Apologies for playing the noob here, but how critical is the cross sectional area of the speaker cable. My system is a hifi system where the longest cable run is 12 metres. From what I have seen, 1.5mm2 is the minimum I should be considering. (My current cable is Gale XL105 donated by RS, which I think has a CSA of 0.825 assuming a wire diameter of 0.1mm.) However most cable manufacturers state their 1.5mm2 cables are only suitable for minin and midi systems. What are peoples real world observations? Is 1.5mm2 OK or should I be going for at least 2.5mm2? Thanks for your help.