My advice, be careful in getting the speaker cable for your system as they could be use as a tone control. What i mean is that if your system sound so malambing, you could use a cable with a bright/fast signature, like Nordost cables. Kung gusto mo naman ng medyo mataba with still the smoothness of the highs compared to Nordost, Acoustic Zen Satori comes to mind.
Understand your system and decide the sound you want (malambing, neutral or bright and dynamic). Read reviews of cables to find out their signature sound and this could be your guide which cables to audition.
Typically, Copper will have more body in the mid and lower registers. Silver will sound more extended in the highs, with faster mids and lows. For me the quality os the material, either copper or silver is used. The higher the purity, the better. I also prefer solid core than stranded cable. The downkall of solid core, it is very stiff.
I hope this helps.