insearchofprat,
I really have no experience with cooling audio equipment but am glad you decided to skip liquid nitrogen. It is a bit cumbersome dealing with it. However, it does look cool when you pull things out.
If you are inclined to try, freezer in your kitchen seems like a much more acceptable idea.
Regardless of the recommended way of cooling, theories suggested in some of the posts above leave more questions than answers. You make all the atoms, electrons, or whatever else, settle in their preferred spots. Sound should become divine and maybe it will, based on theories. However, your cable is likely not only metal conductor. It may have some shielding, jacket, whatever else around it. That material is almost certainly not the same as conductor wire and may react slightly different than the metal. What happens then? Is it possible that it will influence the final sound in a negative way? If you look at any of the cable threads, there are heated arguments about all the aspects of cable architecture and then, when it comes to cooling, even contributors to those cable threads seem to forget that there is more to a cable than wire.
Enjoy your experiments, but think critically.