So does this mean that you are using bell wire interconnects abs speaker cable then?
@gibbsy stated “speaker cable of the right cross section”, and I would add “of Oxygen Free Copper (OFC)”.
The general consensus on here is that 2.5sq.mm (AWG13) cross section, OFC copper is good for runs up to about 15m which is why the Kabekdireckt and Van Damme Blue or all you need. That’s all the spec you need to know. If you really want to do the calculation (if you search you may find an old post of mine) for resistance, capacitance and induction on that size and length of wire you will find the effect they have on the sound (higher resistance=lower volume, Higher induction = bass roll off, Higher capacitance = treble roll off) they are several orders of magnitude lower that your ears can determine (0.5dB change).
I would also add that it typically the preamp section of any amp that determines the majority of the amp’s sound characteristic assuming the power amp section is working within its specified range.