Optimum HU Crossover settings?

[sideswipe]

Heres what I have:

(2) 12" Rockford HX2 subs (RF 800.2 amp)
Infinity components up front (Kenwood KAC-849 amp)
Pioneer TS-A6867 in the rear doors (Kenwood KAC 849)

Im trying to figure out what the optimal HU crossover settings should be. Right now I'm doing it by ear, but I'm thinking maybe it could be better.

I have it set at :

subs: 80 khz (hz?)
front 125khz (hz?)
rear 100khz (hz?)

What do you guys recommend?

 

[MONMIX]

It is your truck , you are gonna spend all the time in it you tune it to what sounds best to you. Just keep playin with it try different CD's.
I will suggest to try this though , send full range to the rears. They are a full rage speaker. Go ahead and give it to them.

 

[nonameputs]

It depends on the slope of the x-overs. But for an example, let's say that both x-overs have a slope of 12db per octave. I would set the front and rear speakers at about 120hz and the subs at 75hz. Then, if you can, use an EQ (or bass bost on an amp) to add 4 or 5 decibles at around 45hz or lower. If the x-over slopes are larger than 12db then make the x-over points a little bit closer, if the slopes are smaller then make the x-over points farther apart.

 

[sideswipe]

Thanks for the suggestions guys, how can I find out what the slopes are?