DIY Interconnects review


Category: Cables

In an attempt to live up to a comment I made on a thread that was discussing interconnects and the over inflated costs, I agreed to do some research and try to build my own interconnects. I could then use fact in my discussions of the value of the manufactured cables. I did intense research for about four months, reading as much as I could on Audiogon, Audio Asylum, web sights dealing with designs by Chris VenHaus, Jon Risch and Allen Wright. I also attempted to go to all the manufacturers web sites and read what they had as a philosophy. Please forgive me for the length of this post, but it was important to me to be thourogh in my methodology so as to help those reading this understand the mission.

It should come as no surprise to most of you, there are as many opinions on what makes a good interconnects as there are companies. Dispite this fact, most every interconnect made today both profesionally and DIY have common methodogy in construction. Most every design I read about starts with a core, has any number of wires coming in a wide array of materials that are wound around the cord. Then the dielectric is created, again using most any material one can dream of. This is followed by most companies and DIY’s using some type of EMI/RFI sheilding. Then some type of fancy casing is used so that the cable looks nice. The casing is generally connected to the connector with shrink wrap and often some type of reinforcement to allow for the users who pull out their interconnects by the wire and not the plug.

Great I thought! Clearly these are all logical components that are being used, and of course I figured there was some science behind all this construction. In fact Cardas is using the Golden Ratio (first dirived in Ancient Greece) so this must be good. Not only is every wire praportional to the other, but the shielding (all nine layers) are also applied using this ratio. Now don’t get me wrong, The Golden Ratio is often used in my profesion of Architecture, it was conceptualized my DiVince the was incorporated in Michelangelo’s St. Paul’s Cathidal, and it has been used ever sense, but audio cables???

Well I took all the ideas I could find and went off to my (three) local Radio Shacks to buy their entire inventory of gold plated RCA connectors. I also picked up a better solder station, a good de-soldering devise, copper wire of every size as well as robbing my local hardware stores of foam backer rods, Teflon tubing, Teflon tape, cottom rope, poly-something tubing and any other thing that looked cool. Total cost of components was roughly $300 ($20 each pair of interconnects) and enough stuff to supply every friend I know with interconnects.

So my first generations started with the pholosophy that more is better, so I built some interconnects using 14 ga wire twisted around a 1/2” teflon tube. I tried one two and three wires per positive and negitive run in equal and unequal combinations. I then built the same concepts using 18ga, then 22ga, 24ga, 26ga, 28ga and finally 30ga. I then repeated the process using a 1/2” Teflon and 1/2”, 3/8” or1/4” cotton rope. On these mock ups I wanted to hear the wire and core intraction with no other variable so I used only cotton thread to hold the bare wire to the core. In each case I listened for a short time to get some concept of what these designs were doing, but only in comparison to one another. I was not yet listening for musicality nor even technical aspects, only an overall concept. I often dragged my friends into this to get a second opinion, but really this was easy to distinguis.

FIRST MYTH EXPOSED: WIRE DOES MAKE A DIFFERENCE! Do not allow anyone to tell you otherwise. If they clain wire is wire, then they either have no experience with a decent system, or no experience trying cables.

It became clear to me that the thicker wire was woolyer , fuzzier and slower as a general response. I quickly drew my attention to 22ga and smaller wire for the next round of experiments. This round was bringing in a preconceved notion of my own that goes against vertually every cable design I researched. Almost without exception the only concept explored by manufacturers and DIY’s alike is twisting the wire around the core. My friends and I theorized that this allows the cable to be more flexable without fatuiging the wire. (like a spring) Spacing suggestions very, but almost without exception the cables are twisted. I used to own Nordost Valhalla cabling for about five years. The speaker cables are made up of forty very fine conductore that run parrallel to one another. This made me explore running my interconnect conductors parrallel as well. So in my next set of mock ups I tried variouse combinations of cable sizes and wire numbers either twisted or straight. Straight won every time! This was not subtle, it was very clearly less congested, and smoother sounding. The winding tended to make the sound feel constraned and mechanical. My personal explaination is wires running parallel on a two dimensional plane have only one chance to interact. Twisting around a core creates a three dimensional interaction and in sometimes many points of interaction. Someone once said, “keep it simple” and I think this advice fits pefrectly here. It also became clear that a single conductors in each direction was prefered every time over multiple conductors. (One conductor could be multiple stands bound as one conductor) The multiple conductor mock ups tended to be edgier or brighter, so I ended up focused on single conductor designs with 30ga or 28ga positive wires and 20ga to 24ga negitive as my prefered sound. I also determained I much prefered the cotton core to the Teflon.

