WIRE GUAGES AFFECT TONE/VOLTAGES?

[ViperDoc]

Hi all,

I wonder the effect of choosing larger wire guages in an amp build. For example, all non-heater wires in a Tweed build appear to call for 22 gauge cloth wire. So if I admittedly hate the fraying of vintage cloth wire and build a Tweed amp with 20 gauge solid wire, where will I go wrong? And if any other wires are changed to 18 gauge wire? Anything saying I’d regret it later?

Thanks!

[thetragichero]

cloth wire sounds romantic in marketing material but i think the cloth smells worse when i accidentally hit it with the iron than the various plastic covered wire. i use 16 or 18 gauge wire I've salvaged from old organs.

[voskarp]

What the insulation material is made of doesn't matter much as long as it is enough to contain the used voltage, and not to brittle (so it breaks), other than practicality and looks.

Going up in conductor area is of course OK (going down too much would cause it to act as a resistor, affecting voltage and creating heat), but there could be an issue when using solid core wire in a place with much vibrations (as a combo amp). Especially where the wire is stripped there is risk for unintentionally making a small cut in the copper wire, causing it to break if bent too many times. Multi stranded wire is also a better conductor for higher frequencies, but I don't think that has any importance in an audio amplifier.

One benefit with single strand wire is that it's easier to lead dress.

[wpaulvogel]

22 gauge topcoat wire is the best thing I’ve found so far. PVC insulation strips easily, tinned so it solders quickly and it holds its shape well. Amppartsdirect and Valvestorm selling it.

[maxkracht]

I'm a huge fan of pre-bond wire. It is slightly stiff, easy to shape and route like solid wire, but less prone to breakage from mechanical stress. Also, no twisting and tinning like regular stranded wire. Small Bear, Mojotone, and probably several others carry 20awg with 600v rated insulation.

[R.G.]

Within the ranges of wires you might be tempted to use, there will be no difference in tone or voltages. Any hookup wires between, for instance, 32AWG and 14AWG will be fine for signal carrying and tube hookup purposes. The manual difficulty in managing stripping and routing the wires will be vastly different, of course.

For heaters, you have the added issue of current carrying. Heater currents are in the nearly-to-just-over amperes range. Heater wire is probably better if it's 20AWG or bigger. And for heaters, it's better for noise rejection if you twist the heater wires into twisted pair.

You need to pick insulation to suit the voltages on the wires, whatever your requirements for stripping and soldering are, and whatever aesthetic needs are. It's easy to get 600V insulation in PVC insulation. You'll need a few hundred volts rating on at least the plate voltage supply wires and power supply. I don't know the typical voltage rating of cloth covered. Cloth covered may be more difficult to strip cleanly and neatly, although people seem to think it looks cool, hidden there inside the chassis while the amp operates.

As noted, stranded is much easier to route well. And nicking wires as you strip them is an invitation for a break to form right where you nicked the wires with stripper blades.

[ViperDoc]

Thanks for all your replies.

I picked up quite a bit of Tube Depot’s cloth-bonded insulated 20 gauge solid wire and have been using that recently. The major misgiving I have is that it’s very difficult to tightly and evenly twist solid wire. The stranded 20 gauge wire I used on my only Marshall build was a dream to use, I love that stuff. Glad to know I’m in the safe zone!

[maxkracht]

You have probably heard this trick before, but clamping one end of your wires in a vice and the other in an electric drill usually makes very even twists. I haven't tried it with the tube depot wire you have. If I'm thinking of the same stuff, I would worry about using it for heaters due to the extremely thick insulation. Not sure if it would actually have an effect, but with very thick insulation the conductors might not get close enough to each other for proper hum canceling even if twisted tightly.

[ViperDoc]

You have probably heard this trick before, but clamping one end of your wires in a vice and the other in an electric drill usually makes very even twists. I haven't tried it with the tube depot wire you have. If I'm thinking of the same stuff, I would worry about using it for heaters due to the extremely thick insulation. Not sure if it would actually have an effect, but with very thick insulation the conductors might not get close enough to each other for proper hum canceling even if twisted tightly.

I’ll definitely learn the results of this first hand! Thanks for your input.

Every solid wire pair I’ve twisted with a drill twists unevenly. Stranded twists like perfection.

[pompeiisneaks]

You don't need to twist heater wire very tightly for hum rejection. Fender used to be quite loose/sloppy about it w/o major issues. I've also built an amp with non twisted wires and I got basically 0 hum so long as I used good lead dress to keep the heaters away from the signal wires.

I wouldn't worry too much about the thickness of the insulation.

~Phil

[ViperDoc]

You don't need to twist heater wire very tightly for hum rejection. Fender used to be quite loose/sloppy about it w/o major issues. I've also built an amp with non twisted wires and I got basically 0 hum so long as I used good lead dress to keep the heaters away from the signal wires.

I wouldn't worry too much about the thickness of the insulation.

~Phil

Thanks, Phil!

[Roe]

on a big amp, you might hear the difference between a thin, long speaker cable and a thicker one

[TUBEDUDE]

Thanks for all your replies.

I picked up quite a bit of Tube Depot’s cloth-bonded insulated 20 gauge solid wire and have been using that recently. The major misgiving I have is that it’s very difficult to tightly and evenly twist solid wire. The stranded 20 gauge wire I used on my only Marshall build was a dream to use, I love that stuff. Glad to know I’m in the safe zone!

Have you tried using a drill to twist that bonded solid core? I tie a knot with two lengths and put the knot over an eyehook on the edge of my bench. The two ends go in the drill chuck. Pull ìt taut and spin it as tightly as you wish. If the wires slip out of the chuck a knot there will solve that.

[ViperDoc]

Thanks for all your replies.

I picked up quite a bit of Tube Depot’s cloth-bonded insulated 20 gauge solid wire and have been using that recently. The major misgiving I have is that it’s very difficult to tightly and evenly twist solid wire. The stranded 20 gauge wire I used on my only Marshall build was a dream to use, I love that stuff. Glad to know I’m in the safe zone!

Have you tried using a drill to twist that bonded solid core? I tie a knot with two lengths and put the knot over an eyehook on the edge of my bench. The two ends go in the drill chuck. Pull ìt taut and spin it as tightly as you wish. If the wires slip out of the chuck a knot there will solve that.

I sure did and it twisted unevenly. I use a hemostat to clamp the two wire ends together tightly and hold that will I drill the other ends. 20-guage stranded wire twists like a dream, I can't seem to get the solid core to twist very well. Same results with the cloth wire: garbage.

[pompeiisneaks]

I only use solid strand wire except when it comes in the transformer leads, and have had no problems twisting it nicely with a drill and some pliers to hold it, or put it in my vise etc on the other end. What's the issue you've been having?

~Phil