Maybe you first tune in the station driving past some lobster-roll shack just outside Bangor, Maine. You know the music isn't coming from the local FM radio tower a few miles away. Instead, it's being digitally compressed and uplinked from a massive command center in Washington, D.C., bouncing off a pair of Boeing satellites in geostationary orbit high above the equator, and finding its way to a sleek little shark-fin antenna mounted on the trunk. The technology is at best a compelling afterthought, because after the fourth or fifth song, you realize the music speaks to you.