I'd opined in a previous thread about making a longish balanced cable out of Ethernet Cat5. Was thinking 100ft, give or take, to connect a mixer to a crossover/speaker management box. But, rather than cut off 100ft first, someone suggested trying with the whole length just for proof of concept. Well, here it is. I estimate it at 700ft, give or take. LOL. Used two twisted pairs per channel. Too hot in the garage to mess with it now, but maybe later tonight or tomorrow morning I'll run some music through it.