when i was a kid, i used to be a boy scout, and we used to go camping up at camp nihan, saugus, massachusetts. and we'll camp in one side of the lake. this is the lake. there will be another scout troop over here. and we'll have our tent set up here. and we'd tent out here, you know? and here's our troop here. here's their troop over here. they've got their tents. okay? in the daytime, you could yell over to this side, "hey. hey, you guys. how are you doing?" and they'll say, "speak a little louder, i can't hear you." "how you doing?" "fine. how you doing?" "oh, okay." "how's it going?" "oh"--you know these heavy conversations you have, yeah? but it turns out, we could just barely hear each other. but at nighttime, at nighttime-- [whistles] you could hear these guys whispering in their tents. you can hear them so clearly. i can remember that now why the-- "wow, at nighttime, i can hear those guys. "how come i can hear them so good at nighttime? in daytime, i can't." and i didn't know the answer to that. and it took me a long time to find the answer to that. has anyone ever experienced somethi