I plan on running to Fi Qs in a sealed enclosure, using the minimum recommended volume due to space constraints.  My power is a Zapco c2k 9.0 4ohm version.  I can run the amp bridged or in stereo, so that opens up both the dual 1ohm and dual 2ohm voice coil configs as options.  Since I intend to run sealed, I plan on ordering the high QTS option.   So here is the dilema: I noticed that the T/S parameters are different for both the D1 and D2 ohm cofigs, and I imagine that the high QTS option further changes the T/S parameters.  With that in mind, does anyone have any thoughts on which configuration would behave the best installed in the smallest recommended volume and using the high QTS option?