I replaced head unit, bypassed the factory amp (ran new wires from HU to speaker lines from amp, following this guide), installed new speakers in doors, and everything sounds ok...but, I wasn't expecting the tweeters in the front pillars to work...they are putting out sound. presumably there was a crossover in the front to split sound between tweeters and the door speakers. I guess I figured this was built into the amp, but maybe not? Are there passive crossovers after the speaker leads from the amp output? I basically want to ensure I'm not sending the full signal to the tweeters OR a reduced signal (mids/lows) to the doors (as they are full range speakers). Any guidance/insights appreciated!