Saving up

April 28, 2017
 by Paul McGowan

The best sounding cables I have heard were a bare set of wires. Hardly practical in the real world, cables without shielding and insulation sound better than those with them.

We insulate cables so their conductors don’t electrically touch each other. We shield them with tin foil or woven metal to protect them from noise.

None of these techniques of isolation and noise reduction improve sound quality. Air is the best insulator and a noise free environment what we hope for if we want to avoid shielding. Unfortunately, dangling conductors in the air is as impractical as hoping for a noise free environment. Insulation and shielding are necessary evils.

The problem with insulators is energy storage. When a signal is passed along the conductor they cover, small portions of the signal are stored then released in the insulation. This effect can be measured and enumerated using what’s known as the Dielectric Constant. If we’re building a capacitor we want that number high. If it’s a cable, the lower the number the better.

Of the readily available insulation materials, Teflon has one of the lowest dielectric constants—far lower than standard insulation. But Teflon’s expensive and hard to work with, which is why it’s used sparingly.

In our ongoing discussion of break-in, I suspect it is this dielectric constant that changes with signal.

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45 comments on “Saving up”

  1. Paul,

    Unfortunately, I have to disagree.
    The dielectric constant is, as the word implies, constant and thereby does not change.
    It is the relative permittivity which changes with frequency.
    Nevertheless the magnitude is negligible in the audio band.
    The dissipation factor of PTFE for instance is 0.0002 @ 1kHz.

    One more time, I’d to run through 5 captchas until I could log in. Why?

    Regards

    1. The constant doesn’t change but the measurements of it do.

      There’s often confusion about insulators and dielectrics. But it is the dielectric constant that is used as a measurement scale.

      • Insulators are material which are resistant to electric charge flow, while dielectrics are also insulating materials with special property of polarization.

      • Insulators have a low dielectric constant, while dielectrics have relatively high dielectric constant

      • Insulators are used to prevent charge flow while dielectrics are used to improve the charge storage capacity of capacitors.

      So you can see, we want our insulator to have a very low dielectric constant because we’re not wanting to build a capacitor in our cable – but despite our best efforts, our insulating material will always exhibit some of these characteristics.

      You’re right that officially these parameters should impact only higher frequencies, in the megaHertz regions and not the audio – but different insulating materials sound different – thus implying there’s more going on than meets the eye/ear.

      1. ” Insulators are material which are resistant to electric charge flow, while dielectrics are also insulating materials with special property of polarization.”

        When an insulator is placed in an electric field, the electrons will tend to migrate (spend more time) near the positively charged plate which attracts them and be repelled by the negatively charged plate. Their mobility depends on factors that are related to how tightly they are bound to their positively charged nucleii. This can effect their suitability as dielectrics for capacitors. Once the field becomes as strong as or stronger than the ionization potential of the bond, the electrons escape the nucleii and the capacitor is destroyed. We now have a new class of capacitors known as “supercapacitors” whose capacitance is much higher than other types for the same size.

        https://www.google.com/?gws_rd=ssl#q=supercapacitor&spf=403

        In a simple electronic timer I recently specified, the usual battery backup was replaced by a supercapacitor said to have enough charge to maintain memory for 100 hours.

  2. The only cables I ever made myself were a pair of solid silver, pretty much to Paul’s specification. 2mm single core silver, 4mm internal diameter teflon tubing, some heat shrink and bare wire connected. Components purchased on Amazon for $250 and took an hour to put together. Sounded no better or worse, but teflon tubing that thick is fairly rigid and does not easily go round corners.

    Jazznut asked about USA audio in the UK. He asked if “folks” in the UK limit themselves to local UK brands. I can assure you that is definitely not the case.

    Probably the best selling high-end/audiophile brand in the UK is Naim. You have numerous other well-known brands with global reputations – Quad/Linn/SME/PMC, loads of them. Quad, for example, is one of several UK brands both owned by Chinese (IAG) and manufactured in China, but you can send any product going back to ESL57’s or Quad II’s to their Huntingdon HQ and get then serviced like new. You have old and new. IAG/Quad/Luxman etc are 10 miles from dCS. Naim is owned by a French company that also owns Focal. A lot of UK audio is designed and distributed but neither made, sometimes not owned, in the UK.

