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Which Pairs to Twist?

I am going to use a couple of 266N12 Hammond transformers to power some Rod Coleman Raw DC modules (for his V-9 DC modules). If I want to twist the secondary leads to minimize hum, I think I want to twist the Blue with the Red and the Grey with the Yellow. Does this seem correct to minimize hum from the wire pairs? I want the parallel configuration.
Thanks
Dave
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This is really a good topic to consider for all wiring. We want our little antenna(es) to be as poor as possible, neither radiating or receiving, only conducting. The same rules of thumb apply everywhere that's not an actual antenna: current equal and opposite polarity in two nearby (meaning as close as possible to being in the same location, or twisted so that "same" averages out) conductors, no other competing current paths, electrical or magnetic. Obviously important for power supplies, but also important for all signal paths. We can't normally do a full B. Putzeys G-word path, but we can be mindful of the issues involved even especially in our higher impedance, physically much larger, vacuum valve projects.

It is completely do-able to build a single chassis SE valve amplifier with indirectly AC heated valves with noise output inaudible ear-in the-horn on 108dB/1W/1M speakers, so with Rod Coleman regulators you should expect that or better performance with DC heating and good wiring practice. Accept no less!

All good fortune, and seasonal greets,
Chris
 
Yes, there are second order effects, such as the minor differences in winding resistance and differences, etc. Ideally the two windings are in parallel with each other. I was talking first order rule of thumb, which is to minimize loop inductance in a current loop/pathway to avoid forming an air-transformer primary winding that would induce AC signal in the conductors around it. Twisting the two conductors that are within the same current loop minimizes inductance. Inductance is determined by the area within the loop. The second order concerns are far smaller and not really worth dealing with, except the easy one of making the connection at the transformer and having only one set of twisted leads, but this is again, not practical or worth the improvement.
 
No, but yes, they do have RLC, etc.

From AI/Google: In various fields like chemistry, mathematics, and engineering, "first order" refers to a system or process that depends on the concentration or value of only one variable, while "second order" indicates a system that depends on the relationship between two variables or the square of a single variable; essentially, a second order system is more complex, considering additional factors beyond the primary one involved in a first order system.

I was using this terminology pretty loosely- meaning first order is "the big, primary concern that matters by far the most" and second order and below are the diminishing minutia that taper off into the fog.