I believe that I have what you describe.I was posting with Peter in some other threads in an off topic manner. I felt it worth a thread. I don't even know if this is possible with my gear.
I was at a friends with 2 large 8 foot wide by maybe 40 inch tall duel 15" horn woofers based upon Altec thestre design speakers. On top of them were 12 cell wood horns by Chela Audio. I have never been in front of any other stereo where the sound stage put me there on the stage with Simon and Garfunkel or Dylan.
It was without a doubt the most live stereo I ever heard. Amps were nothing special. Good but only $6k or so. Same for phono pre. Techniques SM12 with a Transfiguration Proteus. Yet that stereo made "live" better than any other I heard at a show or house.
I would love to get some semblance of what Howards system does. But I have no idea where to start. His stuff is in a room the size of a double garage. Next to no acoustic treatment's. Its just a totally immersive and enveloping sound stage. It surounds you. Mine is just there in front of me. I'm happy to get width. I don't get depth. To be honest, i never really hear any depth on any stereo. Sometimes a little. Usually from the speaker fronts back. Never from the sides of my head all the way back behind the speakers.
Is this really a big horn, big room trick. Is that why people love big horns. Or can it be done in a living room.
My system: MacMini Audirvana Studio > Chord Hugo MScaler > Chord DAVE DAC > Bakoon Amp 13R > Cube Audio Nenuphar Mini (F8 Neo) speakers.
My room: 383cm (12.56ft) wide x 526cm (17.26ft) long x 310cm (10.17ft) high.
Front of the speakers are 2.5ft from the wall.
The Cube Nenuphar are single full range driver speakers... hence no crossover. They are great speakers.