Yet another benefit afforded by subs is that, should one elect to employ digital room correction (the DSPeaker Anti-Mode, for instance), the bass portion of the source signal can be digitized without the higher frequencies needing to be. This is easiest to achieve if one runs one set of ic's from the pre-amp to the sub(s), another from the pre to the amp powering the speakers. Not all pre-amps provide dual outputs up to the task, something to consider when choosing one's pre.