cable dielectric cause of artificial sound


Hi folks, I would like to know what your opinion is about the following issue. About 90% of high-end cable manufacturers use PTFE as dielectric. Many of their cables sound much alike and they have a few of these characteristics in common: clean, relaxed and laid back sound but at the same time very dynamic (though a bit artificially), very quiet ("black background"), very good (also artificially) left/right separation. But I think albeit these traits, they tend to sound "technicolored", "sterile" and unengaging (lacking PRaT also). Some cable manufacturers are using bleached cotton as dielectric. These cables sound different: they have more natural dynamics, a mellower sound, more intimate soundstage, more tonal colors and so on. Are these differences mainly due to the dielectric material used? Why is for so many manufacturers PTFE still the ultimate dielectric for the use in audio cables?

Chris
dazzdax
Tplavas, so the matter is more complex when you regard RFI and EMI as independent factors. Some cable manufacturers are twisting the conductors very tightly (with almost 90 degrees angle). I can imagine this adds an extra measure for rejecting RFI, but the EMI field is quite dense around the conductors, so it also can negatively interfere with sonics. Or is it beneficial to get the EMI that strong around the conductors? If that is the case, maybe the philosophy behind Rick Schultz' Virtual Dynamics cable is right: making a dense electro-magnetic field around the conductors by using magnets.

Chris

Chris
I've always said that shielded cables will perform & sound better, when properly implimented. I just don't know of any commercially made cables that are properly shielded, mostly for the reasons you site above. Sean
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Sean,

Excellent post, but I think you need to be very carefull when addressing the EMI/RFI issue. Some cables that reduce EMI/RFI issues also dull the musical signal. I think it's important to focus on clarity and dynamics when listening for EMI/RFI problems, not just tonality, because there are already too many people who falsely believe (IMO) that because a cable has reduced the treble response in their system, that it has 'only' removed EMI/RFI grunge, and that their sound is now more accurate; when in fact they have indeed given up some musical information.
A useful learning tool is to apply ferrites to analog interconnects to see how much of a change they make in the sound of a system. Once the listener can quantify that level of change in their mind, it makes determining whether other cable designs are actually better at shielding/rejecting RFI, or are just rolled-off.
(I Should state at this point that I AM NOT endorsing the use of ferrites on analog interconnects).
EMI is trickier, in that so many products use materials that reduce EMI to the detriment of their sound. By placing shielding/insulating materials too close to the signal carrying components, they interfere with the EM field, which impacts the resulting sonics of the system. It seems like some manufacturers would like their potential customers to believe that if a little EMI shielding is good, a ton of it must be great, when nothing could be further from the truth in my experience.

You're right, I feel like I could go on ad nauseum, and still not completely describe my ideas on this subject.
But I guess that's why I love this hobby so much, there's always something more to think about.
There are many valid points being made here, but i think some of the data is being misinterpreted. Obviously, what i posted above was just my point of view. Since we are sharing our points of view, why stop there ? : )

I've mentioned before that many manufacturers cling to one type of geometry for their entire product line i.e. their interconnects, speaker cables, power cords, etc... all use the same basic or extremely similar geometry and philosophy. That's where most of the problems come from.

Each electrical interphase ( component to component, AC outlet to component, amp to speaker, etc... ) has different electrical characteristics. They therefore require different design criteria for optimum power transfer / minimal signal loss characteristics. Obviously, this requires knowing how to juggle all of the variables involved and making some personal decisions as to what one thinks are the most important aspects of signal conduction.

In some cases, minimal signal loss is NOT what is most desirable, so that can also be designed into the product via juggling conductor geometry, dielectric absorption, etc... Once again, this requires an intimate knowledge of how things work, both alone and in conjuction with other materials, and personal decisions as to what the primary design goals are.

On top of that and / or outside of that, certain cable geometries / dielectric materials contribute to cable rigidity. Increased cable rigidity increases cable microphony i.e. the cables acting as microphones and introducing random distortions into the signal. This microphonic distortion introduces a random low level haze, increasing the noise floor, reducing micro-dynamics, reducing focus, etc...

Bare in mind that these distortions can be generated physically ( cables laying on top of devices that transfer energy into them ) or acoustically ( high spl's vibrating air-suspended cables, etc ).

How cables deal with vibration / microphony is a complex subject that many "audiophile approved" manufacturers have never studied or looked into. Many EE's don't believe that microphony is a problem in anything but an utterly defective cable, but i'm not of that opinion. I've seen and experienced very measurable microphonic differences in what one would normally consider to be "good" cabling.

Outside of OR on top of that, some cable geometries are more / less resistant to RFI / EMI induced interference. This type of interference is typically found to introduce high frequency smearing aka sibilance, hardness or brightness into the system. Depending on the degree of the interference and how susceptable the gear is to RF induced noise, some of the aforementioned problems can be perceived as increased brilliance, increased detail, extended treble response by the uneducated ear.

On the other hand, someone used to listening to this phenomena, and having the RFI / EMI reduced or removed from the system, may think that the system now sounds soft, dull, dark, muted or lacking in treble response. In all actuality, the system is now more linear with a truer response, it is their perception that is distorted.

Outside of OR on top of that, there's always the impedance related issues that are involved. Depending on the stability of the gear / circuitry involved, the various aspects of performance i.e. amplitude linearity, frequency response, transient response, distortion characteristics, etc... can be effected.

