[pcube]

I'm currently figuring out my options to overhaul my stock sound system and need some help. I'm a noob when it comes to car audio but have been doing my best to research. Been reading through many threads and am a little confused now...

Background: car is a Z4M coupe with DSP but no nav (business cd).

Basic plan is to hook up a pair of comps (tweeter and mid) in the doors. I'm undecided on what to do with the remaining two channels on the HU. One option is to replace the carver subs with 16cm woofers, or to replace the speaker above that with 10cm coaxials. I feel like going with the woofers would be better to cover a larger range of sound?

With this current set up, can I completely remove the stock DSP amp? Or does the amp serve other functions besides providing signals to the speakers? I looked at the wiring diagram and there are pins for muting etc but shouldn't the new HU be able to handle this without the stock amp?

If the amp has to stay, then do I pull new wires out from the HU to connect the speakers, or do I join the correct wires from the input and output harnesses on the amp then use the original wires to hook up the speakers?

Lastly, if I eventually decide to add an amp+sub, am I supposed to splice wires from the DSP amp or do I hook the new set up directly to my HU?