The subwoofer in that system is passive. The amplifier to drive it is in the dvd/receiver. You would have to buy an amp and probably an DAC to get an analog input for the amp if the TV has only optical audio out. If the TV has analog audio out then you would just need an amplifier. The sub is 4 ohms so about 25-50 watts mono would be sufficient power, Might be easier to just get a used self powered subwoofer.