Chimera Labs Do it yourself - braiding Audio Cable

Braiding Litz Wire Interconnects and Speaker Cables
Starting the braiding process: Measure and cut the wire into the number of strands you need for your interconnects or cables. Add 1.25" to the length of the strand for every foot of cable length. A 3 foot braid requires strands 39.75" long. If you are working in centimeters, add 1 centimeter in length for eve 10 centimeters. A one meter or 100 centimeter braid requires 110 centimeter length strands. Speaker cables can use up to 9 positive and negative strands. Most speaker connectors require two separate connectors. Your final braid length is determined by when you have all the positive strands and negative strands properly realigned to finish your connections. Because of this it is advisable to add 6 inches to speaker cable runs. When we cover the braiding techniques this point will be easier to understand. After you have your strands measured and cut, mount a connector in your fixture. Strip the insulation from one end of the strands. Strip about 1/8" for RCA jacks and about 1/4" for speaker connectors. Using your soldering iron "tin" the exposed wire and the solder points on your connector/s. RCA Jacks - Butt the two tinned positive strands together and solder them to the center pin of your RCA connector. Take one negative strand and solder it to the right side face of the slot in the Jack's shell or body. Solder the remaining negative strand to the left side face of the jack's slot. Make sure each strand has the same length from its solder point to the rear edge of the Jack shell. This is important because you are trying to make sure each strand in the braid is the same length. Take your brush and clean off all the flux residue on all the solder joints. Your next step is braiding the cable. Speaker Cables - Butt the positive strands together and solder them to the positive speaker cable connector. Butt the negative strands together and solder them to the negative speaker cable connector.
Braiding the Cable:
RCA-Jacks - Have your fixture positioned at the front edge of your working surface. Braiding is slow methodical repetitive work. You will find being able to sit down while you braid will help you achieve excellent results. Adjust the height of your work surface accordingly. The flat braiding technique is simple. It consists of taking the outside right strand and passing over strands into the center of the bundle. Then you take the outside left strand and pass it over strands including the one you just brought into the center. Then you repeat the sequence. Braiding a four strand interconnect works like this. LN is the left side negative lead. LP is the left side positive lead. RP is the right side positive lead. RN is the right side negative lead. The braiding sequence is as follows:
	Step One LN is the left side negative lead. LP is the left side positive lead. RP is the right side positive lead. RN is the right side negative lead.
	Step Two Pass RN over RP
	Step Three Pass LN over LP and RN
	Step Four Pass RP over LN
	Step Five Pass LP over RP and RN
	Step Six Pass LN over LP
	Step Seven Pass RN over LN and RP
	Finish At the end of this braiding sequence, the strands are oriented exactly like they were at the start of your braiding sequence. The left negative, left positive, right positive and right negative are in the same position for connecting the braid to the exit RCA connector.
So you can see a braid “sequence” length depends on having the strands back in the same orientation as when the start of your braid. The more strands you braid the longer the braid distance will be between proper orientation. The other factor on braid distance between proper orientation points is how tightly you braid the wire. A loose braid increases the distance. A tight braid decreases the distance. A loose braid provides the best sound performance. Treat wire as if it is a delicate living thing. Wire conductors have a molecular crystalline structure. We know certain processes like extruding, hammering, bending and folding metal disrupts or randomizes its molecular structure. Braiding wire in tight bends can damage the wire's crystalline structure. You may find this difficult to believe, but the difference in sound performance is not subtle. The secret to braiding the wire loose is to control the loop size of your braid crossover. Pass the strand over the over strand or strands so that the loop is between 3/4" to 1" long. Finish a braid sequence so that the wires are back to the proper orientation point. Gently take your hand and wrap it around your braid. Squeeze the braid and pull your hand towards you to compress the braid. Compressing the braid reduces the mechanical resonance of the wire. Look at the wire samples sent with your order. Notice that the wire bends are not tight and the braid still has some air space between the strands. On the samples you will notice that the loudspeaker cable has a 2" long section where the positive strands and the negative strands are braided separately. This is to facilitate making good connections to you components. After 2" the positive and negative strands are combined into a standard braid sequence. This should be done on both ends of the cables. Braiding audio cables using this these techniques offer the home constructor the opportunity to create very high performance cables at great savings. You can also apply these techniques for internal hook up wire. It takes patience, dedication and practice, to develop the skills to braid Litz wire. But the results are certainly worth the effort. Executed properly these Litz cables offer low capacitance, inductance and resistance. They accurately transmit the sound of live music and that's what audio is all about. Magnet wire, especially OFC magnet wire works very well. Vintage Western Electric cloth covered wire does to. The OCCC wire I sell is the best I can find. With magnet and the OCCC wire you have to burn the sprayed on insulation off, but it’s worth it. Stay away from solid core wire with thick plastic insulation. It absorbs the leading edge of the musical signal and low level detail resolution suffers.
