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Wire choice
(06-05-2023, 05:10 PM)Champ81 Wrote: Hi Kevin

Currently I have resorted to heat shrinking the heater wires so they run parallel vs twisted. I use pvc currently.  In my last builds I twisted the Teflon wires but it was way too hard for me. Just to make it easier now I do it in parallel with pvc. It doesn't seem to introduce hum in the last two builds. The only hum was due to the current balancing of the el34s which is now solved through the BMK mod. 

The other issue I am having is for pvc wires the insulation is very fragile and I guess I'm not quick enough to let the soldering iron off at times where the insulation peels back due to the heat. 
But one thing I try to do is make sure there is not an acute bend to the wire to the socket when wiring to relieve the strain. There is also a wire called Prysmian I think from digikey. They seem to be a bit less prone to pvc peeling back. He alpha wires I used peeled back alot easier. There are also eradicated pvc which stay in place. The colours for those were are a more pastel colour.

Why was twisting the teflon wire difficult? I just put one pair of ends in a vice, and the other ends in a drill on low, and it twists pretty easily.  What gauge was the conductor you were using?

I did the same. Twisted it using a drill. The hard part for me was when you need to strip it. Untwisting the ends and make a clean strip. I try to keep it twisted all the way up to the pins and straight through the socket and not looping around it. Keeping it twisted and working with it is challenging. Because Teflon is so slippery.
I usually use stranded 18awg for the power tubes and down to 20awg for the preamp. It is overkill as I can usually use 20awg all the way through but it's just the guage have been using all along.

Maybe I will go back to Teflon for future builds as it is very stiff and will keep its shape.
Hi Guys

When you twist wire, the free ends of each wire are cork-screwing, meaning they are rotating as they revolve around the axis of the twist. This relieves the stress within each wire.

In production environments where a lot of twisted wire is need, there will be two fixtures with a few drill chicks on them arranged in a circle. One fixture will be fixed to a table. The other fixture has a shaft that fits into a drill. The mobile end is round and the drill chucks can spin on their mounts.

Each wire is cut precisely and clamped into the fixed end and into the mobile end. The mobile end is chucked into a variable-speed drill. The operator begins slowly and will have to move slowly towards the fixed end as the twisted wire bundle will be shorter than the wires that make it.

For wiring an amp, the methods described previously are all that is needed and there is no reason not to hook the wire ends in the solder lugs of the sockets. For the amount of twisted wire that is in an amp there is no need to use a drill to do it - just do it by hand and get used to how it works and it becomes much easier when you let the free end be free.

What makes it very easy to assemble is to tin each wire end before inserting it.

There is an analogy between twisting wire and Power Scaling:
You can twist wires many ways and end up with twisted wires, but only if the ends are allowed to corkscrew do you have perfect twisting. Similarly, there are many ways to reduce power or loudness but only one method achieves the desired goal of Power Scaling where the tone remains the same.

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