I'm a little confused between the SW3s and SW3p, but I have the S version. It is passive, and the SWp apparently had an amp that matched it with custom crossovers and such to work together. The recommended amp is the SA-3, and the only one I see listed online is around $400. It outputs 250 watts, so quite a bit. Hoping to find something in the $200 range that would have enough power and have the ability to set crossover and such, since the sub is passive and has no onboard controls. Any thoughts?