An old hifi-troll enters the thread ;P
Speakercables are the component that ruins sound most, to keep them short as possible minimize loss. An old hifi-legend says that energy only use the outside of the conductor, leading hifi-nuts to think that thin foil-conductors would be the optimal solution.
But the whole legend is wrong, current goes deeper than skin-deep, big area conductors is the optimal solution, short & massive.
Years ago a friend showed me his copperfiol-cables thinking he had found the optimal solution. (after uppgrading his filter-coils wsith CFC-ciols; a lot of folks didn`t understand why the foil-coils sounded cleaner))
After liustening a bit I pushed him to make up a set of solid-core copper cabes to compare, about 13awg. Result: a lot cleaner, more open sound and better dynamics. Why? When using a thin foil-conductor the amp looks into jus that; a thin/flat conductor.(like with a multistranded cable)
Thin cables sounds thin and are dynamic-killers. Take a look inside your amp; see the power-circuits dimensioning? The speakercables shoulkd be at least as thick as that circuit, and allways solid.
Off course a triode-amp playing into a hyper-effective horn system wount need the same leader-area as a powerful passiv fullrange. But the key to weightless dynamics is to uppgrade the complete powercircuit, from powercables (solid!)trafos, speakercables and passive filters. (or avoid the last two :S)
Conclution: find some solid copper, say 10awg or even thicker and listen to what happens to your sytem. If you turn up the volume a bit the copper will open up in about an hour. No more hars "details", cleaner vocals and huge bottom-end power. If the boyttom seems fat; add more copper(!) to improve control.
Have fun!