In my case I had to build a speaker box to match my 4 towers in a 5.1.4 Atmos set up. The factory is gone but I can still source parts and get repairs and get new parts. I am very old and my experience goes back to the late 60s. I am a stereo 2 channel guy to begin with but evolved into the surround sound beginning with quadraphonic. I have experimented with 2 seperate stereo systems in the beginning just because of economics. After years of mixing and matching I now am using all speakers the same. It sounds so much more connected and creates a seamless illusion. All the same drivers and same crossovers.http://https//www.dolby.com/us/en/technologies/dolby-atmos/dolby-atmos-home-theater-installation-guidelines.pdf
This should help significantly
This should help significantly