So yeah,
The stage with its smaller box and tougher driver
The Theater with its prolly more linear response, well, lower at least.

I already have boxes as big as the Theaters (a bit bigger actually, some 3ways I made using EV 15TRXB's) and honestly, the response goes REALLY low. I love the smooth bottom octave of these, but I'm not sure don't want another pair of 8cu ft enclosures...

The Stage 4 Pi's are an option... I'm just concerned that I'll loose some in the 25-40hz region.. my guess is that it has a pretty steep rolloff below 40 or so, where as the Theaters with the delta 15 have a much smoother rolloff

(All guessing and speculation)

Now, The question is quantitative. How much lower is the Stage at say 30Hz? anybody have a gander, measurements, or calculations (Wayne?)