you guys miss the entire point of why we use 4 pins, it really seems to have little to do with the issue of 6 vs 12 v. It has to do with grabbing cables and accidently plugging them into other sources. the reason we use 4 pins is that they indicate a power transfer, not a mic or line level. 1/4" jacks are used to indicate line level, XLRs are used to indicate mic level. They are all interchangable if you change both sides, but thats the real reason why everything changes.