I'm running my system actively, using digital active crossovers and equalization via the HDMI output of my Mac Mini. It's definitely not high-end. The speaker arrangement is unorthodox. I'm using a matrix of 3 speakers for everything above 220Hz. These are all right next to each other, at 1 foot center to center distance, and all mounted on a single 2' x 4' board. The drivers are 10" midwoofers - open baffle, placed close to the back wall (because I have to) with absorber panels behind them. The 10" woofers go up to about 1200Hz, where they cross over to some horns, which are PT waveguide clones with JBL 2426H compression drivers placed directly above the midwoofers on the same baffle. There are capacitors on the horn drivers, which keep them safe and act as a pretty good EQ for the constant directivity waveguides, and keep amplifier hiss below audibility. 

My 3 speaker array, it achieves a wide soundstage through crosstalk reduction, which works better than I expected. The array mix is L-R, L+R, R-L. The idea was I wanted a center channel, and was wondering how much stereo effect I could retrieve with the side channels that didn't duplicate the center imaged sounds. I thought it might work with the speakers pretty close together, and it works really well! The reason I'm using the direct radiator 10" midwoofers is that I can't get a horn small enough to fit the 1 foot spacing. My calculations suggest that the wider spaced horns at 2' center to center spacing could still produce a wide stereo soundstage. I experimented with spacing the midwoofers futher apart than the tweeters, but that sounded odd. Center panned sounds did not seamlessly match side panned sounds. I'm wondering though if I could do a partial horn loading by placing all 3 woofers in a slot. So, they'd be loaded vertically but not horizontally. I've seen other manufacturers do things somewhat like this. I think Oswald Mills has a speaker that has wings going off the woofer that tilt to lightly load the woofer horizontally but not vertically. 

For the bass I have some corner horns, which are comprised of four cabinets stacked on top of each other. They're triangular shaped to fit in the corner, and use a split path folded 6' long horn. Each are driven by an 18" woofer. These are limited in the bottom end to about 30Hz, mostly due to the small backchamber size, according to hornresp simulations. They also have a problem with cancelation and resonance somewhere around 80hz. I don't fully understand this yet, but it seems to be a problem with the horn mouth being too narrow for the length of the horn, which has about a 6' path length. These bass horn stacks have a cabinet in the middle which contains a 2' long midbass horn that was designed to cover 200 to 2000Hz. This also has a coaxial tweeter horn right in the middle of it. These horns have problems, as you can imaging, with very uneven dispersion, with the midbass horn getting very narrow at 2000Hz, and then the tweeter starting out very wide above that. I did some testing to see what the midbass horn would do down in to the bass range, and of course it falls off dramatically below 200Hz. Interestingly, down at 80Hz it shows the same deep cancelation as the bass horns. Perhaps it's because of being right in between the bass horns. Perhaps I need to remove it from the stack and play it on its own to see if that's really the case. 

Anyway, my center array sounds much better in the mids and highs. The bass horns are flawed, but still quite beautiful and majestic. I prefer them to any non-horn loaded bass I've heard so far. With some EQ I've gotten them to measure flat down to 10hz according to REW. That means EQing the higher bass frequencies down a lot and then cranking up the gain for the associated channels on the receiver, which is just an old Denon 7.2 Surround receiver I got for practically nothing on craigslist. Since the horns are so efficient I can get some earth shaking bass and very loud playback without much amp power. I don't do that because on most music I'm perfectly happy if I can get a little below 30Hz before it starts to roll off, and I just feel better about not applying such drastic EQ.