A full range speaker?

There 
the 20hz-40hz, 
Ain't worth the trouble\
15khz,,, yeah like we can all identify these 15k-25k hz's when  struck by a  instrument,. 
I'm telling  ya, thats all bogus snakeoil
40hz is rock bottom, 
12khz is top of Mt Everst. 
above 12k is  for outer space astro-nuts.
Below 40hz is for cave dwellers.

Thankfully, you are not in charge of anything. Go on, keep throwing money at this trying to cobble together something without ANY clue as to what you are actually doing. It is great entertainment watching you fumble around cluelessly. If you had saved all of the money you have blown in the last couple of months flailing about, you could have actually bought something that sounds good, designed by someone that actually knows what they are doing. By all means though, carry on. 

I guess this is is just a hypothetical question since most rooms in your typical home could not handle "full range" orchestral reproduction. Bass waves are really big and even placing four bass traps in the corners of a typical room that would be given over to the audiophile in the house is not going to be adequate. It might be interesting to figure out what speaker frequency range works best in a typical home to reproduce as close as possible a full orchestra and what minimum size room would you need. Assume that the room can be treated for sound, but realistically that probably won't be the largest rooms in most homes, such as the living or family room, so four subwoofers would be out, maybe two at the most. How far down does one really need to go or for that matter, does one really need a pair of super tweeters to get satisfactory results?

full range drivers got very performance in mid bass 150-400 hz
to verify this I recommend all full range lovers use any equalizer and boost 300 hz  about 6db up and you see what you loose

sorry very bad performance