It should also be noted that any / all of these variations can be random at nature depending on the design of the gear and the impedances that they are presented with. Since the impedance that each cable introduces into the system is placed in series with the impedances of the connecting circuitry, different cables of varying impedances can introduce quite a few variables into the same component based system.

These are but three variables that can alter cable sonics. As previously mentioned, unless ALL of the variables are controlled in phenomenally tight fashion, the differences in cabling / system interaction are typically the result of multiple varaibles, not just one.

This is a PHENOMENALLY complex subject, that obviously can't be resolved in a thread like this. As far as i can see, we need to keep learning and sharing if we are to make any progress in this specific area. Sean
>

JD wrote: "I assure you the interconnects your so happy with will be gone from your system for ever"

If I found something that made the image any bigger than these I don't know what I would do. Like I said I want to try Mapleshades "ribbon in a bag" type interconnect. Thanks again.

ET
How 'bout paper, used about 50 years ago
Why not. It's got a dielectric constant of 2 (dry, at normal room temp). I tried it and it didn't make me run out of the room. OTOH, I can't recommend except for very careful and foolproof implementation otherwise one runs the danger of wires shorting...
high purity wire in a vacuum
Snag is, the contacts are still exposed and need cleaning periodically... not to mention the difficulty of the implementation (which you do mention).

At the end of the day, JD's use of gold wire -- despite the cost -- seems like the most practicable solution.

After all, paladium would be text-book ideal -- but at a more than textbook price.
Kapton sounds better than Teflon. Cotton absorbs moisture. How 'bout paper, used about 50 years ago.
my audio junky friends & i have found that dielectrics, teflon included, invariably screw things up.

downside is the availability of cotton-dielectric (the VHAudio wire is a good gauge, but poor quality), and the difficulties of construction / durability of bare wires. cleaning terminals w/ progold is all the confirmation i need of the negative impacts of oxidation.

the ideal strikes me as high purity wire in a vacuum. tough to come by though..
rhyno
Hi ET,

I think what you are experiencing is how most interconnects made actually suppress the signal. In most cables they have the conductors very close together and wound in some fashion. The industry has gone deep into this philosophy deciding certain wire twists or weaves or braids reduce the RFI, EMI interference. Beyond this most cables have elaborate shielding for the same purpose.

Sometimes I wonder if these guys listen to their cables as they seem to get darker, thicker and slower with each twist. Over a year long period I researched and built almost 200 mock ups based on every design I could find. I then posted those findings on a review thread "DIY Interconnect Review". I discovered a lot of surprising things. In that thread I lay out a formula that you may want to try following to build your own cables. I assure you the interconnects your so happy with will be gone from your system for ever, at least that was true in the two friends who replaced magnet wire cables.

At any rate, it is a fascinating issue, and I believe if we all continue discussing what we are finding, we all will evolve in our knowledge and ultimately enjoyment of music!

jd
I saw the chart online that shows values of various materials verifying 5.1 for enamel. I wonder why they work so well for me and make the HF so much better. As I said HF is not only better but there is more of it which helped my overly warm system. Again thanks for the info.

ET
I don't know but they are brighter and "righter" if you will. I had other high dollar cables from Nordost,Kimber(KCTG),AQ Jag,MIT and Cardas. The HF on the Antis in my setup was more present,extended and the cleanest I tried. They livened up my warm sound to here it is more balanced. The connectors on them are modest at best as well compared to nice WBT's. I don't know that the dielectric is that high but if you say so. I'd like to try Mapleshade ribbon in plastic. Thanks for the post.

ET
Hi ET,

I wanted to post these comments, but please understand my motive is to educate, not criticize. Your “magnet wire” setup is simple in design and no doubt sounds cleaner without the shielding in most cable designs. It is not however because you have no dielectric, in fact the enamel coating on the wire you are using has a relatively high dielectric constant of 5.1. A bare wire in a vacuum would be a 1.0 and bare wire in air would be slightly higher. Cotton and dry paper have fairly low dielectric constants of 1.3 and 2.0 respectively.

The problem with copper wire in air, cotton or paper is corrosion and oxidation. Cotton and paper will both retain moisture in a humid climate and actually speed up the oxidation process. This is where poly___ something and Teflon become so useful, but as discussed here, they carry a sonic signature with them. The solution of enamel coated copper wire seems so logical, but in fact it is not a great dielectric at all.

Dielectric constant is a measure of the charge retention capacity of a medium. In general, low dielectric constants (i.e., cotton @ 1.3-1.4) result in a "fast" substrate while large dielectric constants (i.e., Alumina @ 10.0) result in a "slow" substrate. What this has to do with our audio industry is obvious. The lower the dielectric the less energy retention and the easier the signal is carried.

For this reason copper in inherently limiting if we want to use low dielectric materials to isolate wires. In this respect a super thin poly__ something would actually be a better choice than enamel. The issue then becomes finding a super thin covering on copper wire. This is not as easy as one might think, but there are thin tubing that can be shrink wrapped to a bare wire that may prove to be an excellent choice over enamel.

So I suspect the real reason you are happy with the sound of your system is two fold, first the fact that the wires are allowed to be free of added materials like shielding fillers and sleeving leaves a cleaner signal. The high dielectric constant you have may actually have some benefit by being “slowed” making the treble less aggressive, thus less bright.

jd
All my cables are now dielectric free......well except the power cables. But they have a lot of cotton between the cable and dielectric. My interconnects ansd speaker wire and my rewire inside my speaker boxes are all enamel coated solid wire. Best image I have ever heard anywhere.

