Hey guys n gals,

I recently added a pair of subs powered by an Alpine PDX-M12 to my stereo which is stock except for a Pioneer AVIC-Z120BT.

Neither the amp or deck allow you to set the low pass filter to an "off" setting so to speak, my only choices are the various frequencies.

Should I try to match these, or just set one of them to the maxand then set the LPF on the other to where I want it to actually function?

I've currenlty set the amp to 400hz and the deck to 80hz and it seems alright though I'm no expert.

 

I'd set the deck to higher and the amp to lower myself.

 

I'd do the opposite...set the amp to accept the largest range (<400hz in this case), and then use your deck to control where you want the crossover point to be. Chances are the deck has more features, is easier to access to make changes or tune it..if that's not the case, then use the one that's most flexible. In case you're wondering the use of the 2 crossovers won't cause a problem as the 400hz point is much, much higher than your actual cross point (in fact most class d amps are only limited to an upper range of 200 hz anyway).