I have a philips Home theatre system(HTS5550) that i used as a 2.1 Hifi in my bedroom. I am not happy with the low end frequencies from the original passive sub and would like to know if i can connect and active subwoofer(any brand but most possible a polk 8inch woofer) to my existing system. There are no subwoofer pre-outs on my amplifier. Will it be possible to run a speaker cable from the existing subwoofer output channel on my home theatre amp to the subwoofer speaker input terminals and still get a better bass response. Bearing in mind that the speaker cable is carrying amplification and signal current. Will the active sub's internal circuitry balance out the amplification coming from the amp?