SECOND MYTH EXPOSED: TEFLON SOUNDS BRIGHT! There has been quite a bit of discussion over the past couple years regarding the posibility that Teflon is adding a brightness, or a ringing to the sound of cables. This was bourn out in my mock ups to hold some validity; so next up was determaining what the best dielactric might be. I tried Teflon plumbers tape, cotton, paper, electrical tape and even wool on bare wire, teflon cased wire and enameled wire.. Again I tended to like the cotton, and it became even clearer that Teflon was an issue. Next step was to determain sheilding (if any) Now I know much has been talked up by manufacturers about sheilding, and I supose if you live next to a radio transmition tower… but if you look inside your components, wire is never sheilded, and these wires are running in, out and around transformers, power supplies and digital curcuits. I can not think of a harsher enviroment for EMI/RFI than this. So I must admit I entered this stage with serious reservations. I tried woven steel shielding, woven copper sheilding, copper foil wraps, aluminim foil wraps as well as some mock ups based on the Cardas Golden Ratio. Every one of these had some influence on the sound, but in my opinion always negitive. Shielding is a very dificult thing to do in a repeatable fashion for hand made cables, and I suspect one large area of cost for cable manufacturers. I ended up with no sheilding as my prefered direction.

Next up, two parallel wires run at different spacing. I decided on my own that even consistant spacing was important, so I tried a number of methods to build up a larger cotton core. This included multiple cotton ropes tied together, then in some cases covered in a cotton jacket with wire applied to that. Then another layer of cotton jacket… What a hassle, and clearly not repeatable. I did determain that their was a limit to spacing. Wires further than 7/8” apart began to lose cohenrency and naturalness to the sound. Less than 5/8” sounded brighter and more conjested. I settled on 3/4” spacing as the perfect compromise.

THIRD MYTH EXPOSED: INTERCONNECTS DO NOT NEED A CORE! I must be among the dumbest men on this world, luckly I have a lot of company. It finally hit me, interconnects can be flat. This was ground breaking for me. I’m sure everyone else already knew this, but hang in there, I’m a bit slow. I had purchased this 9mm (approx. 3/4” wide when layed flat) cotton sleeving from Audio Consulting. (Way too expenxsive) It comes as a flat sleeve, so I simply took my two wires, now in cotton jackets and sewed them into each folded edge of this tube. This was a sinple easy way to get a constant and repeatable 3/4” spacing for my wires. It also meant the least dieletric interface with material, leaving the majority of the dielectric as air. Air of course is the best dielectric, but bare wire hanging in space equidistant apart is hard to do, so given the makeup of cotton weave, it allows for about 90-95% air, with very little of the cotton even touching the wire. Perfect, NOT! Ever try to attach a cotton sleeve to an RCA connecter with two super fine wires holding it all together? The issue became painfully clear as I began breaking 30ga wire trying to devise a solution.

FOURTH MYTH EXPOSED: THE SCIENCE AND LOGIC OF A CABLE DESIGN IS OUT THE WINDOW THE MINUTE WE TRY TO MAKE THE CABLE INDISTRUCTABLE! Just take a moment and page through your favorite audio magazine and look at all the cables. Heavy outer jackets made from Kevlar, carbon fiber, Poly-something-man-made, indestructible Teflon uncoated… You get the point. Now look at the interface between this less than desirable dielectric jacket and the RCA. Heavy rubber shrink wrap as a minimum is used, often in layers. Air has a dielectric value of 1.0, Teflon is 2.0-2.3, (I know, they say 1.2 but I’m using a scientific table, not “what they say”) cotton is 1.3-1.4 and rubber is at best 3.0, Poly-something –want-a-cracker is 3.0-4.0 and so on. This means they claim to go through all this science and end up using some less than perfect materials because they need to, in order to make them stand up to us, the guys who pull out our interconnects by the wire. “OH YES YOU HAVE TOO, WE HAVE ALL DONE IT!” And yes, it makes sense that any manufacturer would build the product to withstand some abuse. So despite all the careful planning, the connector and wire interface is an issue.

I ended up trying a few designs; the one I settled on (if I felt the need to address this issue) was some very puffy cotton “piping” from a fabric store. (Thanks to my friends wife, I have not been in a fabric store before, there are some very interesting people hanging around in them) I used a ¾” rope cut in half (length wise) and put the flat cotton interconnect in-between the halves. I then wrapped a thread around the rope to hold it together. At the RCA I shrink-wrapped the last four inched of cotton rope to the RCA. This allowed for the rubber to remain as far from the wire as practical. It looks a bit goofy, but it’s remarkably strong. I did not feel the need to go to this extreme and instead pulled the 9mm cotton sleeve over the RCA and put a piece of electrical tape around it. Half the tape’s width hitting the RCA and half hit the cotton, I figured electrical tape was at least twenty times thinner than rubber shrink wrap, so it should have one-twentieth of the impact to the sound.

