I just want to make sure that I'm not missing something here. I have a Dolby Digital receiver and have set all of the speakers to "small". With my DD receiver, that means all frequencies at 90Hz or below are directed to the subwoofer. Although it's not specifically stated in my owners manual, I'm assuming that no frequencies higher than 90Hz are being directed to my subwoofer. So my question is; if only the subwoofer is handling the 90Hz- frequencies and none other, is there any reason to adjust the phase control on the SVS 20-39PC's amplifier? If not, does it matter where the phase control is set? 0? 90? 180? Thanks in advance for your response.