ET
Tplavas, of all the dialogue here, yours seems most intriguing. If you would be so kind, could you describe your experiences and/or opinions on the various geometries, and their impact on sonics, etc., please?

Thank you!
Joe
Artizen65

crystal oscillator flexed under external voltage causing enough mechanical stress to compromise circuit elements.

200 MHz was generated by electronic chain multiple of crystal or double balanced mixer of sorts and a filter.

PFM? Pulsed frequency modulation?
Dpac,

Since you seem to be into math and proofs I suggust you read this.

http://www.st-andrews.ac.uk/~jcgl/Scots_Guide/audio/skineffect/page1.html

I was going to stay out of this thread after my initial post but it appears that like Sean said one must think outside the box.

Remember there are 3 basic theories electron flow, hole flow and transfer of potential. Which of these theories applies depends on when and where you went to school.

You need to read my previous post and the link. And as for credentials mine are not as impressive as some others on this site. 7.5 years as a Navy electronic technican. Schooling is the equivelant of an AS EE degree. 7.5 years as a digital switch design engineer.

Dpac electronics is PFM period. As an example there was a 100 Mhz reference oscilator in a spectram analizer providing 200 Mhz out of the calibration output. With 4 amplifer stages off of the oscilator. The analizer worked fine in all respects. The problem was a cracked base biasing resistor for the 4 amplifer stages which was in the crystal oscilator circuit. If you can tell me why I might give you knowledge some creedence. Because I already know why and it is not PFM.
I have very great doubts that the RF Transmission line theory that Sean promotes has any relevance to audio. He couldn't convince me with all his words. But then he did something simple...loaned me a couple of speaker cables which I compared with zip cord. That won him the debate. The difference was not nearly as dramatic as some advocates of fancy wire claim, but there was something there. I still doubt his theories, but I went out and bought some speaker cables.
Dpac: One can pick and choose as to what they think matters at audio frequencies, but the bottom line is that Audioholics believe and teach that all reasonably well constructed cables sound the same.

Since we know that all cables don't sound the same and / or provide consistent results under various types of installation conditions, all of their math equations obviously don't cover / explain all of the various aspects that alter cable / component interaction and system sonics. I'm not just picking on Audioholics, but all of those that blindly spout the same "cables are cables are cables" dogma.

As far as using smaller / larger conductors changing the sound of an interconnect, most cables terminate into a component that has an impedance that is hundreds to thousands of ohms higher than the series resistance of the cable. As such, changing the series resistance by even an ohm ( a LOT for a reasonable length cable ) via altering conductor size becomes a moot point. Please remove that factor from your arsenal of responses.

The fact that tonal balance and high frequency resolution, which is attributable to skin effect, are directly altered by changing conductor size, doesn't seem to phase them. One can build identical cables with the same nominal LCR, grades of conductors, grades of dielectric, grades of connectors, etc... with the only variable being conductor size and hear the audible differences. The fact that Audioholics profess that skin effect does NOT come into play at audio frequencies what so ever makes me want to disregard their findings all together.

No matter how much math one does, you can't explain away things that are really happening. When theory doesn't fit reality, which one is wrong???

As far as your comments go about shielding, this typicaly adds capacitance, not inductance. It can also change the velocity of propogation, depending on how the shielding is implimented. In doing so, it effectively changes the path length and loading characteristics that the source component sees, following some of the same principles that apply to transmission line theory.

I'm not saying that audio cables work the same as RF cables, but that many of the same principles can be applied. I also think that, because people like Audioholics / believers in archaic dogma have been conducting most of the testing in this area, we don't have many of the answers that might have otherwise already been explained.

Thinking within the box only lets one see what is in the box. Obviously, the variable results that occur under many different situations of cable / component interaction are OUTSIDE of the box, negating that line of thinking. As such, it leads to limited conclusions and possibilities, hence the problem with the theory not always fitting reality. Sean
>
please show me the article or data you have. Perhaps I am missing something
Why on earth do you need an article or "data" or any other, further erudition? You might measure it, if you wish -- but better still, don't bother:) What may usually happen is noise pick up.

And no, you're not missing anything :) IMO it's not a matter of crucial importance...
I just like to stick to the facts and separate myself from the rampant bullshit from marketing departments.
With you, 100%. You must admit though, sometimes they are very creative. Cheers
Sean:

0"What the audioholics article is/should be really implying is, for example, that connections are critical for, say RF (i.e. it simply won't work) and uncritical for audio frequencies (i.e. it WILL work -- but perhaps badly, i.e. with high losses and noise introduction)."

THis is what you are saying. That article simply points out that dielectric loss tangents/DF are meaningless at audio band frequencies. It's not that an audio connection is uncritical, it's just unnecessary to view it like an RF transmission line. A ~50 kHz signal has a wavelength of 1000's of meters (lambda = propV / f ). Please someone, explain to me why anyone thinks this scenario should be treated the same as one where the conductor length itself is at or bigger than the wavelengths traveling on it.

That is why it's effectively DC (from a tl standpoint) on a wire of typical home cable lenghts.