SO NOW WHAT? Well the design is complete, now I needed to determine the wire material and what RCA’s to use. For RCA plugs I tried Audio Note, Cardas, Connex, DH Labs, Eichmann, Monster, Neutrik, Radio Shack and WBT. There is not a great deal of difference between the Cardas, DH Labs, Neutrik, Monster and Radio Shack. The Audio Note and WBT were a bit more natural and certainly less congested, but in further testing I could not find a repeatable difference between Radio Shack’s $5.00 gold plug and WBT’s $70 connector. To my surprise the Eichmann was quite a step up. The sound opened up with clarity and speed not found in the others. (I should add that I used both the Silver Bullets and the standard copper connectors. I could not hear a significant difference between the $20 and $50 connectors) If anything I may prefer the copper, a bit more natural and not as bright. I guess it all makes sense that the Eichmann sounds different in that they are the only one with a different design. They use a pin for both the positive and the negative connection, so rather than a whole circle of signal connection on the negative it comes to single points. I assume this makes for a cleaner, more effortless signal transfer??? At any rate the Eichmann was my choice. I ended up with one set of silver and one copper out of default. If I had not already owned the silver I would have used copper for both sets of interconnects and saved a few bucks.

Selecting wire was a bit tricky, in that it can cost a lot of money and there are still a lot of variables. Rather than go through the entire process I will skip to the wire I settled on and hope you believe if it’s possible, I tried it! As a very quick overview I’ll make some general observations. Copper tends to be full, rich and makes for a nice neutral sound. Silver adds PRaT and dynamics not possible with copper. Silver also adds clarity and extension not possible with copper. Silver is also brighter, edgier and at times has an artificial tonality on the top end. Gold was the best of the copper and silver without the bright thin signature of silver, and the clarity was even better than the silver. I attempted to use silver on the negative run in order to keep the cost down, but the improvement between gold and silver is substantial, and worth the expense (my opinion) I did not try stranding silver and copper together nor did I try silver coated copper, (like Nordost) so there is plenty of room for experimentation in these areas.

I ended up using all gold wire, and because of cost I made some assumptions (meaning I did not try every combination possible) For the positive run I ended up using three strands of 99.99% pure 30ga gold wire (not twisted but loosely bound together in a 2mm cotton sleeve) and for the negative conductor I settled on one strand of 24ga 99.99% pure gold wire. How I concluded this set up was some trial and error and some faith on the articles I had read that fit my experience to this point. If I had the money I would have tried a cable using three 28ga for the positive run, I suspect this would be even better, but I used what I had already purchased (bulk purchases lower cost substantially) If someone want to buy me wire…

Much has been said about gold having a significantly lower conductance than silver and copper, but given the distance of one meter, it really is not an issue!!! Gold has a very low resistance as do the others, so my selection was based on sonic quality rather than scientific characteristics. The side benefit (but not my reason for choosing gold) is it does not tarnish and therefore sonically degrade like silver and copper.

Sonically gold was clearer, smoother, richer and more natural sounding than the other two. People have claimed gold is slow or too warm. Neither of these comments matches my experience. One reason for using 30ga was the pace it produced in my trials. This held true with the gold as I used it, and as I commented on in the paragraph above I suspect 28ga gold would continue to have excellent PRaT. I also suspect anything heavier would indeed tend to slow and warm beyond my goals. The interconnect I built is every bit as dynamic and fast as my Valhalla’s were, but with a much fuller and richer top end. I have not experienced the warmth issue either; in fact I believe the 28ga gold positive strands would be a possible improvement if it did add additional warmth. As of this writing I am still trying to determine if this is necessary, a bit more warmth would be welcome, but it might be too much if I tied to achieve this. Over the past two weeks I have spent over six hours every day enjoying music I have not pulled out in years. In ever case, I have no thoughts of what more to do or what is lacking. No fatigue at all and so musical! So altering this design might only degrade the success, but it might be better. Money would answer this…

SOOOOOOO you ask. How does it sound? Well thank you for asking, but as often with me, before we go there let me add a couple more comments.

As I said earlier, I owned the Nordost Valhalla cables for many years. Prior to settling on them I auditioned most every medium and high end cable made at the turn of the century. It is no exaggeration to say I became an expert on cables during a two year period of testing cables. I also learned there are a lot of cables being sold today that are inherently flawed sonically. Over the last six years the amounts of cables that have come to the market have increased many times over, and my personal experience has proven that most of these cables are no improvement over their predecessors. As the sonic quality has improved very little, the costs have climbed to an astonishing degree.

