Building balanced interconnects--ideas


Want to make ultra high-quality, 1.5 meter interconnects with Furutech rhodium XLRs. I am open to dielectrics--could use teflon or silk or cotton tubing over ohno continuous cast wire--this is a must-have, either copper or silver. This construction requires solid wire, but what gauges work best in terms of skin effect/time delays? Or, do you prefer stranded wire with a foamed teflon? I would prefer to not use a wire/metal shield. I am thinking a three-wire braid, each wire having its own Techflex carbon braided shield. Which ideas have you had better success with? What type of solder is best? I think we all want some answers and testimony about wire construction--let's lay it down!
128x128jafreeman
I really like the FP-601/602 connectors and I have made several balanced cables with them. I like Cardas Quad Eutectic solder, even though it does have lead in it, I find it works really well at making a successful solder joint.

I would look at bulk preconstructed cable from high end suppliers such as Furutech, Neotech, or perhaps the VH Audio Symmetry. If you have to make it yourself, my favorite is the VH Audio Fine Silver Interconnect recipe and my preference is to use the caulk backer material as the core. If you carefully apply some strain relief at the connector, be careful not to overheat the caulk backer material as you apply heat shrink (the CB will melt), and don't literally pull on the cable by the caulk, you can make a reasonably sturdy, and pretty good sounding balanced interconnect (or rca interconnect) using this method. I have one made with 23awg silver in cotton wire that sounds as good as any silver IC I have had in my system. You can also make it with copper. Although the wire wasn't available at the time I made mine, I would now strongly consider using the VH Audio UniCrystal OCC Copper (or silver) Hookup Wire with AirLok foamed/cellular Teflon Insulation. You can look into things on your own as to how to configure and space the ground wire and shield (or not). Good luck with your project.
Thanks for your advice--I have been looking at VH Audio's recipes--suppose I don't want a shield--do you then run a ground wire soldered end-to-end vs a floating shield soldered at the source end? And please explain what appears to be the preference for a smaller guage wire in these recipes.
Mitch makes some good suggestions. I'll second using the VH AirLok hookup wire. If your system is already bright, use the copper, otherwise use the silver. If you don't really need a shield, just braid three together you'll connect a +, -, and ground on each end. A larger gauge isn't really necessary with the lower current; although, if this is for the connection between the pre and power amps, you may prefer using 21awg.
Here is what Chris at VH Audio says about the cable in balanced use:
This cable design also works excellent for balanced ANALOG cables. It is not neccesary (Most of the time) to ground a balanced connection, so you only need to use pins 2 and 3 on the XLR's. In some systems, Pin 1 will need to be connected at both ends, but this is rare....

* In some situations, you may experience problems with RF interference, due to the lack of shielding on this cable. If think you may have an RF problem, check out the VH Audio Pulsar double shielded interconnect here. This interconnect is available assembled, or the wire is available for you to DIY.
and here is a link to the information;
http://www.venhaus1.com/diysilverinterconnects.html
There are so many options when building these that I could not tell you what you will like best. I personally prefer the somewhat larger 23-24awg wire size (over the 28awg some use) and I like using a single wire for pos and neg. Others like doubling up the negative run for single-ended cables, although you should use the same exact wire/awg for each run of a balanced cable. You can also space a shield away from the conductors if needed. Theories vary on whether to hook the shield at one end, or both ends. If you search here, Audio Asylum, Audio Circle and other sites, you will find more information than you need on diy cables.

IME, for a "made from scratch" diy cable, the configuration shown on Chris' website, when used with the caulk backer and high quality connectors, is hard to beat sonically. I used slightly larger caulk backer (I believe 1/2 inch) for even greater spacing of conductors. If you are worried about the durability of the caulk backer, then try Chris' soft teflon tubing.
FWIW, the whole idea behind balanced line cables was/is to make it so that the cable does not have an artifact- regardless of the cost of the cable.

To accomplish this there is actually a standard that has been in place for the last 60 years or so.

