Mine measure flat to 12 hz but I realized they are measuring like that when the bathroom door in the back of the room is open. When I close that door it is closer to 17hz. Not that it matters that much, I cross them at 60hz now for movies and for music (I run them full range) my style of music doesn't go that low anyway. It's nice that either way I don't have to worry about a HPF.
Scott, I remember when you were here you were telling me I should keep that bathroom door open all the time, I can't remember what your reasoning was though, do you remember saying that?