This is not to say that there are not some truly magical cables that have been developed. This topic has become the source of heated discussions on this site as well as Audio Asylum. I have heard so many people who call everything they do not agree with snake oil or an illusion. These people I have turned my back on for comments like this neither are mot worthy of answering nor correct. Cables make differences, and I have a very extensive background to back my claims. When I hear someone say they would never pay more than $100 on cables, I roll my eyes. When I hear people claim they can build a cable for $100 that matches the performance of, (fill in the brand) I get physically sick. These comments are made from people who either have very limited experience or a system that is not capable of appreciating what is possible. In fact this entire experiment began from comments like these. People claiming they can build a cable as good as (fill in the blank) are endless. Let me say hear and now, they are right. I too experienced the level of AudioQuest, Cardas, JPS Labs, Kimber Kable, Shunyata or any other brand you prefer. This is not too difficult, but is that the goal, to match the sonic quality of inferior or flawed cable designs? If that is the goal, I can offer any number of design options that will match that of the mass market cable companies. In fact if the goal is to match the performance of 90% of the cables available, then I suggest you can do this for $25.

My goal here, and in my discussions of this topic is to match or better the best Interconnects available. I have invested countless hours and money to build the best system I can afford and/or justify. I spend the time needed to fully understand the topics I discuss here and I offer my opinions to educate not brag or be the top dog. My ego is fine without this audio site, and therefore I enter this hobby for the enjoyment of music. I would hardly classify myself as an equipment junky or an ill informed audio nut.

My personal experience says that Nordost Valhalla’s are the quickest, most transparent cable made. The bass is so highly defined and the impact of the bass is beyond reproach. The downside of Valhalla is it tends to be thin and bright on the top end. My Reference cables today are Kubala-Sosna Emotion. These are the most natural and neutral cable in all frequencies that I have experienced. They are the best overall performer I have ever heard, the super black background, perfect extension and definition are beyond reproach, but they do not carry the slam and dynamics of the Nordost. A truly magical cable is the Purist Dominus line (both Rev B & C, with fluid or Ferox) of interconnects. The midrange and upper bass are so rich and believable they force you to overlook the lack of clarity on the top end and the lack of bass compared to the best in this area. These cables cast a three dimensionality to the soundstage like nothing I have experienced before.

I bring this up not as some have accused me of bragging, but to help you understand what I was attempting to match in this experiment. I wanted the speed, dynamics, bass and slam of the Valhalla along with the naturalness and blackness of the Emotions and the colour, hues and dimensionality brought out in the Dominus. My goal was to combine the three best I have owned. Along the way I discovered the formula for Valhalla’s detail and speed. I discovered a midrange equal to the Dominus and I found a naturalness of Kubala-Sosna but combining these attributes and then bettering it was not as easy.

So here’s the deal, and a source of disagreement with many at this site. People say:

“Cables do not make a difference.” This is wrong, naive and foolish and clearly not arguable in a logical discussion.

“Cable manufactures are overcharging for their cables.” Yes they are crazy expensive but I can not say they are over charging. My simple little cable takes hours to build, and if a guy is to market, travel, inventory, purchase the equipment needed to produce a repeatable product… then I’m not sure they are so inflated. Yes I agree it’s silly, but my design has about $655 in materials, (approx. $300 in 30ga wire, $285 in 24ga wire, $40 RCA’s and $30 in cotton sleeves) maybe eight hours, so what is that worth? If any comment is true it would be the low and mid priced cables is the scam. Charging a few hundred dollars for a $25 value is the rip off. The top end is closer to a bargain. So yes they are all pricy, buy not out of line if a business is expected to make a profit.

“People buy expensive cables to brag or whatever.” Give me a break; people buy expensive cables to improve the sound. Not everyone wants to do what I just did, and yet they deserve the best sound. It is not the consumer’s fault that it costs a lot, we continue to demand more from our systems, and the manufacturers continue to push the designs. It’s just a fact, cables cost money to build.

“You can get the same sound from a DIY cable at a fraction of the cost.” Absolutely correct, I have tried most every cable made over the years, and I can unequivocally state that in my experiments I would be willing to guess I matched most every cable made. That is not to say this is a good thing, but just that I too can build glare, brightness, poor imaging, bloated bass, slow methodical pace… I can also build bloom, warmth, blackness and silence, natural… I can build it all, good and bad, so? So what does that prove? Nothing to me. If I had not heard the Nordost Valhalla, and the Kubala-Sosna Emotion and The Purist Dominus I would have no way to judge what I was building. If all I had heard was a Cardas Golden Reference, then I guess I would be satisfied when I had duplicated it. It is not right to chastise those who continue to explore the possibilities just because someone thinks cables are too expensive.

