A full range speaker?

William53b, in thinking about it I would to re-define my answer to reflect what I really believe. The full range that needs to be reproduced to create the "absolute sound" is 18 Hz to 20 kHz. However, no single speaker system should do this. Low bass requires a specific type of enclosure and location to perform well. Very low base also causes trouble with drivers that have to run up higher. Thus IMHO every system requires subwoofers. A main speaker should only be responsible for 40 Hz to 20 kHz at most on its own and 80 Hz to 20 kHz with subwoofers. So I would consider a loudspeaker that can do 40 Hz to 20 kHz to be full range. I have never heard a single driver do this successfully and my intuition says that you would be more likely to achieve satisfactory performance out of a well designed 2 way loudspeaker than any of these so called "full range" drivers 

@mijostyn

I agree. 40 Hz seems like a reasonable number for bass. And subs will always be needed to dig into the 20's. There are speakers that can go into the 20’s, but they are few and far between; and always rather large.

In a perfect world we would all be blessed with 14’x36’x12’ listening room, minimum, and the funds to fill that with our equipment. But until that day arrives I will have to be satisfied with trying to achieve that sound in a smaller room.

My friend is using the Lii Silver 10 on a four foot high baffle.....two feet wide....with four foot by one foot wings going straight back on the sides. He has measured 40hz flat in his room.....-5 at 30hz. The Silver 10 has a 28hz resonance. He added an ESS AMT on top using a copper foil cap above 10K......simply incredible sound. 98db efficiency. He soldered his speaker wires directly to the voice coil wires.....(he removed the binding posts on the speaker). This gives way better sound than going through a binding post.

Now he is going to add 2 15 inch woofers to each side.....he will bi-amp using a solid state amp and electronic xover for the woofs......and leave the 10 inch running full range or roll it off by using a smaller value of coupling cap in his tube amp. If the smaller value cap is a better cap then you have even better sound. By limiting the full range to above 100hz you will lower its distortion and increase its dynamic range. But, he has been listening to the 10 by itself for months and months now and is still Gobsmacked! The Lii drivers need at least 200 hours of hard playing to really loosen up. He has another system on the other side of the house and he can blast all day a new driver.

 the Lii Silver 10

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I had the LII Fast 8, the older model.
There was not even 1 thing I liked about that wide band
I quickly dumped it on ebay at 1/2 what i paid. 
I am experimenting with various Davidlouis, IMHO the DL's are the best bang wide band.
No I have not heard every AER/Voxativ
I did hear the Voxativ AC1A and  they were LESS THAN the cheap LII garbage. 
I have serious doubts to the performance of the AER/Voxativ.

I mentioned a serious implementation of the Lii Silver 10 and you talk about your time with a Fast 8 mounted with two screws in a POS box.

Sorry, I cannot take anything you say seriously. The way you post, how you talk, your system, your POS speaker test box, the system sound on your videos, etc......seems all very immature. You never heard the Fast 8......not in that horrible box......you need it burned in 200 hours, in the best box for it possible (right size, super dead and damped, great absorbing material inside, driver correctly mounted using brass screws torqued just right, etc.), binding posts on the driver bypassed, listened to on a more tweak stereo, etc......then you can say you heard the driver......same with any driver.