I have the Infinity 6002i in the door panels and a Kenwood KDC-4022 head unit. To power the speakers I am using a Eclipse EA3422 4 channel amp bridged for 2 channel.

I am thinking about adding rear speakers and was wondering if I needed to run them through the amp or would the head unit rear channel amp be enough?

I want to keep the power of the channels bridged if possible.

 

For a test I grabbed the old stock speakers and hung them on the hooks behind the seats. I then ran the wires in parallel to the front speakers. This seemed to work and the balance was not too bad. I guess the balance will depend on the sensitivity of the speakers I put in the rear.

It also seemed to help move the highs from at my feet to about chest level.

 

i recently did this, you do have to work with the gain on the amp or the fader control on the head to get the right balance front/rear when you raise the volume. it's personal preference, but when i did it, i felt the rears were way too loud so i had to dial it down with fader.