On the last day of the season in January 2002, I had jumped a buck and circled around to try and cut off one of his possible escape routes. I found a tree and sat down at the base. The buck didn't show, but about 20 minutes later 6 does and 4 fawns came by, four of them so close I could have spit on them. Two of the older does spotted something amiss (my face was bare and my scoped rifle visible) and did the old head down, jerk-back-up routine. When that didn't catch me, one of them tried stomping with her front feet and faking bounding away (stopped after about 20 feet).
When I still didn't move they continued to graze on past me and finally bedded down about 100 yards away on the other side of a draw. When noon came (my time deadline) and I had to leave, I thought, "This is a great opportunity to see what it takes to get their attention." Since I had to get up and spook them anyway, I decided to start speaking, first softly and then louder until they finally heard me and reacted.
Starting with a normal quiet conversational tone, I recited the Gettysburg address. No reaction. So I tried again, this time stronger. Still no reaction. Now I used a projecting voice (reach the back of a big room kinda voice). Still nothing. I finally had to yell, like I was speaking to someone 30 or 40 yards away, before they got up and made haste outa there. It really surprised me how loud I had to be before they took notice.