QUESTION!!! for those more experienced acoustic guys....
OK, you know when you are watching a video of a sub holding out a say....32 Hz note...The video gives the effect that the sub consistently moving in, then slowly out, then slowly in, then slowly out.......I was watching my mirror the other day when I was bumpin a note like that, and you can actually see that vibration in the mirror, like it changes. Vibrates A LOT, then a little less, THEN A LOT, then a little less....and so on., and you can actually kind of hear it...why does it do this...I will find a vid in a minute if you dont know what im talking about.