We can not judge life without experience. How do you know you’re happy if you have never been sad? How can you judge success until you have failed? You can not, and it hold true in audio too. Without having heard most every cable made, I could not properly judge the results, and thus I could not have ended where I am. So for those who choose to pock the fire, fine, but it is you that is missing out, not me…

Enough soap-box, now let’s talk about the sound.

The sound is quite close to a perfect blend of the three best cables I know of. This design is stunningly fast, excellent slam, highly emotional, very full and rich, fully open and extended. The imaging is tight with great depth, dimensionality and soundstage. The background is more liquid and blacker than any cable I have experienced. The clarity is the best I have ever heard. There is a tonal richness that is hard to believe. Piano is tonally perfect although one of my local A’gon friends wants a bit more bloom around the notes. The colour and hue around all stringed instruments is so perfectly natural and portrays an endless palate of tones.

To this point I still had one complaint, the high frequencies although fully extended and extremely clean, had a slight haze remaining around the highest frequency notes. This haze was not apparent when compared to the other cables; it only became apparent when I tried one more component in my design. I used a Bybee Slipstream Purifier ($75 each) on the positive conductor at each RCA. (Four total or $300 on one pair of interconnects) When I compared the one with the Bybee vs. the one without the haze became apparent. When I added Bybee Slipstream Purifier to the second set of interconnects the top end remained extremely transparent but now without the slight edginess first sensed. The entire presentation took on yet another dimension of realism. This got me to the goal; I now have bettered every single aspect of my system, but all at once! The final produce costs me almost $1000 in materials.

So in the final analysis

As many of you know my health continues to be a problem and time is all I do have. Not only that, but as many also know I have been forced to keep down sizing my system repeatedly over the years. This experiment is successful enough that I will be selling my manufactured interconnects and will be able to pay a few more medical bills!!! As for speaker cables and power cords I do not believe it is as beneficial to build my own, at least right now. My lessons learned in this project do not apply to either the power cords or speaker cables, so it would take another extensive research and a lot more money. My next project is to research power conditioners. This is where I think the true robbery is taking place! So if you care to contact me about the interconnect project or my coming research I would be happy to share what I know

Below are links to some of the research and material suppliers I used. I hope this thread will help settle some of the controversy about cables, and possibly help some find a better cable than they ever dreamt of.

Links:
Chris VenHaus's DIY Silver Interconnects: The original web site for the DIY interconnects
John Risch's DIY speaker cable and interconnect web site
Allen Wright
Allen Wright’s web site
Make Your Own Audio Cables: some reading on DIY cables
Radio Shack Magnet Wire ICs: great sounding diy interconnects on the cheap
The $2.99 Silver Wire Trick: a quick rundown of DIY interconnects by the late Dr. Harvey Gizmo
The Science of Cable Design;
Wire Gauge Calculator
Interconnect and Speaker Cable Design:Part IandPartII at EnjoyTheMusic.com
Dielectrics Constants
Dielectric Constant Reference Guide

Suppliers:
VH AudioSupplies, wire, RCA, casings...
Reference Audio Mod’sAudio Consulting wire and cotton sleeving
Parts ConnexionHuge audio parts supplier [url/http://www.tweekgeek.com/]Tweek Geeks[/url]ERS/ RFI absorbent sheets
Home Grown Audio: Supplier of Teflon insulated silver wire, braided wire, and silver cable terminators
Myron Toback, Inc. Supplier of uninsulated 30 gauge fine silver wire
McMaster Carr:Supplier of Teflon spaghetti tubing for insulating bare wire
A-M Systems, Inc:Supplier of Teflon insulated silver wire
Michael Percy Audio. Supplier of all types of high end, exotic, and esoteric components
Parts Express Suppliers of various wire and cable terminators as well as other components
Scientific Instruments Services, Inc.Gold and silver wire.
Surepure gold, silver, copper wire
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Showing 10 responses by sean

TA-DAAAAAAAH !!!! Persistence prevails!!!

Hopefully, this thread will encourage others to experiment and share their results. Kudo's once again to JD and all of the effort he put into not only undertaking this project, but also the persistence in posting this thread and KEEPING it posted. Kudo's to the others that joined in with supporting the free exchange of info here at Agon. Sean
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While it's great to read about someone reading / learning and doing on their own, i'm sad to learn of your illness JD. Needless to say, i wish you all the best!!!

