05 WRX. What are the specs on the OEM radio and subwoofer (amps, watts, etc.)?

 

Don't have the exact numbers, but the true RMS output of the HU isn't that much, IIRC it has been measured at around 8W/ch. or so. The sub is advertised as being a "180W" or "200W" sub but it's also nowhere near that. I'd guess maybe 20-30W RMS at best.