Speakercables are the most misunderstod subject in the whole hifi-buisness. Back in the old days of tubes, single-driver speakers & horns you could use allmost anything. But then when the transistor appeared, watts became cheap and speaker-designers went on manipulating w. lots of components in tiny passive filters & ineffective drivers to get "bass out of shoeboxes" like KEF used to announce. Under-motoriced drivers were stucked into cheap small rectangular shoeboxes filled with glass-wool or foam-rubber to make shure there was no sign of real life dynamics left whatsoever.
No problem, they just "designed" the amps to handle the inefficient filters/speakers. Still using zip-cords for wiring. Stupid fools.
This misleading heritage is still used as the fundament most modern audio-eqipment are designed on, they`re all picking from the same sourche of knowledge.
To get to the point; if there`s one thing that kills the dynamic power from a low utput-impedance SS-amp it`s resistance, even in wery small values. Unlike tube-amps solid state-amps does not "like" cables or passive filters at all. There is one way around this; that`s to simplify passive filters to a minimum and to lower resistance to a minimum by oversizing filtercomponents & speakercables.
A common mistake here is to belive that a lot of tiny straws will flow the same as one huge tube, or in other words think that you can get away by just multilplying the area of some hundred conductors in a multistrand-wire and end up with a great speakercable; that doesn`t sum up.
If you want to get the best out of your SS-amp theres no way around using thick/huge massive conductors to feed the speakers, and as short as possible.
What level of thick am I speaking of? Well, fun begins at around 9awg, but double up and it might really start to swing. Btw, about swing; be aware that a thick solid copper needs a real burn-in. Not for weeks but give it some real beating and you will hear it open up within an hour or so.