Other than that, most of what you've been playing with has to do with impedance, EM ( electro-magnetic ) fields and velocity factors. As far as impedances go, what you've found to work well in your system may / may not be universal for others. This has to do with the stability of the circuitry and the nominal impedances of the mating components being used. Not all components share the same stability or mating impedances, so results can vary here.

The nominal impedance of the cable is directly affected by the geometry of the conductors, which also directly effects performance in the area of EM fields. As you mentioned, shielding also effects the sound. Most of the time, this will be in a negative manner due to the improper implimentation of said shield. That's because the shield alters not only the nominal impedance of the cable, but also the EM field AND the velocity factor. As i've mentioned before, shielding IS beneficial so long as it is properly implimented. Having said that, i've also stated that i don't know of any commercially available cabling that is properly shielded : )

As far as the velocity factor goes, this has to due with the conductivity of the signal and how fast / slow the signal travels through the cabling i.e. how long it takes the signal to go from point A to point B through the cable. Once again, this has to do with impedance, geometry, materials used, etc...

Not only do impedance bumps ( small changes in conductor geometry / spacing ) alter the load that the components see, but it also alters the velocity factor in that area too. As such, you can have a cable that has non-linear electron flow ( in terms of speed ) in certain areas of the cabling. Not only can this happen at various lengths, but it can effect certain frequencies more than others.

As such, there's not one aspect of cable design that dictates how things will turn out, but a combination of factors that work together as a whole. You seem to have juggled quite a few variables and come up with something that you like, which is fabulous. I encourage others to try this and i applaud JD's willingness to both share what he has learned and the motivation to undertake such a project !!!

As a side note, i would recommend sticking with conductors that are no heavier than 20 gauge at the very heaviest. That is, use conductors that are smaller in gauge ( higher in number ) than a 20 gauge ( 20, 22, 24, 26, etc... ) at the max. Use solid wire, not stranded. Pay attention to the nominal impedance ( spacing between conductors ) and stay on the inductive rather than capacitive side. Conductor length for each run of conductors should be as close to identical as possible. Using multiple conductors for each polarity makes this harder to achieve, not to mention trying to maintain a consistent nominal impedance via keeping all of the conductors far enough apart from each other in an equi-distant fashion.

If you follow those basic rules, regardless of the type of conductor or dielectric used, even your worst cables will end up sounding pretty decent. Maybe not perfect for your system or to your personal tastes, but at least pretty decent and nothing that you couldn't live with. Obviously, the better the materials that you use and the more consistent that you are in assembly techniques, the better the performance potential.

Keep up the good work JD !!! Sean
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PS... Both Bob and i have cable burners and would be willing to "burn in" a set of these for you. You might be surprised at the "before / after" difference that one can hear when doing this.
JD: To make things as simple as possible, a shield should not interact with the normal rise and fall of the EM field generated by the active conductors within the circuit. Gregm alluded to this phenomena in another thread.

If the shield is placed in close proximity to the EM field that the conductors are generating, distortions are introduced at a non-linear rate. How severe these distortions are has to do with how much the shield changes the nominal impedance of the cabling. This may / may not be consistent depending on either the frequency and / or the intensity of the field that the shield is interfering with. The more effective that the shield is within the frequencies of operation, the further from the conductors it would need to be.

Since shielding is directly related to both coverage area AND material density, some forms of shielding are far more effective and / or ineffective than others at certain frequencies. As a general rule, foils are more effective at very high frequencies whereas stranded braid ( ala the tightly woven braided shield in good coax ) is more effective over a wider range, especially lower freq's.

Combining the two can offer greater advantages over a wider spectrum, but once again, there are many other factors that have to be juggled in order for them not to create as many problems as they may potentially solve. Physical size, high production costs and product flexibility also come into play, which is why many manufacturers / cable companies do NOT market optimally designed cables. Sean
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JD: The EM field of a signal carrying cable will vary with frequency and amplitude. Using specific geometries can reduce the intensity of the field, allowing shields to be placed closer to the conductors. Only problem is, these geometries also alter the nominal impedance of the cable, which may end up being something other than desired.

Like anything else, you have to juggle specific variables in order to achieve specific goals, which are really nothing more than a personal set of compromises. This is much the same as system building, which also results in a personal set of compromises and standards.

Dgarretson: Depending on the specific design attributes of your home-brew foil cables, i have no doubt that they could achieve staggering results. By keeping speaker cable inductance to a minimum, offering a short, straight, single path that minimizes skin effect, it would be hard to go wrong. The only problem with most foils is the lack of surface area i.e. gauge, but this is only a problem with speaker cabling and not interconnects.

