Subwoofer: should we even use them at all?

The conventional subwoofer is full of massive compromise in design -overly small cabinet, drivers with massive excursion, requiring huge power and room boundary reinforcement to produce bass. The excursion causes poor transient response extra distortion and reduction of bass detail. The massive power yields thermal compression due to voice coil heating. Having to place so sub can have room boundary reinforcement again causes issue with time arrival, integration etc. Great for high profit but not the best way to generate low frequencies. I myself prefer bass systems- towers, bass horns, IB bass etc over conventional cub sub.

I also tried numerous sub set ups and was never quite satisfied with the synergy to the main speakers. I'm sure there are Agon members much smarter than I that figure out the correct components, set up....
I went a different route. I had a pair of 3-way speakers built with Usher drivers. Uses one 8 inch woofer. Overall very happy with the speakers but found the bass to be a bit lite for some of the rock music I listen to.
I worked closely with the speaker builder tossing some ideas around.
I had him build a second pair of speakers - passive subs using the same 8 inch Usher woofer. The crossover has a very tapered slope and three cross over points. On the back side of the speaker I have three positive taps, one for each cross over point. I drive these speakers from the second set of preamp outs then through an Emotiva control freak (attenuator)- then to a separate Emotiva XPA-200 amplifer.

I love this set up since it provides close to the flexibility of a subwoofer set up but without synergy concerns. Main speakers run full range through a separate amp.
The passive sub cross over's slope is so gentle it ends up filling out the entire bass region, not just the lowest octave. When dialed in correctly the blend is seamless. So much better than any subwoofer set up I've used. The whole set up was cheaper versus the pricey Velodyne I purchased previous to this set up. Gives me flexibility for different source material too.

Every single tool has his limitations. Horn loudspeakers are not able to give a physical inimate image. Even when people would gave me 100 dollar each day I would not listen to this in my house.

You can go on and on about everything!

The limitation of Velodyne subwoofers is their response. They need to use lighter and faster material. Even that it can play loud and has a lot of dynamics. It is still not fast enough. With a few simple stereo test this comes to the surface quite easy.

"Horn loudspeakers are not able to give a physical inimate image. Even when people would gave me 100 dollar each day I would not listen to this in my house."

Bol1972,
I respect your experience and believe that you have achieved good system results through experimentation, but the above statement is certainly not true. I have owned many speakers, and horn speakers have provided me with a more intimate experience than any other type of speaker I have owned. I believe there are others reading this who will have a similar opinion.