Thanks for the advice. I don't have the equipment yet but I have the funds to spend.
I might go the long and hard way...
Carputer with good 32bit soundcard and optical out >>optical wire>> Alpine pxa-701 DSP >> AudioControl 6XS X-over >>Symblink wire>> Zapco 750.2 / C2K 4.0X / Sub Amp.
I know, its hard to do and pricy but it can be done.

 

I thought about doing that a while ago when I wanted to do something new. A friend of mine is doing that right now. I ended up just going with a new active setup with some revelators and Max Fidelity tweeters.....although everything is sitting in my closet right now (including my old setup). I still might do the carputer thing, but not for a while.

 

1st, you dont need the audiocontrol xover with the pxa-701..

I would do that "standard" 3-way setup... Run the midbass active and the mid/tweet w/ the passive xover.

Xover the system some where around.. subs 60-70hz lowpass.. midbass from there up to between 200hz-500hz. and the mid/tweet from there up.
In my last system the xover points where approx. sub--->60hz<--midbass-->250hz<--mid/tweet

Put the larger amp on the midbass, smaller one on the mid/tweet.

The one thing you need to look at is, is the passive able to do that? the 4" mid cant have a highpass xover on the low end.