lowrider,
In a late night daze, I ordered a pair of Fmods, made by Harrison Labs. I got them in a couple of weeks ago and they've been sitting in my truck ever since. With all of the talk of crossovers and such, I guess I thought I'd give them a try. Since getting them, though, I've decided that my little Minuets sound really good run full range, so here the Fmods sit, still in their package.
The ones that I have are the 70hz high pass model with a 12db per octave roll off on the low side. If you want to give them a try, I'll send them to you for the whopping price of the shipping. They were only $30 or so new and not worth my time trying to sell them.
If your setup can accommodate them, they just go inline between the pre and amp (or I supposed you can use them through a tape loup). Cutting the lows going to your amp might just be the ticket for you. And cheaply.