...is it 2000sq ft or 20x50...that would be 1000sq ft...

In either case, it would actually be CUBIC feet that would be a starting point...need that ceiling height to calculate the volume...no, not that volume...and even that's not all to be taken into consideration...

Generally speaking, larger rooms require more powerful amplifiers to produce a given volume...yes, that volume or to be more correct, SPL(Sound Pressure Level)...

Bass frequencies require more power...and since the speakers may be required to push large amounts of air, smaller wall mounted units seem to be out...so larger units with perhaps custom or "industrial" types of bracketry may be required...

Then we have furnishings, or lack therof...furniture eats up power...lack of it builds a headache-machine...

You will probably be looking at multiple speakers and amplifiers or an office-type Muzak installation...but it's just going to be more of a sonic "wash"...don't expect any sort of "audiophile" quality set-up.

jimHJJ(...big and poorly shaped room to achieve that level of performance...multiple zones present their own problems...you may want to consider a smaller, dedicated listening area rather than "lighting up" the entire floorspace...although there may be solutions if you are willing to throw enough money at it...)