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The Naked Truth about Interconnect Cables
Now for a bit of practical stuff
[Italian version]
To get serious again, my personal cables have for a long time used 30 Gauge silver-plated solid copper wire with extruded PTFE insulation as conductors.
Sounds expensive? Like the stuff they make the really expensive cables from? The cables with price-tags that look like the serial numbers on Japanese stereo equipment?
Well, how about 12 English pence per meter? That is 30 Deutsche pfennige or 20 US cents. Sounds affordable?
It is sold as "wire-wrap" wire. In the US the source is Radio-Shack, in the UK you can buy the stuff from Maplin, my local electronics shop. For the rest of Europe; I'm not so sure where to buy the stuff, have a look around.
For anything anywhere near this price this is the best-sounding wire I know of.
It is rated at 300V RMS and I use it literally everywhere, where no high currents are needed. That means all internal wiring in Pre-amplification Circuits, their Power-Supplies, power-amplifier input circuits, CD-Players Audio-sections as said everywhere.
In the last year or so I have tried many different geometry's and construction techniques. I have every now and then strayed and tried different conductors. I keep various cheap commercial cables around as a regular reality-check (just in case I start imaging things) and I did do many AB tests with various cables, both blind and sighted.
I have found in all of this two geometry's that worked and where "makeable".
It is Number one - the lanky one with the two parallel conductors
The first geometry is a "linear pair" in either shielded or unshielded form.
I use "Low Loss Satellite" Cable as the Cable "base".
This cable has a plain copper-foil shield, an air-cell polyethylene Insulation (okayish due to the Air) and a solid core center conductor.
Maplin sells the stuff as FT100 for about 90 English pence per meter. I pull the center conductor out of the cable (a bit tricky but manageable) and use the "air-cells" to run two lengths of the wire-wrap wire from one end to the other. For cables of up to about 1.5m all this is quite manageable.
The RCA-Plugs are the largest style of the 4-piece Teflon insulated ones Maplin sells at 1.99 English pounds each.
The former Center-conductor now contains Air (1mm Diameter) and there is the polyethylene and Teflon insulation, making for a decent (but not particular outstanding) dielectric. The Cable is not twisted, but even my Valve-preamp's high output Impedance (around 2kOhm) does not cause any hum pickup.
I do not connect the shield directly to ground, but instead run it out completely isolated. It is connected to a little box with a binding post that is then connected to a Ground-wire of special construction. The Ground-wire is a 50 Ohm Coax-cable with foamed Teflon insulation. The shield is connected to spade connector (Tandy/Radioshack 316-A) but insulated from the center. The center is connected to the binding post in the little Box. The Coax is about 75cm long. This gives us a very high quality capacitor of about 50pf with pretty good RF behavior.
RFI is successfully cut down notably on a version of the same cable without shield, while the sound degradation is minimal.
It is Number two - look how twisted he is
The next cable project is a bit more involved ambitious. I use six parallel strands of the wire-wrap wire wound around a plastic/air core stolen from the FT 100 Satellite Cable in what is termed XLO-Geometry.
Big ThanX to Lance and all the others from the London Live DIY Circle who put me onto this one.
Here the parallel conductors are wound around the core in a pattern where they cross each set in an angle of about 90 degree or more.
The conductor sextets cross each other in such a way that first the first sextet passes below the second sextet and then (on the opposite side of the tube) the second sextet passes below the first. This way, if wound tightly enough, the wire will hold itself on the core.
The best thing to do is to find a dealer who sells XLO Cables and to have a close look.
To make the cable, take a piece of the core of about the length you want the cable you are making to be.
Remove the copper center conductor.
Get 12 Length of the wire-wrap wire, each about 1.3-1.6 times the length your interconnect is intended to end up with. To illustrate; for each 1m (3') length of interconnect, you will need 12 pieces of 1.3 to 1.6 meter (4 to 5 ft) of wire-wrap wire.
I use three pieces each in black and in red (for hot) and another six pieces in white (later cold).
I take each sextet (the lack-red one and the white one) and use electricians tape to make sure the six conductors stay together.
Use the tape only for about 2.5cm (1 inch) or so at ONE end of each sextet. The other remains free.
I then start to put each set of conductors at an approximate 45 degree angle to the core, one on each side of the core. A bit of electricians tape (later removed) holds them in place.
Now (for about 30-45 minutes) it is simply passing the conductor sextets around the core, while observing the spacing/angle and the "over - under - over - over" regime as to how the conductor sextets cross each other.
Every few turns it will be beneficial to pull each single conductor VERY tight (without tearing them apart), so the conductors will stay in place.
You will also find that the ends of cable become tangled. Untangle every few turns and you will be fine.
It is best to have a beer handy and to adopt a very philosophical view of live while making this cable. Just tell yourself that no good sound can come where there was no sacrifice.
My first set was an absolute torture. By now I'm up to speed and it only takes me about two hours to make a 1m pair of interconnects (including termination).
For the termination it is important to either glue the ends of the cable down on the core or to keep the ends as short as possible.
Then terminate the whole cable in such a way that the core will "push" the two plugs apart, thus keeping some tension on the wire.
For your first set you may want to try glue.
But how does it all sound?
First off, these are my personal impressions. They where gained both through sighted and unlighted listening, but are not conclusive or in any way dogmatic.
Generally I have found the XLO style of cable to be superior to foils, twisted and linear pairs, cables of coaxial or triaxial construction and to the Kimber PJB style braid.
Short, the best stuff I had in my system.
Still, the cable is not absolutely neutral, but imparts an ever so slight brightness to the sound. Some people will attribute this to silver-plating. I don't know. The effect is not unpleasant and VERY slight. This brightness is not the "edginess" of many lesser cables. If found it more notable with LP, maybe an effect from the Goldring Elite Moving Coil Cartridge I'm reviewing at the moment?
When comparing the Number two to the Number one interconnect, the main improvements are at the frequency extremes and in sound-staging.
The bass is more extended, as is the treble. There is more "air" around individual instruments, while they are also more clearly "focused" (observation from my own blind listening to both cables).
When compared to the Radioshack/Tandy "Goldpatch" cable, there is a very noticeable muddling of the sound with the Goldpatch.
Vocal sibilants appear to be "clipped" and bass lacks focus.
English is not my native language and I find it much harder to follow complex lyrics when the Goldpatch is in the system (Rhiannon - Fleetwood Mac on Vinyl) or cannot understand them at all.
© Copyright 1998 Thorsten Loesch
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