[KevinH1990]

Originally Posted by clickman

One thing, the power comparison I was making was between the old and new head units, not between the new HU and Porsche amp. Probably irrelevant but leads me to another question: I think the original CDR220 was providing more volume coupled with the Porsche amp than I’m getting with the new Kenwood HU. I wonder if there was amplification from both the 220 HU and the amp (cumulativelyw), while with the new HU the amp is fed unamplified sound from the pre-outs so the amp is doing all the work (poorly).

If your car came with the amp in the frunk and door woofers, I believe that the amp did all the work powering the speakers. I base this opinion on my experience wiring the rear speakers I installed in the rear storage compartment. I initially powered them from the CDR 220 head unit and the amplified outputs were unused when I installed the speakers. If I understand correctly, the 6X40 amp that I later installed had circuitry that powered the front and rear speakers and then took the average of the front and rear ouputs and supplied that signal to the door woofers after passing it through a filter that removed the high frequencies.

My current setup uses an amp which is connected to the subwoofer outputs from my head unit. This drives the larger woofers I installed in the doors. This provides improved low-frequency sound.