For the columns my GC just built frames out of 2x4s. At what height should the surrounds be placed in them-at ear level when seated or higher? I was thinking of employing the same shelf idea in the columns that will be employed in the proscenium for L and R speakers. Also, what should be used to finish framing out the columns? Do they just get covered in sheetrock and then wrapped in GOM or do they just get wrapped without the sheetrock? Or is some other material more desirable for the front? Thanks.