I'm in a converted garage space - two car garage. finished and carpeted. I think it is 25'x25'x8' ceilings.
The right side wall has two abutments; a mechanical works closet, and, rear of fireplace chimney (the side of the chimney structure that you typically see on the side of the house; keeps the music room way too warm!). The left wall has a small window, and the rear wall its pretty much empty, except for an extra bed tucked into a corner.
I have a chaise style couch set up across the front arrays.
From the middle part of the couch, you are center to my Soliloquy 6.3 pair and Plinius 8200 AB Integrated
From the right side chaise, you get centered to my daily drivers, Bozaks b302a Urbans and a chip amp fed by a Pioneer DVD-A deck -> Schitt DAC
The hard right wall of the room, at the front right corner, I have a mono corner speaker, GE A1-400 coaxial in original cabinets (a pair, but only one used. the other is used as a speaker stand for the top functioning speaker). That system is driven by Audrey, my retro-mod mono console.