"Helping me to understand that all cables of reasonable construction and parts quality sound identical"

1)I was trying to say that all cables do not sound the same b/c of , say reflections (vswr higher than 1), but rather lumped (rlc) chraracteristics. Inductnace and mutual inductance are based on geometry and small changes may manifest in different "sounding" (i think more like filtering) cables.

Gregm:
1"Unfortunately, if you use a 50ohm cable on 75ohm connection you'll have reflections even at audio freq"
Hmmm are you sure about this? please show me the article or data you have. Perhaps I am missing something

2"if you create a highly capacitive interconnection, you may get oscillation, and will probably get attenaution of frequencies, even at audio frequencies"

im with you on that. This has nothing to do with TL theory, this is basic lumped circuit analysis of the RLC.
Excessive capacitcane can make sources with high output Z unstable. No big deal. Once again the attenuation is due to 1st order RC filter. Not dielectric absorption or mistmatch

3"if you use additional conductors (say for shielding) you will change the electrical charactersitics of your connection and introduce shifts in the transmission;"
I think your partly right: you will add inductance. yes this changes the lumped characteristics. Any filter causes phase shifts but don't confuse this with V/I lag due to VSWR (voltage standing wave ratio).

4"simple: if you use a thin conductor you introduce a higher resistance than with a thicker wire, and possible phase shift in lower frequencies vs higher frequencies -- even in the audible range (try it, it works!)."
Once again you are describing the RLC componenets of a cable. I agree that changing these will change the sound.
Again this is not due to inherent mismatch b/t cable and source or sink.

We should not confuse source output impedance and sink input impedance with characteristic impedance as it applies in RF (freq >>100kHz) signal transfer.

And dudes: I am not trying to pick arguments with anyone. I am not the one who invented the theory. I am trying to relay the facts as i understand them. I sure might get confused myself in the description of them ( i try not but it's early and the java is empty) but they are out there for all to see. I am not a "measurement type" or one who sucks the life out of audio enjoyment. I just like to stick to the facts and separate myself from the rampant bullshit from marketing departments.

All this yak about characteristic impedance, load matching, and dielectric loss tangents (aka dissipation factor) applied to cable in the audio band is akin to applying special relativity when describing the point at which two cars will intersect on the highway
Tssk, tsk, Dpac996, really:).
What the audioholics article is/should be really implying is, for example, that connections are critical for, say RF (i.e. it simply won't work) and uncritical for audio frequencies (i.e. it WILL work -- but perhaps badly, i.e. with high losses and noise introduction).
Unfortunately, if you use a 50ohm cable on 75ohm connection you'll have reflections even at audio freq; if you create a highly capacitive interconnection, you may get oscillation, and will probably get attenaution of frequencies, even at audio frequencies; if you use additional conductors (say for shielding) you will change the electrical charactersitics of your connection and introduce shifts in the transmission; simple: if you use a thin conductor you introduce a higher resistance than with a thicker wire, and possible phase shift in lower frequencies vs higher frequencies -- even in the audible range (try it, it works!).

Etc, ad nauseam.

If I remember correctly, Sean works in RF applications, hence his comment:
Helping me to understand that all cables of reasonable construction and parts quality sound identical will make my life(...) SOOOOO much better
. How nice that would be!
Audioholics?
Since they don't believe that cables make a difference, they should just shut up about it and let us 'delusional' audiophiles enjoy our hobby.
Dpac996: You and Audioholics are absolutely right!!! I recant all of my previous statements, experiences and chalk it up to my ignorance of the "facts". Thanks for clearing all of this up for me. Helping me to understand that all cables of reasonable construction and parts quality sound identical will make my life ( and maybe even yours ) SOOOOO much better. Sean
>
!!!Transmission line theory does not apply at audio frequencies, unless your cable is a minimum of 500 feet long, and even then this is at 100 kHz and 1/10th a wavelength!!!

There is no debating this, not b/c I mention it, but b/c this is physical reality.
Some cable vendors would have you believe that characteristic impedance actually matters at audio bandwidth (do i hear any ee's in the Audience?). What total rubbish.
However, any given cable, coax, twin, twisted pair, will indeed have a characteristic impedance (this is purely a function of geometry and is nothing more than the ratio of voltage to current along the line).
This (Znot), however only becomes relevant when the cable length is longer than a fraction (usually 1/4 lambda) of the transmitted signal's frequency.
The signal frequencies passing through analog interconnects and speaker cables are effectively DC b/c the wavelengths are so long.
All this yak about characteristic impedance, load matching, and dielectric loss tangents (aka dissipation factor) applied to cable in the audio band is akin to applying special relativity when describing the point at which two cars will intersect on the highway (unless your car is a super hopped up red civic with a really fat tailpipe and has a mighty rocket engine), when good old distance = rate x time works perfectly every time....

I am not trying to disagree with anyone, and I did not invent TL theory, i'm just chiming in to remind, or point out, that all this talk about transmission line theory (dielectrics/insulation having appreciable influence beyond stopping our conductors from shorting out) just is not reasonable at analog audio frequencies.

I do think it is possible for such an ill designed cable to hit the streets such that it's basic RLC can affect the signal, but this is different than transmission line issues.

