Back in 1999 I had the idea to build a fully horn loaded speaker system with the bass being played by folded corner horns back in the corners and mid range (actually wide range) and super tweeter horns being well out into the room where they could image better. Obviously DSP was needed to correct the large distance difference between the various horn drivers. It was 2004 before I found a DSP unit which would do everything I needed at a price I could afford. That DSP was the initial commercial offering from DEQX. I built the system then. It was initially somewhat disappointing.
Over the next thirteen years I changed woofers, folded corner horns, midrange horn drivers, added horn super tweeters and went through six different changes of amplifiers as well as upgrading the DEQX. I programmed and reprogrammed and reprogrammed the DEQX over and over. Programming the DEQX is neither quick nor easy. I had the system sounding really good, but I always felt it could be better. Then in 2017 I engaged the services of a DEQX company approved DEQExpert, Larry Owens, Mr. Owens, a very smart man, connected his PC to my PC which was connected to the DEQX, and we communicated via a Skype call while he did speaker calibration and correction, time and phase correction, room correction and crossovers. If I remember correctly he took a total of about seven hours in two or three sessions to complete the process. Crossovers were set at 200Hz and 8 kHz with all roll offs being 96 dB/octave.
The speaker/amp system finally sounded as I had imagined it back in 1999. Modesty prevents me from using all the superlatives I feel my system deserves, but when fellow audiophiles come for a listen and say things such as, "that's the best I ever heard that song" I am immensely gratified.
Thus I have an active system with drivers and amplifiers of my own choosing with every element being easy to change. I think I have the best of both worlds.