As far as interconnects go, that same short, straight single path that minimizes skin effect is still a winner, but you really have to play games with the nominal impedance. The nominal impedance is dictated by the spacing and geometry of the conductors used. Since different mating components will have different nominal impedances, the spacing that works "best" for one set of components may not work optimally for another set. Increasing or reducing the spacing of the conductors can be used to fine tune the nominal impedance, which will alter the transient and bandwidth characteristcs between the mating components.

On top of that, you also have to start worrying about EM / RF interference with this type of interconnect. The geometries that tend to produce the most desirable impedances tend to act as an efficient antenna. In order to minimize potential problems in noisy environments, you now have to introduce other variables that will require further experimentation and design challenges.

Either way, it is GREAT to see others reading, learning, doing and reporting their results here. Sean
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Gregm: Changing the spacing between conductors alters the nominal impedance. The further the gap between the conductors, the higher the nominal impedance. While a higher nominal impedance can act as a "buffer" to the source component loading into the cable ( think "cd player" ), and it doesn't really "hurt" the load component ( think "preamp" ), it can introduce other problems into the equation.

When spacing gets too wide, the inductance of the cable goes up. The higher the inductance, the more potential that there is for the cable to act as a receiving antenna, both in terms of RFI and EMI. Coiling excess cable up can also have a similar effect, as a coil is the most basic form of inductance.

On the other hand, using a cable with a very low nominal impedance can cause a component with a higher than average output impedance to become "loaded down". This not only causes excess current to flow, but can also limit the bandwidth capacity and linearity of the circuit. This can more easily happen with tubed gear, which typically has a higher output impedance. Conrad Johnson gear comes to mind here. Having said that, it can also happen with certain SS gear, especially when very high capacitance / low inductance interconnects are used.

High capacitance / low inductance occurs when you have two conductors in VERY close proximity to each other. The closer that they are, and the more surface area that is in close proximity between opposing polarity conductors, the lower the nominal impedance. As such, a single conductor round wire placed as close as possible to another single conductor wire won't have as low of an impedance as a flat or foil conductor placed next to an identical flat or foil conductor. The wire and foil / flat conductor might share the same overall gauge as a round wire, but due to the wider surface areas of the foil / flat conductor coming into "near" contact with each other, inductance is reduced and capacitance goes up.

Due to the differences in circuit design and impedances that we are dealing with, lower inductance is beneficial to speaker cables. On the other hand, lower capacitance is beneficial to interconnects. As such, using similar geometries and impedances in both interconnect and speaker configurations is a less than optimal approach. That is, cable geometries that are optimized for line level operation are normally quite different than cable geometries that are optimized for speaker level operation.

Honestly, i find it kind of funny that both Goertz and Nordost based their entire lines of cabling on a single yet opposing geometry. That is, all of the Goertz cabling uses a low inductance approach whereas the Nordost uses a low capacitance approach. This is why they can have such different sonic characteristics, even though most people think of them in both being "flat cable" designs. Even though both are "flat" ( per se ) conductors, they are electrically quite different. One will work best as an interconnect while the other will work best as a speaker cable.

There is obviously a gray area where impedances become too high or too low to work in either type of circuit, and some of that will vary with what specific gear is being used. Twisted pair conductors kind of fall into the "universal" category, as it can typically be utilized in line or speaker level applications with pretty good results. What the nominal impedance of the twisted pair is will boil down to the amount of insulation between the actual conductors and the amount of turns per foot that each design utilizes. Sean
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Dbld: Very few components ( i really don't know of ANY in specific ) will work best with a high capacitance interconnect. Having said that, one can use a high capacitance interconnect to tame top end brightness and / or to tailor the response to one's own personal preference. This "softening" will also come at the expense of high frequency dynamics and "airiness", so there is a balancing act that one will end up playing.

Normally, one would want to choose an interconnect that had a nominal impedance that was AT LEAST as high as the output impedance from the source component. This can be found as the output output impedance of cd player as that "loads into" the preamp and / or the output impedance of the preamp as that loads into the amp. In most cases, this would typically be somewhere between 20 - 100 ohms with some exceptions ( like Conrad Johnson for example ) well above that range. Input impedances for most components range from as low as a couple thousand ohms up to several hundred ohms.

This is where things can get tricky. If you've got an output impedance of a preamp rated at 100 ohms, and you're using a "coaxial" based interconnect ( common design ), the nominal impedance of that cable is probably about 50 - 75 ohms ( give or take ). The end result of using this impedance mismatch could end up as ill-defined bass, poorer transient response, a reduction in focus and transparency, narrower bandwidth, etc... This would be most common on designs utilizing Integrated circuits with "measly" power supplies. This can also happen with tubed designs IF the cable is WAY low in nominal impedance and the tubed circuitry isn't all that stable and / or is also current limited.