This type of cable might even have a coloration some find pleasant in their system.

for a real interesting (if you are participating in this thread I assume you are interested) and downright truthful (no bs) discussion of the matter check out:

http://www.audioholics.com/techtips/audioprinciples/interconnects/DielectricAbsorption.php
recently i went to radio shack and bought microphone cables which come with balanced ends. installed where resently i was using synergistic balanced. tell you what they sound great tight bass smooth mid and high end. very natural. then i used them on my sub where i was using single ended cables, sub never sounded better very tight and deep bass i am blown away. i have a talon rock sub 1000 watt. the balanced cables made a big diff over single end. very satified.
Trelja,

I don't think we can underestimate the confusion sewn by the cable industry itself. When some cable designers claim that cable "x" in their lineup is more detailed than cable "z" because of some proprietary treatment or improved dielectric, when if fact they've also changed the geometry of cable "x" (but don't mention it), they just add to the confusion of listeners who are lead to think the sonic change is caused by factors that may have very little sonic impact compared to geometry.
JMO.
IMO, there will never be a perfect analog cable. Cable construction variables and system interfaces will always result in some sort of coloration. With digital HDMI interfaces progressing, we no longer need worry about analog cables. In that case, any cheap cable will suffice. As an audiophile junky I will dismiss what I just wrote.
After watching this thread with great interest, the impression I get after it rising and now cooling off is that we STILL know very little about high end audio cabling.

I've seen folks of all manner of approaches and background have theories, but no real knowledge. By this, I don't mean to offend, just that my definition of knowledge is something on a higher plane that what I am reading. So far, only "I've seen this", "I hear this", or "I tested that". Yet, day after day I read how this cable sounds too dull in system A, while another member disagrees, saying it drove his ears to bleed.

Does surface oxidation exhibit a detrimental effect on a wire or not? Doesn't seem as if we're sure - some say yes and some no, both being just as emphatic as the other.

Are those who feel cable geometry trumps all other factors (material, insulation, etc.) the ones who have the real answer???

And, as far as the point of the thread, what do we really know about the effect of a dielectric on things? Is teflon necessarily better than PVC, polyethylene, polyester, kapton, or polypropylene? For at least a decade now, we have been voting yes with our wallets because that is the conventional wisdom, not because we "know" it's true. What about PVDF (Kynar), which has probably the highest dielectric constant of any stable polymer I can think of. How do cotton and silk rate in absolute terms? Why not think about acrylic or wool?

If air is truly superior, while oxidation is to be avoided (for the sake of argument, again, I have no true idea how critical it is), the cost of filling a tube with a gas such as nitrogen (the main component of air apart from oxygen), argon, helium, or whatever to protect the copper from oxidizing is not very expensive whatsoever. After all, they used a ton of nitrogen (or, possibly, 5% hydrogen in 95% nitrogen - forming gas, which is used in a reduction furnace) to anneal the wire, correct?

And, I have yet to touch on copper, silver, gold, alloys of all manner of metals (for example, 55% palladium/45% silver - the most stable conductor in terms of temperature coefficient of resistance, environmental degradation, and the like), aluminum, carbon...

Hopefully, JD's (Jadem6) thread will spur additional research into the subject. His has been the most valuable thread I have seen here in any audio discussion forum in years. It's certainly got me thinking of cable in a very big way.

In my view, we should have come to definitive answers long ago. Not to seem as if I am on a high horse as I've also done just about nothing to advance the craft. Wish I was still a chemist/material scientist in many regards because I know I would devote a substantial part of my time researching all manner of variables.

Wire remains more or less black magic. Not because it is, but due to our fundamental lack of understanding of the subject. Unfortunately, there doesn't seem to have been much in the way of research since the late 1990s. There's certainly no impetus for it, as we're mostly served by ultra niche companies run by folks without the knowledge, training, or money to conduct it, who are making big profit doing things as they are doing them. Why change? WE certainly aren't demanding it.

As much of a subjectivist as I am, there is a downside to such thinking being so pervasive in this hobby. We are, more or less, simply at the mercy of swapping products in and out of our systems, not knowing how they will sound.

We probably should be at the point where we say this cable will tame brightness, and this one will give you a bit more bass impact and on and on. And, because we truly do not understand why one cable sounds better than another we are apt to pay hundreds and thousands of dollars for products that can often be bought for pennies and dollars. The end result being far more consuming of time and money than it probably should be.
A couple of points:

Annealed cables are often annealed in an oxygen free atmosphere (dry nitrogen) specifically to prevent surface oxidation. Many oxidants are semiconductors and may even exhibit diode like effects(remember selenium plate rectifiers?), I think metal oxides in cables are just plain bad news.

Gauge and metalurgy make a difference to my ears, but dielectric absorbtion seems to be the largest contributor to hard or edgy sounds from cables. I've made my own using foamed Teflon as a core (more air, less plastic) they sound very clean but not as warm as the better (read expensive) commercial cables.

The differences in sound are subtle and the more revealing the system the easier they become to hear. I have not had the experience of being able to hear differences between interconnects on any mass market equipment. i.e. at least some nay sayers will not in fact hear any interconnect differences on their systems because the cables are not the weakest link.

