I too have a "Great Room" (30'wide 20'deep 14' ceiling) and I didn't want to run the wires all the way around the room to get them to my surroundsx4.
I was able to route the wires from 3 of the speakers to one corner, then up and onto a potshelf, there I cut a hole and installed a plate from Home Depot that had 3 pairs of banana/compression terminals (the left surr was near rack). Then ran a direct route in the attic to the wall that the rack was on, then fished them down to a plate that the builder had pre-wired for a security wire. Slapped on a matching plate and then I just needed 3' cables to the receiver. On the potshelf, I put in a bracket to screw the terminal plate to. I can't remember the name, but they are in the electrical area with other outlet boxes/flex conduit/etc. But these are shorter and just for this purpose. Oh, and they are orange. Can't miss them.