"Why is "strand jumping" bad?"
Strand jumping is related to skin effect that forces current to jump constantly to outside of thick speaker cable (where resistance is lower at higher frequencies). Copper impurities reside on the surface of each strand. Copper oxide is a semiconductor.
Isolating strands prevents jumping but skin effect still exists because strands are still in each others magnetic field (surface is increased though). Here comes helical winding on hollow tube (used by many companies like AQ or AZ) making each strand to be only in magnetic field of adjacent strands. Some companies use flat-woven design or flat copper tape to achieve the same. Flat copper tape is often used in crossovers inductors (for the same reason).
Don't ask me how significant skin effect is because I don't know. From electrical point of view it most likely doesn't have any effect but I don't pretend to know more than cable companies. Solid wire with limited gauge might be an easy compromise. Since skin effect starts at gauge 18 for copper at audio frequencies (20kHz) it is probably safe to assume that even 14 gauge solid wire (like very popular AQ type4) will do job nicely. It has a little more resistance but inductor in a series with the woofer has most likely as much as 0.1 ohm anyway.
On the top of these exotic geometries purity (and type) of metal might play a role as well as dielectric used that changes with the price of the cable with foam Teflon being the best.
My take on this: If it is all placebo effect what is wrong with it as long as it works? You paid for something that sounds better to you whatever the reason. On the other hand I installed once brand new AQ Indigo speaker cable and had for the first hour very muffled sound that changed for next few hours to overly bright to become smooth and balanced within few days. At the same time I read at this forum posts stating that there is no such thing as cable breaking.
Strand jumping is related to skin effect that forces current to jump constantly to outside of thick speaker cable (where resistance is lower at higher frequencies). Copper impurities reside on the surface of each strand. Copper oxide is a semiconductor.
Isolating strands prevents jumping but skin effect still exists because strands are still in each others magnetic field (surface is increased though). Here comes helical winding on hollow tube (used by many companies like AQ or AZ) making each strand to be only in magnetic field of adjacent strands. Some companies use flat-woven design or flat copper tape to achieve the same. Flat copper tape is often used in crossovers inductors (for the same reason).
Don't ask me how significant skin effect is because I don't know. From electrical point of view it most likely doesn't have any effect but I don't pretend to know more than cable companies. Solid wire with limited gauge might be an easy compromise. Since skin effect starts at gauge 18 for copper at audio frequencies (20kHz) it is probably safe to assume that even 14 gauge solid wire (like very popular AQ type4) will do job nicely. It has a little more resistance but inductor in a series with the woofer has most likely as much as 0.1 ohm anyway.
On the top of these exotic geometries purity (and type) of metal might play a role as well as dielectric used that changes with the price of the cable with foam Teflon being the best.
My take on this: If it is all placebo effect what is wrong with it as long as it works? You paid for something that sounds better to you whatever the reason. On the other hand I installed once brand new AQ Indigo speaker cable and had for the first hour very muffled sound that changed for next few hours to overly bright to become smooth and balanced within few days. At the same time I read at this forum posts stating that there is no such thing as cable breaking.