I've not met even one builder in 100 that actually knows how to properly make twisted pair wire. Most just assume we just hook a pair of wires to a drill chuck on one end, a doorknob on the other, and then spin until we're satisfied that it is tight enough. Well… this is a problem.
It is a problem because each of the two strands undergoes a LOT of twisting of both the insulation and the inner wire. If (as I used to do) we use a single piece of wire “doubled in half” (that end around the doorknob!), and do the twisting, it turns out that one leg gets wound repeatedly “to the right” and the other “to the left” relative to its core. If it is stranded to begin with internally, this means one wire becomes quite strained by super-twisting, whereas the other becomes unwound, essentially. This is a problem.
There is an interested "made by hand" solution that is easy to do for relatively short hanks of twisted pair. Since none of us designer/builders is in production, having a slightly time-consuming method that actually works is worth learning.
First, cut off two wires, and have them in linear alignment. Not folded in half, a longer wire.
Second, if you can, have a friend or spouse assist. Just for a couple of minutes. It helps, because the process is kind of a 3 to 4 hand operation. Again, use a variable-speed drill that can be controlled to a very low rotational velocity.
Third, start twisting the pair, but have the 'other person' “untwisting” each strand as it rotates on its own independent axis. This is the key, actually. The individual wires are happy to counter-rotate; the resulting twisted pair almost magically resists unwinding when it is released, when it is done. You can lay a piece down, shake it like crazy, and it stays twisted.
Not so for the usual brute-force obvious-man variety. It loves to unravel. The unraveling isn't the problem, it is evidence that the wires within are under significant strain and stress.
Anyway, just an old builder's 2¢.
GoatGuy
$2 a foot? Cheap? I hardly think so. 16 gauge? Thick! Sounds like high-reputation exotic copper to me.
Other thing: verdigris. This “problem” was addressed oh, about 100 years ago. Tinning. I only use tinned wire, whether solid-core or stranded for all electronics projects. Religiously. I also use cheap wire bought in bulk; my dual primary criteria are “sufficient insulation” and “sufficient gauge”. We're working with hundreds or sub-thousands of volts, so insulation is key. But we're also asking our wires to carry audio without coloration by overt resistance-over-distance. Hence why although theoretically AWG 30 wire might do for much of the audio signal path, its a non-starter. AWG 18, 20 and 22 is just fine for most of it.
But then I don't want to start a religious war.
GoatGuy
The thick gauge is need to heat dissipation, the intended 300B build little heat but if the audiophile live in a hot area the situation chance and after afew hours of music the amp will be very hot inside, I have see more than 50ºC in the summer(300B tube).
I will not set the other peoples and his home security for 2th class parts to save afew dollars, I especially recommend do not use recovered wiring, salvaged wiring from scrapped equipment or even computer wiring.
We all know that electricity does not forgive.
No secret by the little I know, I would like to know more.
Twisted wiring in used only in AC wiring, it spends 20% or more of wiring, you should put all the wiring near to the amp metal table to eliminate background noise, hum etc ...
This'll come off as flippant, but it is not intended to be so. Its practical. Try it, ASAP. For teaching people, I recommend "use 3 or 4 feet". I also recommend any of the modern variable-speed drills. Any of them, so long as they will go very slow and aren't otherwise finicky. The hardest part is getting a pair of wires to "stick" in the chuck. Wrapping them with a bit of painters tape works best. Gives the chuck something to grab onto.
If the wires are short enough (less than 2 feet, each) you can do this one-person'd. Drape one wire over your non-dominant arm, the other hanging loose. Use the non-dominant hand to hold-and-pinch the lengthening/twisting junction as it goes. The tighter you pinch, the tighter the twisted pair will become. And there's no fear of "over-twisting" either.
If you have a too-fast drill, then wire friction will heat your pinching fingers. Stop! Next time, use gloves!
The hanging strands will tend to want to get tangled with each other. This you must prevent. (This is why 2 people are SO much better.) To completely make this a 1-person, easy-to-do thing, I ended up taping a pair of 4 foot long PVC pipes together, to keep the wires separate. Put one wire in each tube, then you can do the pinch-the-junction-while-twisting-thing all by yourself. The wires don't bind.
But then I used to do a LOT of chassis hookup. I once was young. I once had hair. Things change. The pair of PVC pipes is “free”, never wears out, and if you don't use (or repurpose) them, always available. You do not need to make a supply of twisty wire. Just make it as you need it.
Just saying,
GoatGuy
No. Wise builders use solid core when they want the wire to stay where they put it, and stranded when they want some flexibility. Very little difference in solderability, and no difference in sound quality.FullRangeMan said:
Yes, old recovered wire may be worn out from passing so many electrons and may have become used to handling different frequencies so will need a long burn-in period for audio use.
Yes, old recovered wire may be worn out from passing so many electrons and may have become used to handling different frequencies so will need a long burn-in period for audio use.
Dâhmn, DF. Wasn't expecting that whilst sipping the ol' cuppa Joe. Now I'm cleaning coffee off my keyboard. You cad. +5 GoatGuy
That particular peculiar effect will have little affect on the sub ultrasonic frequencies involved
Time before I found an abandoned rack-system from "Scientific Atlanta" - Series 2080 Antenna Analyzer.
All external connections and power cables were made of a beautiful teflon litz wire, different AWG. And all inserted into a broad Temflex black teflon schrink.
I use this wire for all my DIY.
Interesting, all power cables in Analyzer were made as star-quad principle.
All external connections and power cables were made of a beautiful teflon litz wire, different AWG. And all inserted into a broad Temflex black teflon schrink.
I use this wire for all my DIY.
Interesting, all power cables in Analyzer were made as star-quad principle.
= skin effect.
Latin pellicula (“small skin or hide”), from pellis (“a skin”) + -cula. Cognate with French pellicule, Spanish película
and, of course, pele in Portuguese for our Brazilian friend!
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