I have a Blaupunkt component set which is basically 5.25" speakers with 1" tweeters, and passive crossover, in my front doors. The frequency range 70 to 22k hz. These are running without any additional amplification off of my OEM ford HU. I'm also running a 12" subwoofer in the trunk with a 400 watt Kicker amp in the trunk. Since I'll get enough bass with my sub. I'm considering adding 300 hz bass blockers to the front door 5.25s. Where should I install the bass blockers? Right before the 5.25 speakers or before the crossovers?