History of Litz Braiding
This discussion is to help audio constructors develop the skills to braid their own Litzendraht wire. This form of "Litz" wire was developed in the 1930s in Germany. Since this type of wire construction offered very wide bandwidth with excellent phase performance, its popularity spread to other countries very quickly. Western Electric was using Litz construction in military applications in the early 1940s. True Litz wire construction consists of braiding or weaving a number of insulated conductors. The braid construction is based on taking an insulated strand and folding it back to the center of the strand bundle. Some wire manufacturers will twist a number of insulated strands into a spiral bundle. Originally termed "pseudo" Litz construction, many audio wire manufacturers now call it an "alternative" Litz construction. It is certainly easier to manufacture but it will not achieve the wide bandwidth audio signal transmission performance of true Litz wire. The easiest Litz braiding technique is called a flat braid. It has been popular for centuries. It is used by women when they braid their hair and leather workers to braid sandal thongs or belts. Flat braiding requires a minimum of three strands and can be used to braid a higher number of even or odd strands. The highest number of strands that can be hand braided is determined by the dexterity and skills of the person doing the braiding. Please understand that all my listening evaluations are based on using tube audio products and loudspeakers with simple crossovers and reasonable efficiency levels. I believe AC signal or power transmission is the most appropriate audio application for Litz wire construction. For that reason we will discuss braiding techniques for interconnects, speaker cables. Litz Braid can be used for power cords. On the other hand, the performance of DC power supply and ground lines will benefit from wide bandwidth, low capacitance and DC resistance. Litz construction meets those needs quite well. Since amateur audio constructors do not have to consider labor costs in planning their efforts, they could use Litz braid construction everywhere. This is the form of construction I use in the audio equipment I build. I have been using hand braided Litz construction with some success for years. My experiences have led me to form certain opinions on basic guidelines that should be considered: There is an optimum type of wire for braiding audio Litz wire. Solid core wire is the only type that should be used. Stranded wire defeats or offsets the benefits of Litz construction. Stranded wire is nothing more than a number of bare conductors that are spiral twisted to form the conductor. This type of wire construction has phase anomalies and mechanical resonance that severely degrades audio signal transmission. Litz braiding a poor conductor is an exercise in futility. There is an optimum wire size or cross section for audio Litz wire. I have had my best luck with 24 AWG to 28 AWG wire for interconnects, speaker cable and hook-up wire. Using larger wire sizes for power cord construction may work well. In interconnect, speaker cable and hook-up wire, the larger wire sizes degrade high frequency performance and do not provide the focus, soundstage and low level detail resolution of the smaller gauges. The current transfer capabilities and DC resistance of your Litz construction are based on the wire size and the number of strands you select to braid. In my experience whenever you braid more than 18 strands, the audio performance suffers. I think this is due to the increased mechanical resonance of the Litz braid. Take the time to review the tables found on the anlwire.xls spreadsheet. The first table shows the cross section in nominal circular mills of various wire diameters based on the number of strands used. The second table converts the cross section to the closest AWG wire size you think you need. If you are using the vintage Western Electric wire, interconnects braided with 2 strands positive and 2 strands negative sound the best. This is also true if you use the Chimera Lab's OCCC 25.5 AWG wire. In very low level applications, you may prefer three strands with one strand as a floating shield. The best loudspeaker cable braid depends on your speaker's efficiency. Loudspeakers