The kit is an old philips 5.1 system, the speakers all work fine. The receiver was starting to have problems, so we purchased a replacement stand alone receiver from Denon (https://tinyurl.com/y7g87qzt). The old receiver had the sub amp built in, and this one does not appear to (the sub output looks to be RCA?). The product literature isn't super thorough and I'm not sure what the best course of action would be. Looking for some guidance towards the cheapest and easiest solution. As I understand it, there are two paths: get a plate amp for the subwoofer I have, or purchase a powered subwoofer compatible with the Denon. Is one of these ways easier/better? Any product recommendations? Is there another option I haven't considered? Any advice/guidance would be appreciated.