each other then to minimize magnetic and electrical radiation between them then they should be at 90% to each other. Hence 'twisted' wires are ideal, and spiraled geometry is an added bonus. Wires also generate vibration since there is electrical alternating current flowing, and therefore some kind of damping factor needs to be considered as well; such as cotton or silicone.

There is an argument for and against the skin effect—whereby higher frequencies traverse on the outside of cabling- requiring a 'solid-core' as opposed to multi-stranded cable for the treble of bi-wired loudspeaker cable. This argument can be challenged in that some insist it only affects frequencies well above the audible level. However, whether we are affected by these "super harmonics" is debatable.

PFO What about cryoing? What is going on with this?

ED We believe it makes a difference, thus, Ecosse uses cryogenic treatment. Specifically, for non-ferrous metals (such as Monocrystal™ copper and silver), 'sub zero treatment of the material results in reduced residual stresses in both conductor and dielectric. By slowing down atomic movement, the internal molecular bonding energy is increased which promotes a pure structural balance throughout the mass of the material. The end result being a material with an extremely uniform, refined and dense microstructure with vastly improved properties.

PFO Why shielding? Why not shielding?

ED We live in an invisible sea of electromagnetic energy, caused by the electronics we own, radio stations, the earth's movement through space, even the sun's radiations. EMI, RFI and ESI are on the rise with mobile phones, wireless LAN's, digital radio and digital satellite TV broadcasting, all attacking your mains. Now with the arrival of 3-G phones with their always live radio connections and wireless broadband internet connections, you are looking at a hideous soup of RFI that your mains just loves to transmit into your audio equipment. All these signals, when summed together in your living room, are called EMI/RFI.

Shielding from extraneous influences such as RFI/EMI interference is vital in getting the best signal from one end to another. Another layer of shielding reduces magnetic infiltration. Additional shielding from mains-borne interference using *well selected* mains conditioners is also vital in getting the best signal from one end to another. Some conditioners simply compress the sound and add too much bass.

PFO What about run-in? why is/isn't it important?

ED We believe cables need to be run in for a period of up to several weeks before its chemical properties are optimized. Just like a car needs a period of run-in, cables need the same treatment as the electrons need to get used to being 'excited'.

A cable also needs to physically settle before it is at its best. Therefore it needs to be unmoved for a period before it is able to perform at its best. Flexing it changes its electrical properties.

PFO What about lengths? why are/aren't they important?

ED Basically, to reduce impedance, capacitance and inductance all cables should be as short as possible—though it is imperative that all cables that are being used simultaneously are all the same length!

PFO What is directionality?

ED There is a big debate about directionality in cable. If electrons are excited in a cable they adapt to the motion they are making, and any change to that pattern can affect the sound heard—often a slowing of transients and reduction of higher frequencies. Therefore reversing cables can confuse the electrons. There is an argument that as electrical sound waves are an alternating current the electrons are moving in both directions anyway. So the directionality camp is often laughed at. However, it is quite noticeable that there is a change in sound when one of the two connectors is reversed; e.g.; left loudspeaker or left interconnect cable is reversed. This could be explained by the fact that the wire was extruded in a particular way and so reversing this can change the sound.

PFO How did you get into this?

ED Needed to improve the sound in my recording studio-started to mess around with new cable designs using a technology I was aware of but long defunct-Monocrystal™ (we own the trademark) grain free copper, realized they were working BIG TIME in my recording studio, thought it might be a good idea to make the technology available to others-and at prices they could understand.

PFO What is your fundamental design philosophy/goal?

ED Simplicity (of component and design), producing the closest to the original source.

I think this statement can answer all these: We strive to keep things simple: appropriate high resolution interconnects are designed to be dedicated to their respective interfaces in the audio or video chain. 'Speaker' cables employ high quality 'low-loss' dielectrics in order to facilitate the long runs necessary in modern esoteric hi-fi and multi-room or home cinema systems. Speaker cables are also made available in a variety of sizes, since the size and type can influence the depth, clarity and timbre of sound.

We firmly believe in price-versus-performance and are confident that we have the most impressive across-the-board range of cables throughout the entire cable market. The quality of our cables in terms of conductor material construction and termination at similar price points will not be beaten-that's why we come out tops in most comparative tests against all our rather over-hyped competitors. We came to the market just ten years ago and ALREADY we are the most successful new stand-alone cable company in Europe.

What we do is ensure that all our cables, before they reach the market, have undergone months/sometimes years of extensive research, development, and unbiased audition (against many of our vastly over priced/over rated competitors) until we are certain that two simple requirements are fulfilled: that they perform better than the less expensive model in our range that as far as we can get our hands on them, they outperform our major competitors at similar price points. If a new Ecosse Cable does not meet these two simple criterion they never see the light of day.

PFO Others that you admire?

ED Of all the questions that you posed, this one caused the most 'bother'. Not one to blow our own horn (well not overly so I hope) I'd rather talk about Ecosse Cables (natch) than promote our competitors. Still, cable wise I have a sneaking regard for what Silversmith Audio is doing and also Audio Teckne. Equipment wise I doff my hat to audio-genius Mr. Eduardo de Lima of Audiopax—not a finer amp/speaker/preamp combo on the planet! There I said it—so sue me!

Click here to read the other interviews in the series.