Klipsch Heresy iv...Your experience.

I owned Heresy's for years. They are a powerful little loudspeaker and the newer versions are even better. If you cross to two subwoofers at 90-100 Hz you can create and extremely efficient, powerful, low distortion system capable of achieving stressless, realistic levels in a moderate sized room. 

Wolf, the Heresy IV's woofer goes all the way up to 850 Hz. Middle C is 256 Hz to put that into perspective. So the woofer is carrying a very substantial part of the midrange. The woofer is also not a long excursion driver and even ported it only makes it down to 48 Hz. You probably like it on the floor better because it does improve the bass. They tilt it back to aim the speakers at about where your ears are supposed to be in a way mimicking putting them on stands. My point is getting the crossover up to 80-100 Hz will substantially clean up the midrange and add a lot of head room to the speaker as the woofer is it's weakest link. But you have to use a 2 way crossover to do this. Then you can also block the port which will tighten up everything further. You already have the subs and crossovers can be had inexpensively. Digital are the best if your preamp has digital outputs. 

Great speaker. Up on stands with two or more subwoofers and you have a very serious system. Very close to SOTA for point source. Wilson, YG and Magico included!