Gene--Actually I replaced my trusty old Def Tech PF1800 with two Reference Supercubes and they are equidistant from the listening position. Then I thought--hey, I have a decent 18 inch sub that is still very functional, so why not place it in the back of the room since it has little resale value after 10 years and at this point, with lots of testing, it has not contributed any to the overall perceived LFE or with a RS sound level meter added a single dB of sound at the listening position. Obviously, when the SMS-1 arrives, I will have lots of testing to do and certainly will be willing to remove the PF1800 from the system. Thanks for your advice.
MikeSp