As such, one can learn how to manipulate various component interactions by juggling input, output and interconnect impedances. When one hears drastic changes in sonics from changing interconnects, that's because they are using the cable as an impedance transformer ( along with some other variables ). Different cables combine with the various input and output impedances of the interconnected devices, therefore producing different electrical characteristics and circuit responses.

While the best design would be to have matching impedances through-out the entire system ( cabling and components ), this is also the most costly to build and toughest to design. It would also limit what components would work well with each other as this is FAR from "industry standard". This is true even though it is the most logical approach when it comes to electronics. As i've said before, many things in audio are "bass-ackwards".

As a side note, electrical characteristics are additive by nature. That means that if one starts off with a short cable that is capacitive ( or inductive ) by nature, adding more length adds more capacitance ( or inductance ). This is why many preamps and / or source components specifically recommend shorter interconnect lengths and / or the manufacturer makes a specific point of stating that their design is stable into any length interconnect. With the latter i.e. suitable for use with longer interconnects, this typically means that the output impedance of the device is quite low and makes use of a reasonably "beefy" power supply / current path.

There's a LOT going on here with tons of variables. This is why so many different opinions exist, even when trying the exact same cables in different systems. Each system / circuit has a nominal impedance and as such, some cables will improve / decrease performance characteristics accordingly. Better designs are less susceptable to cable changes, so long as the cables themselves aren't "crazy" with capacitance and / or inductance. Sean
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Rhyno: You don't have a ground, so there is no way to have "zero" ( ground shunted ) volume. This has nothing to do with the spacing ( nominal impedance ) of the cabling that you are using.

The volume that you do hear is the difference in output levels between the positive and negative legs of the preamp. This tells me that the balanced circuitry inside the preamp isn't running in perfect symmetry. If they were in perfect "balance", there would be no output.

As far as cooking cables on the Mobie goes, you really need to leave them "burning" for at least 30 days uninterupted. I talked to Bob about this several times and we both came to the same conclusions about this. A shorter time may be beneficial, but it may not be quite as good as it can be. Sean
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Rhyno: Not only does the gauge of the ground wire factor into the sonics, but also the proximity that it was placed in comparison to the geometry of the other conductors. Chances are, you changed the nominal impedance of the cable by a good percentage.

As far as silver and teflon being bright, that's a problem with the silver being used. I've got some cabling that uses a teflon dielectric with a silver conductor. I had NO idea that the conductors were silver until pulling it apart. Simply sounded like a very resolving and extended, yet warm and smooth, copper cable.

Then again, i've had silver / teflon cables that sounded very hard and "steely", even after "cooking" the cables for over SIX months on the burner!!! This was one of the very few cables that was "immune" to "burning in" in my experience. The funny thing is that the "shrill" sounding cable is HIGHLY reviewed and cost me three times ( on the used market ) what the other "unknown" silver cable did.

I also have several other silver / teflon cables, all of them ranging somewhere in the middle of those two. Obviously, there are various factors involved here and not all of them are known. Sean
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Silver oxidizes extremely easily and extremely rapidly. While Silver Oxide in itself is still highly conductive, the corrosion on the silver conductors can then spread onto the connectors and adjoining connected surfaces.

Having said that, there's something to be said for simplicity and avoiding complex "man made" materials. Too bad we can't find a way to combine the technology of modern man with the "all knowing" wisdom of God and his creations. Wait a minute. That sounds more like something out of a horror story written by Mary Shelley than an audiophile's dream : ) Sean
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Guidocorona: I surely am not a chemist, nor do i play one on TV, but i was able to find this info on a website:

"Silver metal will oxidize spontaneously upon exposure to free oxygen. This process is commonly referred to as "tarnishing". The chemical reaction describing this proces is shown below.
4 Ag (s) + O2 (g) ® 2 Ag2O (s)
Silver metal is a grayish white color, silver oxide is a black color. This contrast in colors makes tarnished silver appear much different in appearence than untarnished silver. This explains why so much physical and chemical effort is spent in removing the tarnish from silver objects".

For reference sake, that website is as follows:

http://www.chem.umn.edu/services/lecturedemo/info/Silver_oxide.html

Other than that, it would seem "logical" that silver "oxide" is formed when silver becomes highly oxygenated. Like i said, i'm not a chemist and i can't argue the point with any form of conviction, but other sources seem to support my initial statements.

If i'm wrong, i've got no problem with learning why. Of course, some form of technical explanation in an easy to understand English format as a point of reference would be nice : ) Sean
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