The road map

I decided to go with a cheaper woofer.
This project is an old one, and using an "old school" woofer seems to me more appropriate.
We can find thousands of reasons for the use of a different woofer, but at the end, read the first line...
So, this is it:

• It will be used only up to 300 Hz, where it will blend with a 10" midwoofer, loaded with a conical horn.
•  Then there will be a 1" driver loaded by a Tractrix horn for the frequencies from approx. 1000-1200 Hz up to the top, or at least where it can go!
•  In a second time, if needed, a supertweeter covering from 10-15kHz will be added.
•  At the beginning this system will be driven in single amplification mode, with a passive crossover, that has to be designed in a way that in a second time it will be possible to bi-amp woofer and mid-tw group. 
•  I will then go with multiamping if simple bi-amping will not give the best results.

Enough meat on this barbecue for now.