I am designing a small two way and I want to remove all frequencies below 100hz. In the "loudspeaker design cookbook" it mentions a low frequency filter but I can't find an equation for one. Can anyone direct me. I also recently finished a 2 way that was compared with Vandersteen 2Ci. All four reviewers thought my design smoked the Vandersteens. It's amazing to me that such nice speakers can be put together for such reasonable $.