    The UK market is no different from Germany, France, Holland, Belgium and Italy, all of which have significant audio industries. Munich in a few weeks is the largest audio show in the world.

    So the European audio market is congested, but most US brands are represented in the UK. PSA’s distributor represents 3 brands, all from USA. I don’t think there is any national loyalty in the UK but, like anywhere, there is probably a lot of brand loyalty, which is what I think keeps companies like Linn and Naim going.

    http://hifilounge.co.uk/brands-at-hifilounge
    https://www.highendheadphones.co.uk/index.php?route=product/manufacturer
    To give you an idea, this link is to a very enterprising chap who set up an audio dealership about 10 years ago, with a separate specialist headphone business. It has been very successful. In the countryside, but well located to visit and very nice premises. Naim always paid the rent. He has a very close relationship with PMC/Bryston, who are 3 miles away. (PMC are a major consumer brand in the UK.) After that, he tells me he just chooses brands he likes and you can see they come from all over the world. He told me he particularly likes McIntosh.
    http://www.hifi-bauernhof.de/produkte.htm
    On the other hand, this excellent German dealer (amazing facilities) has more UK brands than most UK dealers (they are big on E.A.R.), and precious little from the USA.

    Obviously quite a lot has to do with the ability to service and ship items, cheap and easy within Europe, less so with USA. However, I think quite a lot of USA high-end audio is perceived as relatively expensive.

  3. I about to order Stager Silver solids cables; reasonable price, without shielding… Also tried Anti-cables, not bad, but hardly practible in my situation because of its springy character.

  4. Paul. Thanks for suggesting a mechanism which might explain burn-in effects, I appreciate it. On general principles it seems unlikely, and I have not found any reference to it in a few web searches, but I am not a materials scientist and so cannot reject it out of hand. I suspect, however, that if it were a marked effect then there would be such references. Since I am a doubter about the benefit of special lower impedance speaker cables in most domestic situations I am a double doubter about any slight changes in that caused by burn-in (if they actually occur) being audible.

    However one point interests me. The articles discussing the effects of speaker wire impedance seem to feel it is negligible if less than 1% (some claim 5%) of the speaker impedance. This may be true for the general populace, but audiophiles do listen to their systems with much greater critical attention. Can they detect changes of a fraction of 1% in the audible frequency spectrum balance? We are not talking about ‘night and day’ changes here, but small ones which might still be reliably detectable. I have never noticed them myself, but then I class myself as an audiophilistine.

  5. Could someone explain why an interconnect or speaker cable that has not been used for some time, sounds different (wrong) compared to one that has been used regularly even though they are exactly the same?. This anyone can check.

    I have verified that cables that are not being used take some time (fortunately not much) to recover the sound characteristics similar to those that are constantly used. I think this wait is more friendly than the expensive AQ wires with batteries.

  6. Hasn’t the cable subject been talked about to death? Or is it like religion where one has to be re-indoctrinated every week for fear of individuals thinking for themselves and the preachers having to get real jobs?

    1. There are always new people coming onto the scene and since no one has ever answered these questions properly I think it’s healthy to keep bringing them up.

      And yes, they have been talked through to death, but until there’s an answer that we can all live with, I am afraid they will continue to be talked about. It’s the only way I know of having a chance at learning something. Even a glimmer of knowledge would be helpful.

      We hear and experience things our science cannot explain. That’s always frustrating to us engineering types.

      1. “There are always new people coming onto the scene and since no one has ever answered these questions properly I think it’s healthy to keep bringing them up.”

        Yes but there’s still that pesky old Telegrapher’s Equation that just won’t go away. It’s called “a distributed parameter filter network” so cables DO matter. Have you tried medium voltage cable such as those rated for 15 KV. I’ve been studying them a lot lately. They have a copper inner core, insulation, a grounded copper shield, and an outer jacket. The question is, which insulation sounds better, EPR or XPLE? Utilities typically use 2/0 for many buildings but at Bell Labs 500 MCM and 750 MCM were used exclusively. You will of course need four just like the vacuum jacketed cables I described below. Well actually they are vacuum jacketed pipes but they can be used as cables. Two good suppliers are Okonite and Perelli.

      2. dont worry . we call them
        hallucinations, and they happen to the best of the rest of you . ha ha. jk , me too. ( does the iphone se breathe ?)

