The speakers connections have to come from an amplifier with sound coming from it in the first place. Once connected to the unit the bass signal is then extracted from the signal and the rest of the signal sent to the main speakers. The KLH will not power the main speakers on it's own. The unit will only take the two main stereo channels, from an amplifier, the left and right then go to one set of inputs and they then come out of the other two outputs.
