BoB- (I always really learn stuff from you and SH...)

>> If you draw a circle around the LP so that every point on that circle is equidistant to the LP with the mains, and use that line as the possible placement options for the sub (+/-) 1 or 2 feet, you have the start of accurate sub integration. <<

But, and this is why I have become so fanatical about phase *and* time alignment, this does not compensate for the phase delay introduce by the LPF (= low pass filter) of the pre/pro. Plus, this distance might result in nasty room interactions depending one where those equidistant points falls wrt the room boundaries.

Yes, still have the Vandersteen V2W. (Good memory!) I have been looking at the SVS PB2+, but I just can't get past how big and heavy it is. But ... it has flat freq response to 11 Hz. (I've measured mine, and I'm flat to 21 Hz, down 6 dB at 20 Hz.)