The most gorgeous 1.6khz & up I've heard from compression drivers came from TAD 2001s on Martinelli horns with a Pi xo which pulled the level waaaaay down to where my woofer lives, but then had the luxury of letting the upper end rise (where it naturally sinks), resulting in flat, extended, glorious highs. Oil caps in the xo everywhere I could didn't hurt any, either. The woodhorns can't be beat, IMHO.