I was at the junkyard the other day, and scored a stock under seat sub from a legacy a few days ago...I say "scored" because it cost me only $10, and I was looking to give the system in my old volvo ('82 project car) a bit of an improvement. By the looks of it, the sub looks like the same option that was available on my '12 WRX. With that said, does anyone know if it's possible to wire this to a non-stock system? The volvo currently has an Alpine CDA-9883, and four kenwood 4" speakers. I did keep the pigtail for reference, and I do plan on getting a pretty basic amp. I am just looking to have something decent in the car, but I am saving most of my money for other mods (e.g. turbocharging), hence the current setup. Oh, I also did grab the rear door speakers form the legacy, which look like they're 5" or 6." I haven't hooked those up yet, but I am guessing they will still be an improvement from the 4" speakers currently in the car.