I have a older HT subwoofer build (kappa sub build) in which I used a 12” car audio sub. I’m thinking about replacing that 12” with another car audio subwoofer that I have laying around, Sundown Audio SA-12 D4. I have been using a Oaudio bash plate amp but it sounds broken, very boomy and none of the controls make a difference when trying to adjust it. Instead of having the amp fixed I figured it’s best just to replace since it’s around 8yrs old. I was thinking about going with a pro amp, I know the ep2500\/4000 was a good match, but those seem discontinued. What is a good pro amp now days and what else do I need, external crossover? Thanks for the advice!