Advice on speaker setup

[Mr. Michael]

Originally I was set on amping a set of Alpine components up front, and some Alpine, or JBL 6x9s in the rear, 100 watts RMS.
Now I think I want a sub. If I just amp the components up front (100 watts RMS), leave the factory 6x9's in the rear, and use the other two channels on my amp to send 300 watts RMS to an enclosed 8" (maybe a 10") sub, will this sound right? Or am I going to be missing some serious midbass with this setup?
The reason behind this is I don't want to run two amps.
Thanks,
Michael

 

[BlkRamRt]

that set up sounds good...you mostly spend your time in the drivers seat so i would amp the front speakers and run the 6x9's off the HU. if you notice it doesnt sound right then amp all speakers and add another amp for your sub.

 

[Caldwell]

i have run a similar set up like this in previous vehicles also. its really not a bad setup for an " economy build " as i like to call it lol. The rear speakers from the factory are limited on mid bass if im correct. pushing 200w RMS in your front sound stage is going to sound pretty damn good, and with a sub in the back for down low feel. i honestly doubt you would notice a lack of sound coming from your rear doors much. I had this experience with only a 250w RMS system in my 08 mazda speed3.