Also, the coax unit is impressive in its own right. The midrange is actually flat to 20kHz (without crossover).Thanks for sharing @prof
That is super impressive and suggests that true pistonic behavior occurs over the intended range despite the slow roll-off filters. Jim Thiel really knew how to make superb drivers!
And I did not know the CS2.7 has 10" woofers. That is contrary to other reports. Example here.
It looks like Thiel specified the frequency response down to 35 Hz, which is the same as the CS2.3 but a scotch higher than the CS2.4.

