Report 43229: Homeowner hears possible vocalization and experiences unusual dog and wildlife behavior near Wimberley

I live near the Comal and Hays county line in Texas. This is hill country right on the Devil's Backbone.  This area has lots of heavy oak and juniper with several spring fed rivers; Guadalupe with Canyon Lake near and the Blanco just to the north. September 2012 on a weekend I was enjoying a moonless night packed with stars. I began to hear dogs barking in the distance to the west. More local dogs started barking. I was expecting to hear the coyotes to chime in as they often do on the hill behind my place. Instead my two 100+lb boxer/labs started going nuts. They would not leave the porch to go into the woods as they often do chasing pigs, coyotes or the neighbor's bull.  I had been out on the driveway and went up on the porch. I stood there and tried to get the dogs to go after whatever it was. I tell you the wind was out of the south. Reason being, as I stepped around the corner of the house something big let out a holler, I can not explain. I think it smelled me then. It was close, probably within 20 yards?  Just past where I have cleared all the trees .  The holler, yell was so strong it felt like it shook my insides. Vibrated.  Everything went stone quiet. All the neighboring dogs and mine went totally silent.their hair on their backs was raised and they were locked on something down hill.  Then off to my right, heading up a tight valley I heard wild pigs grunting and then the sound of a couple raccoons?  I couldn't, understand why they would be together?  Then after a few short minutes the dogs up hill started going nuts and then beyond. Like something was moving fast and the dogs were picking up on it.  I told my dogs to go on down the hill into the woods, they did no problem. Never heard again, I wonder what may have happened if I had gone down there without my dogs?