You can’t judge a book by looking at the cover. The secrets are hidden.
You can buy different materials to use, including silver content or even silver cables. Cold welding is actually just the industry standard for how you make cables in bulk.
Interestingly enough, all those you listed are as far as I know, nearly completely impossible to measure at this point in time:
1. cryogenic treatment
2. control of directionality
3. cold welded connectors
4. continuous cast copper and long grain copper
5. silver added to connectors
6. gold added to the silver
7. Highly polished conductors
So for the DIYer, unobtanium. An exclusive feature you cannot make yourself. Cool, does it do anything?
Maybe resistance would be an effect of the cold weld and cable content but we are in the range of milli and micro Ohms.
Of the types of things I would have listed as being measurable and having a possible impact are:
- Cable geometry
- Shielding
- Ferrites or other filtering components used in the construction.
It is my theory, that the most effect people hear is when they are not using an adequate conditioner.