I think almost any system will display speaker wire sonic differences between copper and steel alloy wire (cheap commercial wire, the steel prevents stretch) and a pure copper wire. These differences do not appear to be subtle.
I like Koegz response. After spending all this money on electronics, we expect wire to be the final touch. Wire is like horsepower, to get more horsepower costs money, to get a lot more horsepower costs huge amounts of money. You have to have great resolution in a system to even hear the subtle differences in wire. But, rather than argue on the forums, maybe we should all go listen to more music??? This is like politics, we will never change each other's minds about wire!
in the latest absolute sound krell founder Dan D'Rgostino talks about how he determines that something will sound good. "I like to see waveforms come out the way they look at the imput". why is cable any different? i have a relativly expensive system with a lot of the krell equipment along an extensive vinyl setup. i have listen to some very expensive wire in my system and am hard pressed to hear any real difference. i thought cables were the final thing to make everything sound better to bing it all together, but infact, they seem to be the least important part of my system. to many get cought up in the hype instead of simple common sence.
Corrosion of a conductor can take place due to oxidation, thermal shifts and / or a chemical reaction. Due to the fact that many conductors are directly in contact with a chemically formulated material ( dielectric ) that is exposed to electro-mechanically induced voltages, vibrations and thermal shifts, it is quite possible for the conductor to become corroded within the cable jacket itself. This is due to the chemical make up of the the dielectric breaking down ( due to any of the aforementioned reasons ) and leaching onto the conductors. This is part of what i was discussing above i.e. cables changing sonics / electrical characteristics over time due to internal decay.

Scar: You are wasting your time trying to have a meaningful conversation with this individual. Been there, done that, won't go there anymore. Learned my lesson, as have many others in several different forums. That could be why this party has finally migrated over here i.e. he's running out of other people's sandboxes to dump in. Sean
>
Steve,

Tell me how am I suppose to prove an oxidized conductor sound different from a new conductor in words? Do I need to invite you over so we can compare the two for audible differences.
As I stated in previous post that audible differences in analog interconnects cannot be measured, only can be heard, so if you need technical data, and graphs, I don't have them, so this discussion comes to a close.

You ask me to establish that there is in fact an actual audible difference. In order to established that two interconnect can sound different as a fact, you just need to compare two interconnect of different geometry such as a litz design and a single conductor design with small guage and hear for yourself. Same goes for digital interconnect, two can sound different eventhough it's just passing 0's and 1's from one component to another.
You can call my claims as just opinion, but to me they are facts based on the years I've spent DIYing different cable geometry and experiences with different conductors and dielectrics. If there wasn't a difference we would not get all these people on forums asking for opinions on cables.

Scar
Scar972

It seems our point of view is different, you're looking at it from the technical side, mine is from an audiophile talking about audiophile cable.

I don't know what that means, "an audiophile talking about audiophile cable."

You have made a number of objective claims of fact, none of which have been substantiated with any sort of objective evidence or proof.

Some of you sound like many of the electrical types I've talked to where everything has to be proven with numbers and measurements.

Well, when one makes objective claims of fact, the substantiation of those claims must also be objective. If you have no objective substantiation for your objective claims, then you're doing little more than trying to pass off opinion as fact.

Is that what it means to be an "audiophile talking about audiophile cable"? To pass opinion off as fact?

These people will never believe two audio cable can sound different because it can't be measured.

It has nothing to do with whether it can be measured. It has to do with first establishing that there is in fact an actual audible difference between them.

Audio cable is NOT and never an exact science, I repeat NOT. While skin affect does occur at frequencies above 20khz, differences can still be heard.

And here is yet another objective claim of fact. When exactly was this established as fact?

High End cable designers don't come up with a design so that their cable will only sound as they intend after oxidation has occured, they do their best to limit oxidation with the use of Teflon & PE, this is why we don't see many exposed copper in high end cable design.

How do you know this is necessarily the case? How do you know they don't do it simply because many people have been prejudiced against it by people trying to pass off opinion as fact?

My point of all this rambling is, oxidation has to be taken seriously in a high end cable because the signature sound that the designer intended will be no longer be after corrosion occurs. I don't think audiophiles want to spend hundreds to thousands of dollars on a corroded cable anyway.

Now here you are spouting off while demonstrating you don't even know what you're talking about.

First, oxidation and corrosion are not one and the same. Corrosion is a two part process that requires both oxidation and reduction, where material is actually lost.

Copper actually RESISTS corrosion. This is what gives it such high value in applications such as roofing material and water pipes.

As I said in a previous post, the microscopically thin film of oxidation that quickly forms on the surface when it's exposed to air actually acts as a protective barrier against both further oxidation and corrosion.

So please, before you go trying to scare people about "corroded cable," get your facts straight.

se
I can't help but laugh at all the measurement techno-jumbo talk and electrical training with facts to back it up talk going on in an audiophile forum, this hobby is the farest thing from best measurement equal best product. Why do we even talk about spending hundreds of dollars on an audio cable when a $10 interconnect from Wal-Mart measure much better. The capacitance, resistant, inductance numbers of the most respected audiophile cable brands out there such as Kimber, Cardas, XLO, etc. consistently measured worse than some .25¢ coaxial found at the local hardware store. How can an audiophile spend hundred of dollars on a wire and corrosion is not even important? hope someone here agrees with me...
Why do so many love tube amps when a solid state has much less measured distortion? it's never been about the technical side people.
Cardas and Kimber cable measurements are in the same ballpark, why do they sound so different?

Audiophiles are the ones who hear the difference and believe, engineers are the ones who believe the numbers and never hears.

Scar
Tgrisham

If the issue is that the dialectric potentially changes the sound, and oxidation of copper potentially changes the sound, wouldn't pure copper wire covered in something to prevent shorting, and oxidation, be ideal?

