@rauliruegas, Raul, we built our systems over many years guided by our own preferences which vary to a large degree even though we agree on many aspects. On these issues I can tell you that you need to alter your opinion. I owned Apogee Divas for 6 years. A very enticing speaker that was seriously fragile and unreliable. Magnepans are much better from a durability standpoint and I think the 20.7 is even better sounding. The Scintillas could never reach realistic volume levels even with subwoofers. Apogee was right down the road from me in Massachusetts and I was in the factory on numerous occasions.
The Velodynes I owned were UDL 15s7's. The surround was foam and they all disintegrated. I have never heard a plate amp of any type perform anywhere near the level of a powerful class A or AB amp. These were the last active subs I ever and ever will use. Turn your system up to 90 dB playing any bass heavy number and put your hand on the subwoofer. That vibration you feel is distortion. In order for any subwoofer to be competitive it has to be a balanced force design, two identical drivers in phase directly opposed to each other. A 100 lb plate on top will not achieve the same results. Just wishful thinking. There are many subwoofer drivers with very low distortion specs. Just go to Parts express and have a look. The problem with subs is not the driver, it is the enclosure. Your servo system corrects the driver but not the enclosure. Of the commercial subs I have heard the Magicos are handily the best. I have not heard all the subwoofers out there. I have heard enough to know what designs have a chance of performing well. The problem with the Magicos for me is their size. I need to use four subs to form a line source and the Magicos are way to big. Fortunately, with digital subwoofer management and modern drivers you can make larger drivers perform wonderfully in small enclosures as long as you have enough power. I would love to use 15" drivers but again due to size I am limited to eight 12" drivers in four very special enclosures that have never been seen before. They are balanced force and stiffer than any enclosure in existence. They do not resonate at all. They are also pretty cool looking. At my current shop rate a pair will cost $50,000. That is how much work goes into them and they are passive so one would need to by amps and crossovers.
I think your speakers are a cool design that fails in two major ways. Dynamic drivers are much heavier that the air they move. It is like trying to run a motor without a load on it. It is very inefficient and due to their uncontrolled dispersion cause more difficulty with room acoustics. Your speakers have fractured dispersion. They are point source and omnidirectional in the bass and high frequencies and line source in the midrange which controls dispersion up and down but not to the sides. All this means that the amplitude response is going to vary with distance and you are still stuck with the acoustic problems of omnidirectional speakers.
My experience with ESLs goes back to 1978. I have owned five different versions, three of them hopelessly flawed because of bad electronics and fractured dispersion characteristics like your speakers, point source at lower frequencies and line source in the upper octaves. In order for an ESL to perform at it's best it has to be a full range dipole line source. This solidifies the image and makes them much more powerful. In order to function as full range line sources they have to extend from the floor to the ceiling, within a couple of inches. In order to produce realistic volumes with the extremely low distortion they are capable of they have to be mated to subwoofers and cross with steep curves no lower than 100 Hz. This requires digital crossovers. It can not be done with analog crossovers without significant damage to the sound. The beauty of Line source dipoles is that they do not radiate at all to the sides, up or down. They only send sound in a figure 8 pattern front and back. This make room acoustics a much more trivial problem. You only need absorption behind the speakers. The result is a very solid well defined image at all distances. There is no dynamic speaker that can match the transient response and detail of a proper ESL. The only advantage Dynamic speakers can have is size. They can be made much smaller. That is about it.
