A rattlesnakes rattle is LOUD. There is not really like a slight rattle by them either, its either full bore or nothing. A rattlesnake rattle is loud enough that you would hear it from 100 feet away or more. Also they are really unlikely to rattle unless its super warm or if you almost step on them. I would say unless you saw it then it was probably another species of snake, many of them rattle their tail which would sound like a rattlesnake to someone who hasn't exp. the actual rattle. Think more of cicada's in the morning in terms of a loud noise. Lastly rattlesnakes in the pine barrens wake up late, I won't get into why that is too much but I would say your chances of crossing paths this time of year would be about <1%...unless your on a den. Also given your description of the encounter a rattlesnakes rattle would probably flat out scare the piss out of if you based on your reading. It would have been loud as anything. Two years back I was tracking a rattlesnake in the barrens the pulled my body up onto a slight berm with the aid of a pine tree. Once I got my balance on the berm I heard a 'wooosh' and then the rattle and I instinctively jump about 4 feet back and down the mound. The 'woosh' was it striking at my leg, forunately I had leg protection on. Taught me a valuable lesson when tracking rattlesnakes, always probe the ground first, especially when you could encounter a snake in the ambush(feeding) position next to a tree/log.