The frequency response data on the Pt2 indicates very good performance in the horizontal plane--much like a 0.75 inch diameter dome in that it starts to fall-off versus frequency above 10,000 Hz for 45 degrees and beyond off axis. But the vertical axis performance can fool you in that the roll-off is minimal at 2000 Hz but if you look at the off axis angles and increasing frequency you have slopes falling off at fast rates beyond even small angles off axis.

The important issue is that the total power that you hear is a combination of both horizonal and vertical axis performance. Hence, any array gain addition versus frequency of the Pt2 is much less than one would measure with cone or dome drivers.

Jim