    2. I, for one, propose a monthly cable discussion where we can revisit and learn about this important and fascinating topic that intimately affects the music we hear. Open to all cable lovers.

      BTW, vsopking, you’ll like the sound of the Stager cables.Great bang for your buck.

      1. ;-))

        although I’m not so sensible to multiple cable or flac/aif sound difference discussions, because I see more ignorance than experience in this field and see some missionary work useful, I occasionally also suffer from such initiatives i.e. when I nearly monthly read hints to how bad the dynamic range of vinyl reproduction is and that people who listen to vinyl probably do this because they a) either like reduced dynamics or b) compare vinyl with inferior masterings on CD (which in my eyes is a misuse of a single mostly irrelevant true aspect (a) respectively an optional fault while comparing (b)).

        No I don’t want to start the monthly vinyl discussion 😉 It’s just to point out, probably everyone has his sensibility to missionary work, either driven by ignorance, different opinion/experience or better knowledge. I don’t claim the latter for myself (often ;-).

  7. How does a cable carrying the signal from a low output moving coil cartridge (0.2-0.5 mv) ever break in? -And yes, I still listen to these vestiges of the analog age. I’m thinking that there may be a place for the Audioquest dbs cables in this application.

    1. That’s a very good point and asks whether “break in” is voltage-dependent, if it is needed at all. My m/c tonearm cable is the most expensive cable in my system. It was an option on an Origin Live tonearm, but Origin Live are one of several companies to offer a rewire service and rewire kits to the otherwise excellent Rega tonearms.

  8. Since we are in the land of audiophile OZ, I’ll have a little fun today. Now for signal cables I’m sure Paul would agree that using digital signals sent through fiber optics (I’m talking the real thing, not trash like Toslink) would be just fine since streaming audio is sent through exactly the same kind of method and there’s nothing wrong with it. But then there’s those pesky speaker cables. So how do you get speaker cables where the conductors are not just insulated by air but by a vacuum? Can it be done? YES with products that have been around for a long time. Is it crazy and expensive? We’re talking audiophile here where anything goes. I just love using products for new applications no one ever dreamed they’d be used for. The product is called “Semiflex” and it is made by a company called Vacuum Barrier Corporation. Its intended use is to deliver liquid nitrogen from one place to another without it boiling away. Remember it must stay hundreds of degrees below zero so it has to be transported in a vacuum. You’ll need four, two for each channel. Download the PDF to see how it is constructed. (I used this product nearly 40 years ago for its intended purpose so it’s in my bag of tricks.)
    http://www.vacuumbarrier.com/piping/semiflex.html
    You’ll probably use one from the “A” series where the inner pipe is oxygen free copper. The inner and outer pipes are separated by a helical nylon ribbon that has almost no thermal or electrical conductivity. The system of choice is continuously evacuated. The product I used had two pumps, a mechanical pump that got the vacuum to 50 TORR and then a molecular pump that got the vacuum down to 1 TORR or less. You won’t need a phase separator because there is no gas at all to be separated from the liquid as in the case of cryogenic nitrogen. You might also want to consider their “Cobraflex” product.

    1. — electrons move in the range of a few feet or inches, per second —

      — the sound ( current) travels in a magnetic wave
      in the range of light speed outside the conductor, in the range of nanometers to miles —

      — sounding different doesnt necessarily mean better —
      ….discuss amongst yourselves .

      1. Individual electron movement is not what transmits electrical energy and signal, it is bulk electron flow which is 1/2c-1/3c for the EM wave in normal wire construction .

        Your last statement is a description of the audiophile effect. All human senses at all levels of cognition ignore constant stimulus and accentuate changes. When you change something in your system, it will sound different and expenditure predisposes one to preferring the new. Given the right timing of human break-in (which is most break-in) this can go in a circle forever.

          1. Actually, you can. Think of it as quadrillions of relay races which each have 100,000,000 member teams. The individual electrons only move a few meters a second, but the runners are collectively are covering 100,000km/s.

    2. Wow! Anyone willing to try these in a listening A/B test? I don’t think it could be blind because of the pumping noise.

      Soundmind, where should the pump be placed?

    3. Apropos Crazy audiophile OZ…
      Imagine a cable that’s molecular treated, so amongst other effects atomic corn boundaries are quasi eliminated (not cryogenic treatment, much more effective). Imagine whole components treated like that. I’m listening to it. At least as cabling it’s commercially offered.
      No way to listen without anymore if one heard it, you can’t imagine which limitations suddenly are eliminated. It’s just expensive as you can fancy which equipment must be used to achieve that.

