you didn't ask me, but I'll tell you anyway. I usually call areas that are tough to get into with out spooking the hogs out. depending on how close I am to the area I think they will come from determines how loud I call. Usually pretty loud though. Hogs are very vocal and very loud except when just being social. Most of the sounds I've developed for calling are intended to bring them running and most social sounds bring them in slow as curious.
We have documented calling hogs as far as a mile, its difficult to determine how far some have traveled, but I have no doubt we've called them further.
As far as blind calling goes, yes we do some "blind" calling. WE do suspect there are hogs near by or we don't call. If they can't hear you they wont come. Generally speaking we don't call to hogs we can see unless they are on property we can't hunt or they are traveling away from us faster than we can get to them. then We will call to them.
Calling hogs is just like calling any other animal. Sometimes they come sometimes they don't. They will nearly always try to get down wind of the caller. Again try watching our youtube channel to pic up hints. I will be doing a series on calling hogs in the near future. We are working on it now.
https://www.youtube.com/watch?v=pBpdhSHxOpY&list=PL0et1cMOo0BDJiizAY90tD3iZ6dV_4B2J
