By all means wire is critical!! Just how much so depends on a few factors-length, impedance of component driver--the lower the more critical--, and frequency--wire, or loss from it, affects both frequency extremes more than midrange. When u say ur using industrial wire, you don't mean solid core electrical wire do you?? hopefully u mean zip-cord or lamp cord, which is typically18ga. If so, abandon ship immediately&head to your nearest electronics shop--even shadio rack has some half decent stuff4those of us budget constrained working stiffs. Rule of thumb is the less resistance th better. That means thick multi-strand wire, typically minimum 16 guage for standard 4ohm speakers with runs of more than 3feet, thicker,lower guage, if impedance is less than4ohms or if it's a big-assd diameter woofer. Also if your running a lot of power--over 500w--, you'll want thicker wire, say 10 or 12 gauge, depending on how u tolerate lumpy carpet or bulging panels. Shop around, as fu-fu car audio designer wire can get real pricey...hey, they gotta make a living too. For mid-range drivers, u can get away with moderate, say 18 gauge wire. With tweeters, it's back to the thick stuff unless you're using those mostly awful piezo tweets--ok, they have some limited use--in which case u can use your leftover dental floss. After all is said and done, a little known secret is that thin coax cabl--braided part-- has waaaay less resistance than any 10 gauge wire you'll pay big bucks for..prove it with a milliohm meter!!