Build my own speakers?

You are absolutely correct. Most speaker companies do just that. Purchase pretty good drivers and "stick um" in a MDF box. I would go for some space age cabinet material like Aluminum or Carbon Fiber. These and other composite materials will be the future of good speaker design. They hopefully will do away with the unwanted storage of the resonance that come hand in hand with MDF. Violins use plys of real wood for "wanted resonance". Vanderstein is experimenting with Carbon Fiber. Wilson benesch from England, not to be confused with Wilson Audio from Utah has been building speakers from Carbon Fiber for a number of years.
It seems like all I see in the industry is speaker companies coming out with new drivers made from all these different materials, ceramic, diamonds, titanium etc. They never really address the real problems of resonance. Planar speakers manage to eliminate lots of that because they just have a frame and not a storage box. I think that is why they
often sound so clear. I would not assume that these new drivers like the revelator are superior to the old, but tried and tested and user friendly, soft dome tweeters. Also I would start with a monitor speaker. Simple two way. Lots less cabinet to build. Someone once correctly stated "big speakers--big problems" The beauty there is you can build the monitor to sit on top of your bass drive when you get to that.
Good luck keep us informed.

My first project build will be made from MDF (many layers glued with a proprietary substance) and ordinary cement as a filler (don't ask also it is proprietary). My crossovers will be built and designed by me. Also I did extensive studies on property of wave forms at certain db levels (back lash etc.). I will keep the first modal for myself. If turns out good I will be-able to produce a set a month (due to I work full time now).

WHAT ARE YOU WILLING TO SPEND ON THE BEST FLOOR STANDERS IN THE WORLD?

A friend of mine is an avid DIY speaker builder. I've seem him go to extraordinary lengths to build the "best" speakers possible - special cabinets, exotic drivers, very detailed work on crossovers, sophisticated design software, hi-tech measuring devices, etc., etc.

I've also been to a DIY speaker convention where his ilk congregate. Although the stuff they do is very interesting I haven't heard anything that sounds all that great that they've built not mention look good. Sure some of the creations sound ok even pretty good but in comparision with manufacturer speakers, I wouldn't consider DIY unless one is just interested in it from a hobby and learning standpoint. I certainly learned a lot but never saw anything that competed with various speakers I've purchased and owned.

Hi Radrog,
I want mine to be a mini monitor that can fill a large room with the dynamics of a full scale symphony. I'll require 110db efficiency operating at a flat 10 ohms. Will that be a problem?

Regards,

Flat 10 ohms. Yes that a big problem unless you like one speaker. Then you are still looking at plus or minus 2 ohms. And a mini monitor to fill a large room. They usually consist of two way speaker. I never heard a mini monitor that sounded great. My thought is to build a 5 speaker system in the first order. Sorry but i'm lookin at 4 ohms with a swing of plus or minus 2.6875 ohms.