Beobird: Peter: You don't need $100 wire either - decent power cable will be fine!
I reckon $10!
If you use anolog signals (scart, speaker, interconnects) I recommend GOOD cables. 100 dollars is maybe a bit to much for a good 2x2mtr anolog speaker cable, but you won't get them for 10 dollars !
If we're talking scart cables carrying a multitude of low voltage signals in the same cable then screening is important to prevent crosstalk/interference from other signals or externally. Good quality connectors are also important to ensure a good, reliable, low resistance connection that is immune to tarnishing etc. For speaker cables, given a reasonable length (2m as you say) I'm firmly of the opinion that good connections and a good cross sectional area are all that really counts (not so many years ago the same Hifi press that preach these expensive cables today used to recommend good old solid strand domestic 2.5mm2 twin and earth power cable!
Again, if B&O go to all the trouble to design a pair of world class speakers would they really let them loose on the world with inadequate cables that were going to dent their performance!
BTW it would be interesting to trace the origin of the 10% "rule" - my money's on the equipment/cable manufacturers
Generally speaking, you aren't learning much if your lips are moving.