IOW, if you do it right you won't need particularly high-end materials like you do with RCAs.

With regards to the shield, if in doubt attach it to pin 1 at both ends of the cable.
Great information! I am leaning toward three identical wires, each shielded with its own braid. The wire could float in a teflon tube, or it could have a foamed teflon insulaton, such as the VH AirLock. Please tell me this--is a single, solid conductor superior to stranded wire in this situation? And, I am running these interconnects directly from a GNSC Wadia 861SE into monoblock amps, so is the larger gauge more appropriate? Thanks to all for your valued experience.
Don't shield the wires separately. You want the twisted pair to have a common shield.
Thanks, Atmasphere--I am thinking of a carbon-infused nylon braid on each teflon tube, not a metal foil. All are then braided loosely for strength and appearance. I have used Flexo Conductive on power cables, and they are very quiet. How good is Kimber's bulk wire vs Cardas? Neither ever mention Ohno Continuous Cast, but claim to be hyper-pure and soft-annealed, etc. I have to have OOC certified wire by prior experience.
Jafreeman, the issue here is that if you put signal (ground) current through the shield, you can wind up with undesirable effects. In a balanced cable, the signal should only appear between pin2 (non-inverted) and pin3 (inverted) of the XLR. IOW ground should be ignored.

Quite often in high end audio the tenants of the paragraph above get ignored. The result is really expensive cables, or a lot of work put into the cables for no real benefit. If you run separate shields, you will loose a lot of the Common Mode Refection Ratio afforded at the input to the amplifier! IOW use a common shield- it will work better- noise gets into the cable, you **want** it to affect the inverted and non-inverted phases equally! If this does not happen the cable could well have more noise.
Atmasphere--just to clarify, are you saying I should leave the ground pins unused--empty? I understand that pins 2 and 3 carry out what is intended by design in the Wadia 861SE and the ARC Reference 210s I am using. Both of these makers encourage the use of XLR to achieve best sound from their offerings. I now want to use the Duelund 2.0 silver ribbons with silk-impregnated dielectric, which I will individually sheath with FlexoConductive carbon-infused nylon braid--no metal shielding, no dead-end shield, just the 3 individually sheathed conductors in a loose twist/braid over 3 feet. But--bottom line question--are you saying I should leave the ground pins empty and use only the pins 2 & 3 conductors? My system is otherwise well-isolated and free of ground loops via Richard Gray's 240v/120v substation transformer and 1200S for front end. Thanks for your expert advice.
What type of shield material do your suggest? I want to avoid metal of any type, which would mean nothing soldered to pin 1. I hear you saying not to run a dedicated ground wire between pin 1, but to solder a shield to pin 1. If I don't want any metal at all, what should I do with pin 1 for continuity between the CD player and amps? Forgive my ignorance on this.
Jafreeman, seems to me that you have a misunderstanding of what balanced operation is all about.

The origin of the technology was to reduce the effects of cable length; essentially, its introduction made transcontinental and inter-continental phone calls possible. The recording industry seized on the obvious benefits for audio- essentially this technology makes the cables sonically transparent, without having to resort to expensive executions.

It *is* possible to operate balanced line without a shield. To do this though, it is imperative that the receiving end be not just balanced, but also differential.

The bottom line here is that there should be no signal currents flowing through the shield- if there were, it would not be possible to set up a balanced line without one!

Now a lot of high end audio preamp manufacturers don't realize this. This will force you to have either a shield or at the very least a 'drain wire' to make the ground connection.

So if you want to avoid using a shield, then you will have to use a wire, similar to what your conductors are made of. Failing that, IOW if you plan to have no connection on pin 1 at all, your source **must** drive only pin 2 and 3, and must ignore ground. If you have an ARC, CJ or Aesthitix as examples, this simply will not work.

IOW if you 'don't want any metal at all,' as you put it, you will not be having a connection either.

My point here is also that there is no need to go through such an exercise- that was/is the whole point of balanced line operation, and exotic cable constructions do not improve on that unless something else in the mix is gravely wrong.