DIY SILVER RCA INTERCONNECT CABLES
Mark Houston 
DIY Fine Silver Interconnect Cable
Audiophiles and general listeners can agree and disagree on a whole range of topics with relation to two channel stereo equipment. However, the greatest debate about any component in a hi-fi system typically is about cables. I don't think there is any keen listener who would not agree that you should use good quality cables. I guess the debate really comes down to HOW GOOD a quality and is there really a difference between $20, $200 and $1000 cables?
I believe interconnect cables should be matched to the equipment. My DIY 12AX7 tube preamplifier kit requires a low capacitance interconnect to the power amp. To this end I decided to make my own diy cables.
Fine Silver Wire
Lately, I have been using 0.7 mm un-insulated fine silver (99.99% pure) to act as hook-up wire in power amps and especially preamps. I only use it in the signal path. Generally running spaghetti over it prior to soldering. Because it is only $AU4.70 a metre, I figure why not? I have noticed that my new 12AX7 based preamp sounded particularly precise when I used this wire. Crystal clear, huge soundstage and instruments etched into a deep background with voice which has brought me to tears. So why not make solid pure silver interconnects? Well here's how to do it.
DIY Cable Construction
This is an easy project, extremely satisfying, cheap to do with astonishing results. The design is simple, requiring only three pieces of insulated silver wire, heat shrink tubing and gold plated RCA connectors. Two of the wires, the white and blue are connected to earth at the source connection. The red wire connected to the centre pin both ends. The white wire is NOT connected at the destination end. The white wire is an interwoven shield and does this with out adding (or adding very little) capacitance. The blue wire is grounded at both ends.
The cables require the following:
- 0.7 mm fine silver wire
- 3 X 1.5 mm heat shrink tube, red, white and blue
- 2 X 5 mm heat shrink tube, red and black (or any two colour you prefer)
- silver based solder
- gold plated RCA plugs
- two ferrite snap over chokes 6.5mm diameter or slightly less about 25 mm long
Step by step instructions follow:
- Cut silver wire to required length.
- Cut 1.5mm heat shrink about 1 cm shorter than the silver wire.
- Clean the silver wire with silver cleaning solution.
- Without touching the wire with bare hands feed it into the heat shrink.
- Hold the top wire with pliers while applying the heat. Start at the centre and work top and bottom turning the wire to get an even shrink. Do not put any strain on the tubing at the bottom for when it is hot it will stretch to nothing. Do not over heat this will weaken the tubing. My heat gun is 1600 watts and I hold it about 5 cm from the tubing waving it up and down a little.
- Leave about 2.5 cm at the end then twist about another 2.5 cm together to get the individual silver wires to hold together.
- Cover the twisted end in a wide peace of spaghetti and with a clamp secure the end. Use spaghetti to stop the clamp damaging the soft heat shrink tube. Remove the spaghetti when finished.
Photograph 01: Wire Twisting Jig
Twist 2.5 cm of the three wires together at the end leaving about 2.5 cm untwisted.
Photograph 02: Wire Twisting
Slide 5 mm heat shrink over the twisted wire, leave about 2.5 cm at each end and shrink down.
Photograph 03: Covered Wire
- Slide the screw covers of the plugs on to the coved wire then another 10 cm of the same colour heat shrink. This will be shrunk over the soldered connection last. Make sure you match connector covers with tube colour.
- Decide which end is to be the destination and cut the white wire away just where it pokes out from the heat shrink.
- Label the source cover "S" and the destination cover "D" in permanent pen.
Photograph 04: Prior to Soldering RCA Plugs
- Solder the ends making sure the heat shrink cover is well into the plug and can be clamped with the wires once soldered. Test the cable for shorts.
- Squeeze the connector clamps firmly but be very careful my heat shrink stays very soft and you could easily damage it or short all wires with a heavy hand.
Photograph 05: Soldered RCA Plugs
- Slide up the peace of extra heat shrink you loaded on last. Shrink it to right over the internals of the plug, centre pin and all.
- Screw up the covers and test again.
- Put a layer or two of electrical tape 10 cm from the destination end and snap over your ferrite choke. There should be a little pressure when you snap these into place but do not over crush the cable. Use the electrical tape to regulate the thickness of the cable.
Photograph 06: Finished DIY Interconnect RCA Cables
DIY Cable Results
I found these cables better than the Blue Heavens. I then made a 0.5 metre pair to go from the NAD to my valve preamp. It just got better. Razor sharp image etching, crystal clear highs and deeply textured instrument and voice toning. You will be seduced - be warned.
For more information about this project, see the DIY Audio Project Forums discussion: DIY Silver Interconnect Cables