One would think you would feel the thing coming. As a child, I was raised in a house near some tracks and us kids would go out there to throw dirt clods at the train as it passed. (Only one of many things we shouldn't have been doing...) I distinctly remember feeling it rumble the ground from a good 100-200 yards away. To not notice it coming, not only would you have to have that thing turned up way too loud, but you are off in your own world not paying attention to anything going on around you ... even the ground rumbling! I guess if you're jogging you may not feel it coming. That iPod must have been blaring, though.