HOW TO CHOOSE A SPEAKER CABLE?

They should be well built for $14,500 for an 8 foot pair Edward.

If you have the time, this is an interesting article to read.  Lots of good information and different views on what makes a good cable.

https://www.enjoythemusic.com/magazine/viewpoint/0714/oxygen_free_copper_wire_hype.htm

How to choose a speaker cable?

Try them.

That's what the Cable Co or your local dealer is for. It's not really rocket science and they only way to really, truly know is by listening to them In Your System.

From Alan Shaw ( owner and designer of HARBETH speakers)

 … So, the moral of the story is this: the most important factor of the loudspeaker cable that you should select is the amount of metal in the cable core. More metal means lower resistance.

If the core is round (as most are) then the correlation is simple: the fatter the diameter of the metal core the better because the electrical resistance between amp and speaker will be lower.

Thin and really thin cores should be avoided regardless of how exotic the metal material is claimed as the lack of metal in the core conductor will increase resistance. That will reduce amplifier damping, effect the frequency response of the speaker and give unpredictable results that will vary from amp/speaker combination.

Do not be fooled by the diameter of the external plastic sheath: what matters is the metal content of the core. The more the better, without exception….”

+1 for Jpan. There are so many variables that you need to try them in your system. Some people state that power cables are the most likely to improve a system but my experience is I start with the speaker cables then the interconnects followed by the power cables hopefully all from the same manufacturer.