Need subwoofer recommendation


Don't know much about technical stuff, so I hope I'm saying this correctly. I was about to pull the trigger on the small HSU STF-1 sub for my Sansui integrated amp (20 wpc) when I found out that the HSU only has a low-pass crossover network. I was told by an HSU rep that I would need a high-pass filter to keep deeper bass out of the main speakers. That would entail my spending another $100. Rather the pony-up that amount, I thinking it would be better to simply get a sub that has both a low-pass & a high-pass network. Sooooo, some recommendations would be great. This is a secondary system for me, so I'm not looking to spend much more than $300, preferably less. I'm using book shelf speakers w/ 91 sensitivity rating.

Thanks
Johern
bluemando
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Hey Bob, I apprecitate that you made the effort to go to my threat at audiokarma. I'm going to have to give this some thought. Initially, I had thought that I could use a bit more bass for my KEF bookshelf speakers, which go down to 50 HZ (not bad really, but unfortunately the amp doesn't supply enough power at that HZ). I'm glad I posted here and a audiokarma because now I know what my options are in the real world. I had thought it was simply a matter of buying a HSU STF-1 sub, or the like, and all would be well in my world. I see it's not that easy. Thanks for your input... I'll take it to the drawing-board and see what I come up with.