with 95dB sensitivity or less seem to work well with a braid approximating 16 AWG. This is 5 strands positive and 5 strands negative for the W.E. 24 AWG wire or 9 strands positive and 9 strands negative for the OCCC 25.5 AWG. Loudspeakers with higher efficiency seem to work well with a braid approximating as small as 18 or 20 AWG. Please remember, this is just a recommendation. You hear the greatest difference in sound performance in bass reproduction. You literally select the strand combination that makes the bass sound best to you. The proper length for a braided cable is the shortest length possible that maintains enough distance between components to prevent sound performance degradation. For example, the best loudspeaker cable length seems to be about 3.5 to 4 feet. A shorter cable puts the amplifier too close to the drivers and crossover components. Longer and you just increase DC resistance and add capacitance to mess up your phase performance. The optimum length for interconnects seems to be 1 to 2 meters. I realize many of you have audio systems layouts that use interconnects or loudspeaker cables as long as 20 feet. I just don't get acceptable sound performance out of cables that long. It might be due to the fact that I run all my interconnects, speaker cables and power cords so that they never run or lay on the floor. If you have any of your cables running that way, you are missing a great opportunity to improve your system by suspending or shortening your cables to get them off the floor.
Tools and Supplies
A good soldering iron A sharp wire stripper of the proper size(for the vintage Western Electric cloth covered wire) A solder pot for tinning the wire prior to making a solder connection is optional but nice Your favorite brand of solder A small brass or stainless steel wire brush to clean your solder joints ScotchBrite abrasive pads or a fine toothed file to clean or prep the jack The audio connectors of your choice A fixture to help you solder the wire to the jacks and/or speaker connectors
Some suggestions on connectors:
The best RCA plugs are the ones constructed like the Vampire 800 series which we stock. These plugs have an outer body with a milled slot to provide access to the center positive pin. Since the interconnect Litz braid has 4 strands, the two positive are soldered to the center pin and the two negative strands are soldered to the right and left side face of the slot. You solder the negative strands right at the front edge of the slot, positioning all strands(positive and negative) to ensure they will have the same wire length to the outlet of the connector. The best speaker cable connectors are those that are made of OFC copper. The choice of using spade lugs or banana plugs or bare wire is up to you, but I believe a spade lug or banana plug will offer you the best connection. A simple fixture that you can use for soldering and braiding: Source a pair of cheap RCA jacks and 2 pairs of cheap 5 way speaker binding posts. Find ones that have as little metal mass as possible. This reduces heat transfer when you solder your connections. The binding posts should have metal faces that come in contact with your speaker connector. Find some fiberglass or Bakelite terminal boards. Drill holes in two of the terminal boards to mount the binding posts spaced the standard 0.75" distance apart. Drill holes in two of the terminal boards to mount each one of the RCA jacks. You want to be able to position these in a clamping device or on a piece of plywood so that the RCA jacks are 90 degrees to the front edge of your table or bench top. The binding posts should have their connector mounting surface parallel to your table or bench top. Don't use metal angles or chassis to mount the jacks and binding posts. It will act as a heat sink and makes soldering connections a miserable experience.
Some suggestions on soldering:
Make sure your soldering iron will run hot enough to make good solder joints on the connectors. Modern RCA jacks and banana plugs have thick walls. A 35 Watt or 50 Watt iron will work the best. Use an 1/8" wide screwdriver tip for the RCA jacks and a 3/16" screwdriver tip for the speaker cable connectors. Ideally, you want the iron hot enough so that you can count to 5 seconds or less before the solder flows to make the connection.