I have a 2007 Outback, and I'm working on a modest audio build. Unfortunately, the head unit is integrated with the HVAC, so I'm working off of the factory HU on this build. Like the Impreza line, the Outback has 4CH audio, with no true sub channel. (The OEM sub option just tees into the other channels). I have a $500 budget for the initial set.
Updated 1/28/14 plan:
*AudioControl LC7i - This is an audio processor and LOC I'll be using to convert all existing channels to pre-outs, and can copy the rear channels, adding the sub channel I never had! I heard this in person before and after at the local audio shop, and the difference was incredible. Incredible clarity and audio sharpness.
*Rockford Fosgate R600X5 - 5CH amp with 50W/channel at 4ohm, and a 200W sub channel at 4ohm.
*Pioneer TS-W254R - 10" 4ohm sub. Accepts 50-250W RMS power, right in line with the amp.
*Custom sub box - I'll be fabricating a custom sub box volume matched to the JL sub, and styled similarly to the JL Stealthbox. I have previous fiberglass and woodworking experience, so this should be an approachable project. I'd like to incorporate some utility into the box, so since I have way more room in the fender space than I need for the sub volume, I'll be using the extra space for a power inverter, offering a 110V power outlet, and some cubby holes for the med kit and tools.
*Wiring I'm making a custom wiring harness, and replacing the existing speaker wire since I'm driving the components off the amp. I'll be using all OEM connectors when I put the wiring harness together, so everything will be 100% plug and play, as well as reversible if I decide to change certain components.