You cross your subs between 800-900 ??
Does'nt that kind of defeat the purpose of having subwoofers? maybe a mid bass might be more effective

No.

Remember, I am running a pair of 10" subs in a common enclosure. A 10" speaker (of sufficient quality) will produce pretty decent sound up to about 800 Hz. Because of the acoustic coupling provided by the common enclosure, I get the better part of two worlds: the brightness, tightness, responsiveness, and tonality of a 10" speaker, but also with the capability of reaching the same low frequencies that could be attained with a 14.2" subwoofer (if there were such a thing), as the lowest frequency a speaker system will produce is a function of total cone area within the enclosure.

I am of the opinion that a subwoofer can and should do a lot more than go "blumph blumph blumph" every time it plays a drumbeat. The improvement in sound quality in my car is quite significant when I raise the crossover point from the common 100-200Hz up to the 800-900 Hz range. This may be a freak occurrence unique to my particular car and stereo system but I get a warmth and presence that suffuses the entire car once I start getting actual tonality from those speakers, and the higher frequencies, far from sounding muddy, impart a crispness that is lacking when I cross them at 200 Hz.

I had this argument at stereo competitions several times with my old car (another Taurus wagon) and the only way to end it was to put the disbeliever in the car, and then play the stereo, switching the crossover on, and then switching it off so the speaker (single 10" in that car) played full range. Nobody ever argued the point after hearing the results.

tanstaafl.