Ideal? I dunno. That rather presupposes that if the sound is in fact to be changed, it must be a change for the worse.

Is this all really just a numbers game when you get to the bottom of it?

I've always found it curious that often the same people who think that a SET tube amp, with horrendous amounts of distortion, high output impedance, limited frequency response, etc. sounds absolutely fantastic, but when it comes to something like wire, everything changes. The wire needs to be the most conductive. It must be of the highest purity. The dielectric constant of the insulation must be as close to 1 as possible.

Just seems a bit schizophrenic to me.

se
Steve,

It seems our point of view is different, you're looking at it from the technical side, mine is from an audiophile talking about audiophile cable.
Some of you sound like many of the electrical types I've talked to where everything has to be proven with numbers and measurements. These people will never believe two audio cable can sound different because it can't be measured. Audio cable is NOT and never an exact science, I repeat NOT. While skin affect does occur at frequencies above 20khz, differences can still be heard.
High End cable designers don't come up with a design so that their cable will only sound as they intend after oxidation has occured, they do their best to limit oxidation with the use of Teflon & PE, this is why we don't see many exposed copper in high end cable design.
Many cable brand has it's signature sound, for example the consistent smoothness of Cardas cables, if they don't limit oxidation after a short period of time highs will be affected and the sound is not as George Cardas intended to be.
My point of all this rambling is, oxidation has to be taken seriously in a high end cable because the signature sound that the designer intended will be no longer be after corrosion occurs. I don't think audiophiles want to spend hundreds to thousands of dollars on a corroded cable anyway.

Dazzdax,
Sorry we hijacked your thread with all this rambling.
It's what makes discussion fun!

Scar

Sean

The dielectric becomes more conductive / lossy over a period of time. As such, the electrons DO interact with the dielectric, both in terms of conductivity and magnetic field. The measurements that i mentioned above pertain directly to this subject.

Well, since you didn't provide any information whatsoever about your measurements, there's no way to evaluate your claim.

se
If the issue is that the dialectric potentially changes the sound, and oxidation of copper potentially changes the sound, wouldn't pure copper wire covered in something to prevent shorting, and oxidation, be ideal? Where do the Speltz anti-cables fit into this discussion?
The dielectric becomes more conductive / lossy over a period of time. As such, the electrons DO interact with the dielectric, both in terms of conductivity and magnetic field. The measurements that i mentioned above pertain directly to this subject. Sean
>
Artizen65

Silver has a slightly higher frequency response than copper in the 20hz to 20khz range. Hence why some people perceive silver as being brighter than copper.

This doesn't make sense. Silver being slightly more conductive than copper will mean that skin effect will be slightly worse in a silver conductor than a copper conductor, all else being equal, and therefore have a slightly reduced high frequency response compared to copper.

So lets assume that skin effect exists in the upper frequency range of the audible band 20hz to 20khz. Other than preventing corrosion or oxidation of the conductor the dialectric should be selected for minimum interaction with the electrons in the conductor. It is this reason that air is the best dialectric.

It's not the electrons that the dielectric interacts with, at least not directly. It's the electric field that the dielectric interacts with.

se
Scar

In the world of audiophile where isolation cones, cable lifters, contact enhancers are used, a oxidized conductor would not go over well.

Then I guess it's good that I only worry about what works best for me.

Oxidation shorten the life of a cable when it sound characteristic is changed due to oxidation, yes it does sound different.

Well, given that placing photographs of yourself in your freezer will make your system "sound different," you'll forgive me if I don't consider "sound different" to be of much worth with regard to issues such as the actual physical properties of a cable.

Now, if you could state what the actual change is and how it manifests itself in the signal, that would be helpful.

Your spools of bare copper wire laying around will probaly work for another 40 years, but the quality and sound won't be the same.

Ok, but why exactly would that be the case? What exactly changes beyond what I had said previously that the effective diameter of the wire is a few molecules smaller?

se
Scar,

I am afraid I agree with a lot of what Steve says. Below is a post with 2 links in it I suggust you read.
http://forum.audiogon.com/cgi-bin/fr.pl?cspkr&1160450950&openmine&zzArtizen65&4&5#Artizen65

What you are refering to is skin effect. Now in my training 100mhz and above is where skin effect really starts to matter. In the link above it deals with skin effect in the audible frequency range. Now I have been told by an EE friend of mine that it is a weak proof.

Not that I now necessarly agree with him at this point in my life strictly from a theoretical stand point not a mathimatical one.

If you start at 1hz the electrons use the whole wire as the frequency increases the electrons migrate to the outside of the conductor. It is not untill your reach the upper frequency's that you actually get into the skin effect theory. It is at these frequencies that the dialectric becomes more of a factor as the electron interaction between the conductor and dialectric becomes more acute.

It is at this point where I might disagree with Steve from a theoretical standpoint. Oxidation will decrease the interaction between the conductor and dialectric and could possibly affect the upper frequency range of the cable. This could have a positive affect or a negitive affect it depends on the frequency and the level of oxidation and or corrosion. IMHO in the lower frequencies it should have no affect at all.

Three major things things come into play with the conductor, material used, purity and quality of the extrusion. Imperfections in the conductor be it purity or vairing raidi of the conductor will affect electron flow through the wire. This will have more of an effect at higher frequencies than at lower frequencies.

