One of the fights I heard was about 75 yds. away. There was no mistaking the sound. Like stated above it sounded like a stampede. Brush snapping, antler noise and you could hear the rukus they made in the leaves from a long ways away. There was also moaning and grunting noise. This went on for about 3 minutes. After about an hour I couldn't take it. I got down and walked up there. It looked like about a hundred turkeys had gone through the 40 yd area scratching all the leaves up on the hillside. There was areas where all the grass was tore up and small saplings snapped off. Also one drawed some blood, there were several small drops scattered around. One other thing was there were a bunch of other deer running up and down the hillside as this was going on.
I also once watched some smaller bucks sparring that just very made any rattling sound. So it would be hard to tell in some instances.