Carver xa-25

I just got my X-over. This X-over can be programmed to different -over frequences. How can i made those modules or maybe buy?
How can i see what frequency the modules are?
Does anybody know where I can purchase additional modules?

Welcome to the forum sdvm. Those are car audio corssovers if memory serves me right and not all that commonly discussed on here. Nonetheless here is all the information I have on it.

Frequency Response ( with Subsonic Filter ) : 20Hz-20kHz (+ 1 dB ) , Subsonic Filter : -3dB @ 13Hz, Crossover Filter : Programmable 18dB/octave slope, Signal-to-Noise ( A-Wtd): 90dB (ref. To 1V rms output), Distortion: <0.1%, Input Impedance: 100 kohms, Max Input Level: 6V rms, Output  Impedance: 470 ohms, Max Output Level: 6V  rms, Operating Votage: 10- 16VDC, Dimensions: 1.5"H x 6"W x 3.25"D , Net Weight: 0.8lbs

Don't have a manual or spec sheet for these, so that is about all I can give you at this time.

Thank you for your information.
The important question is how can i made those program modules?.
I read in the manual there are 16 program modules, 50,60,70,90,100,130,160,200,400,500,800,1000,1500,2000,3000,4000
But how can i see what kind to resistor values is what frequency