Thoughts on powering my Polk 6x9s in the rear deck with an Alpine mono Class D amp to increase the bass. Using the OEM amp to drive the door speakers (4 Polk coax), will the imaging be OK? Can I use a LOC to connect to the existing rear deck speaker wires and then connect to the mono amp without causing damage to OEM head unit & OEM mp? I can't seem to get much out of the rear deck speakers with the OEM amp. If using a mono amp for the bass freq. then I can turn down the bass to the door speakers and alleviate some of the door rattle. Comments welcome and appreciated.

 

Are you not using the dash tweeters as well? If not your imaging will suffer, all the sound will be at the level of your feet. If you are still using the tweeters, you will suffer from them not sounding like the Polks. I would reccomend getting some Polk tweeters and mounting them in the sail panels behind the side mirrors.

You sure can, I am doing this now, and it's very common. Check out http://davidnavone.com/ for a wide selection of types to fit your needs.

There are several things to say about this.... First, you are probley not getting the output you desire from the new 6x9's because the desire more power. You can power them with the dedicated amp to increase volume, but you still might not get the sound you are looking for, they are only 6x9's afterall. Also, there is a built-in bass boost in the stock amp, adding a LOC and new amp after it will only amplify this bass boost ( ~50hz). The roll off below 35-40Hz is also quite large. I had to use my Audio Control EQX (which is also my LOC) to adjust everything so the bass sounded even and level.