Silver has a slightly higher frequency response than copper in the 20hz to 20khz range. Hence why some people perceive silver as being brighter than copper.

So lets assume that skin effect exists in the upper frequency range of the audible band 20hz to 20khz. Other than preventing corrosion or oxidation of the conductor the dialectric should be selected for minimum interaction with the electrons in the conductor. It is this reason that air is the best dialectric. It by nature attracts the fewest electrons from the dialectric or has the least negitive impact by passing stray electrons to the dialectric which allows the electrical signal to stay more completly in-tact as it travels down the conductor. Keep in mind this has a lot more affect in the upper frequencies than the lower frequencies.

Ok I am all tapped out for now although there is more I suggust you read the two links posted in the other thread.
There is also a paper on the same site about wire topology.
Several cable manufacturers are using cotton dielectric. Has anyone identified a sonic signature for cotton compared to PTFE?

I'm not much of a "sonic signature" kind of guy, but I do prefer cotton over plastics, including PTFE. And ultimatley prefer silk over cotton.

One thing worth noting though is that the dielectric constant given for cotton, saying it's even lower than Teflon, is somewhat misleading. The figure that's given (1.3 to 1.4) is for cotton in its raw form, i.e. balls. In its textile form, i.e. woven into thread and fabric, is higher and more akin to that of silk at 2.5 to 3.5.

So for those who are obsessed with numbers, unless you string your wire through a bunch of cotton balls, you're not going to get that 1.3 to 1.4 dielectric constant.

Reference Audio Mods sells braided cotton sleeving in various sizes and vt4c.com over in Hong Kong sells braided silk sleeving (as well as cotton).

And as I mentioned previously, VH Audio sells a 28 gauge solid silver wire with a quad serve of cotton insulation (serve means it's wrapped directly around the wire rather than being a braided sleeving).

se
I have to throw in with Steve, and agree that surface oxidation is not necessarily something to be afraid of.
It's important to remember that most wire used in audio is annealed, and annealing takes place at high temperatures, which can cause functionally significant oxidation within seconds. However, this can be controlled somewhat by manipulating available oxygen levels and cooling times.
When considering stranded wire, such as that used in speaker wire and power cables, a small amount of surface oxidation can actually reduce the negative effects of strand interaction and eddy currents, without the higher dielectric losses seen with strand coatings.

Tim

LeVasseur Audio
Steve,
In the world of audiophile where isolation cones, cable lifters, contact enhancers are used, a oxidized conductor would not go over well. Audiophiles will pay hundreds to thousands for a pair of cable where copper used are of 5 nines to 6 nines in purity, what's the the use of buying this quality if oxidation is not controlled by the designer. Oxidation shorten the life of a cable when it sound characteristic is changed due to oxidation, yes it does sound different. I don't mean it's life is shorten because it no longer work.
Your spools of bare copper wire laying around will probaly work for another 40 years, but the quality and sound won't be the same. Keep in mind, this thread started as differences between dielectric, so people are extremely critical with the slightest change.

Rja,
Cotton dielectric sound slightly less analytical than Teflon, but the ultimate is still the geometry of the cable.
Partsconnexion is another place to buy cotton dielectric wire.

Scar
Several cable manufacturers are using cotton dielectric. Has anyone identified a sonic signature for cotton compared to PTFE?
Agree, audiophiles are often too critical with minor details, but oxidation which occurs at the surface of a conductor must be taken seriously. Electrical signal tends to travel at the surface of a conductor, NOT the center of a conductor as some may think.

It's not so bad as you portray. At audio frequencies the signal current flows through the entire cross section of the conductor, with increasing current density as you move out radially from the center. The difference between the current density at the center and that out toward the surface depends on frequency and the diameter of the conductor.

But so what? As I said previously, all the oxide layer does is effectively reduce the diameter of the conductor by a microscopic amount. This will also reduce its cross sectional area which will have the effect of moving a tad more current toward the center of the conductor and ultimately reduce the effect you're speaking of here.

In other words, the current density throughout the cross section will be very slightly more uniform than it would have been otherwise.

One example is the conductor designed by Analysis Plus, they design a conductor which is hollow in the center.

Sure, that's one approach. Or you can just use smaller diameter conductors. The smaller the diameter of the conductor, the more uniform the current distribution through its cross section will be for a given frequency.

Allowing the surface of a conductor to oxidize over time will change the character of the cable and shorten cable life.

Don't see how it would change the character of the cable in any significant way or shorten cable life. Soon as copper is exposed to the air, it soon gets a surface layer of oxidation. This layer of oxidation actually works to prevent further oxidation

Hell, I have a couple of spools of bare copper wire here that are probably going on 40 years old. Still in good shape.

Oxidation is a reason why air dielectric is not used more often.

I would disagree. But if the reason is oxidation, I'd say it's because people tend to irrationally freak out about it just because they've been told by someone that they should freak out about it

se
Agree, audiophiles are often too critical with minor details, but oxidation which occurs at the surface of a conductor must be taken seriously. Electrical signal tends to travel at the surface of a conductor, NOT the center of a conductor as some may think. One example is the conductor designed by Analysis Plus, they design a conductor which is hollow in the center. Allowing the surface of a conductor to oxidize over time will change the character of the cable and shorten cable life. Oxidation is a reason why air dielectric is not used more often.

Scar