Filling a 6600 Cu. ft. room

The question remains: Do you need to "fill that space" or do you need to have good sound in the portion of it used for serious listening?

Ok so in response to many comments.

My listening tastes are mostly Rock, Reggae/Dancehall, I love older bluesy rock. A little Hip-Hop, Rap, Funk, R&B and I plan on watching movies on it as well.

I want to have a um kind of blend between filling the space and dedicated listening area. More towards msolid listening space where I can still rock out while working around the house or cooking. Part of me would prefer to do a second system where I could do inwall speakers throughout the house for such purposes but the expense to be worthwhile wouldnt make sense to me as I want to build one fine system

As far as Subs go I have been looking into the Velodyne HGS15's and 18's as they have come down signifigantly in price and velodyne can fix the amps for me as there only 2 hours away

The most important thing to me is getting strings of a guitar right and being able to take a little bit of serious pounding. If its a reference I have found Equitech really puts out the sound im looking for. I know its just a conditioner but it really makes the chords just seem right.

Zu def's maybe 2 prs. Wired 4 sound 4 ch. amp

Hi,
Your needs are pretty specialized. I would gather few of us have experience with a 40x30x tall as a barn ceiling room. I recommend using the systems gallery part of Agon and reaching out to the other members with such a large room. A quick glance of these systems show speakers like VMPS, Apogee, Focal, etc. They might at least share their experiences with you. Filling up a barn-type structure sounds pretty daunting, just guessing, you will need at min two of your velodyne subs. At the Bay Area Audio Show this summer, Legacy (think it was their Whispers) filled up a good size ball room with their speakers. It sounded pretty good to me. Best of luck and enjoy the barn house, I always thought the designs can be very rustic cool.

I am currently in a 28X35 foot space with 14' ceilings.

The medium sized dipole monitors on stands (Cerious Too) are in 1 area a few feet from the walls, with dual woofers (cerious Bass) against the walls. Sitting about 12 feet away from the speaker, there is no problem hearing anyplace in the space. The sound travels. Bass may be a bit less in certain areas, but boosted to correct that would create too much bass in the prime listening spot. However you may want to look into a line array which drops only half of point sources as the distance doubles. Scaeana's are fantastic.

I would worry most about acoustic treatment as Reverberation will be a battle.