Originally Posted by
Pharos
The logistics.
Any even extremely well machined to high finish metal pin, has, under an electron microscope a seriously uneven surface.
These asperities are so pronounced that only a small potion can interact with any interfacing mating part.
Considering that the vast majority of plugs and sockets are made from sheet material forced onto formers, and that there is little guarantee that the result will be anything like conforming with the desired shape, there will inevitably be air gaps in addition to the asperity problem.
I agree with the above re cable ends; I solder the speaker cable together after twisting, and then crush that under the force of the terminal 'nuts' on the speakers or amplifier.
The soft materials allow some compliance from malleability, and will be crushed by the nuts to increase the surface area of contact.
Of course cleaning and re-doing are necessary with time, but this saves a lot of money on expensive plugs and sockets which cannot hope to really mate with a good contact surface area.
The spades above are better, being softer, but they have a screw interface as well, and I would bet that measurement of R would vindicate my approach, which also saves money.
I would have S.Steel terminals, and use a spanner lightly to do up the nuts, further compressing the soldered wire.
BT uses bifurcation, a tapered fork into which one strand is forced. The result apparently gives a more reliable connection than other methods because of a 'cold weld'.