Hello All
We are building a home. Downstairs will be a multi-use area with a theater. Planning on a 5.2.4 Atmos system using the Invisa series speakers. Up front will be three SPS (L/C/R). The L & R will be in columns about 2' x 2', with a 9 foot ceiling. I'm thinking this is too large an area for optimal sound, so planning an constructing back boxes. Planning on using 1" foam insulation board and adding some sort of insulation inside(?). Thinking box size of 2 to 3 cubic feet.
Before starting this project, would love to hear feedback from this knowledgeable group.
Please let me know what you think?
Thanks

Probably no need to make back boxes for the SPS, a 2'x2' cavity with some insulation will be great (they are designed for use in a full 14x96x4 stud bay). Given the expected 80Hz crossover, the box (column) volume will be a non-issue.

Thanks for the response.
Looking at those numbers, it appears the "designed" cavity (14x4x96) is about 3 cubic feet. But in my open cavity (24x24x96) there will be about 32 cubic feet. That's over 10 times as much. Seems like that would change the sound from design.
? ? ?

Nothing will change above about two cubic feet.