Cloth insulation looks vintage, I’ve used it a fair amount. If you want to build a authentic looking 50’s or 60’s style amp, it the thing to use.
You need something like this with sharp blades:
[attachment=50]wirestrippers.jpg[/attachment]
Otherwise getting the cloth to trim neatly is a real pain.
In terms of performance, the cloth wire is no better or worst that PVC or Teflon insulated hookup wire. Teflon is good because it does not melt easily.
In a tube amp, 20ga is the usual recommendation for everything except the heater circuit, which should be 18ga. I’ve done several twisted pair 6.3v circuits with cloth insulated wire, it works fine. Just don’t over twist the pair or the cloth covering will split open, not big deal because of the plastic insulation underneath, but it ruins the look. Cloth covered wire comes in a number of colors but if you don’t want to spring for a bunch of rolls, buy a roll of white and color it yourself with a Sharpie.
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