  9. Very happy with my AntiCables speaker cables, except they are not to be tripped over…

    Tempo electric has a recipe for speaker cables that uses an oversized insulator which surrounds a solid silver wire inside. Since it is oversized, it only touches the silver in some places. I would be happy assembling a set if I had actual feedback from actual users… hello?

    1. I have a very long post being moderated, but the first paragraph answers your question:

      The only cables I ever made myself were a pair of solid silver, pretty much to Paul’s specification. 2mm single core silver, 4mm internal diameter teflon tubing, some heat shrink and bare wire connected. Components purchased on Amazon for $250 and took an hour to put together. Sounded no better or worse, but teflon tubing that thick is fairly rigid and does not easily go round corners.

      I don’t use then as my amp does not take bare wires easily and I splurged out on posh cables second had at 25% of retail. The very low resale prices of many cables suggests there is a lot of chopping and changing going on, given the lack of reason behind what’s good or not, and hence a surplus of available product.

  10. The closest thing to “insulated” bare wire I found? Litz that is left alone… to look like crap in its threaded server. You’ll need a solder pot to tin the ends. Looks like junk. Yet, sounds as neutral as practicality will allow for. I have litz interconnects floating inside cotton tubes. Neutral. I also have some shielded litz interconnects …. smoother than reality. Litz eliminates an inherent electronic buzz that typical stranded cables bring with them. On first hearing what you listen to may sound dull. But, its that electronic buzz that now has been eliminated. Cymbals sound real. That was my first impression.

    I shake my head how what I visually see (plain looking)… when its compared to what I hear. Its like having an informed, blunt, and brutally honest friend. It lets you know immeditately where your system’s deficiencies are, and also when something is truly beneficial.

    The next best thing would be solid core cables having no insulation except for the thin sprayed on covering like found in the Anti-cable. Unlike solid core, Litz has each fine strand thinly coated. A fine coating that insulates each strand from the other. That’s the reason you will need a solder pot to tin the ends.

    It might be reasoned that Audio Research uses litz in its constrcution, and with its cables… with good reason. But, AR found the need to wrap them in plastics to make them look presentable to the fickle audiophile. Bare litz is the closest the neutral I can imagine. That is what I use for my speakers. My interconnect manufacturer, semi compromised, and used cotton tubing for appearance sake… I understand. As neutral as practicality in a fickle market will allow for.

  11. So if dielectric is a big deal and separate wires are the best thing, then why don’t we do separate wires instead of deliberately laying the wires next to each other?

    1. A J Vandenhul does something like this in one of his speaker cables : two very large separate cables that you twist together to achieve the desired capacitance. Some people think it sounds good, but I certainly have heard better in my setup. We’re getting knee deep in snake oil here, but I couldn’t resist a comment.

        1. Sorry Russ, but I really don’t know. I’ve used them twisted together (3 twists per meter) and completely separated. I couldn’t tell any difference.
          Better ask an engineer. I think there are some around here.
          Cheers,
          John

          1. I’ve never heard any difference in speaker cables. I do hear subtle differences in interconnects, but not speaker cables. I’m good with 14 gauge zip cord from Parts-Express. Given that I have 8 runs of 25 feet each for my multi-amplified loudspeakers, I couldn’t afford anything else anyway.

        2. Mostly, but you would then have created a fine loop antenna. RF interference on the output can reputedly upset some amps. I am too old to do the maths about it any more.

  12. Dielectric constant can shift frequency response slightly, that is not the problem.

    The sound of insulators and capacitor dielectrics is from dielectric absorbtion and dissipation factor. This is non-linear energy dissipation, absorbtion and emission because of electrostatic domain interactions. Any good impedance bridge can also measure one of both of these wire parameters.

  13. Yooze guyz got it all wrong. The reason it breaks in is cause when you get it, it’s all coiled up. The electrons expect to go round and round. When you unroll it, it takes time for the electrons to learn how to go straight. Once they get it, it’s broken in. See how simple that wuz.

    1. Well, if you disturb the cable after it’s broken in, the electrons get mad and confused. Then you have to retrain them. Moral of story: don’t screw with contented cables.

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