I would not put it on the floor, as the recommended location is above the surround speakers.. Also, the couch may take the sound effect away all together.

The reason for this thought....been there done that. I thought I could get away by not poking holes in the walls...but it just didnt create the effect. Mounting the speakers about 2-3 feet higher then the surrounds made the rear surround stand out in as far as effects from various sources.



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Denon 4308
M80x2,VP150,EP600,4xQS8