Ah, now getting somewhere.
Yes, if you want optimum speaker positioning it is going to be in a room where music is primary and you sit and listen to the music. For background listening, nothing is very important.
The methods of using microphone and instruments sound intriguing, as I suspected all along that this could be done somehow. Perhaps some more writing to detail the procedure/process could be helpful.
FWIW, my room is 13 x 14 x 10. The room is a bit irregular with a bay window on one side and a fireplace in the middle of the back wall sticking out in to the room. I sit to the right of the fireplace, pretty much in line with the right speaker. My perspective is like I am sitting in symphony hall in a seat on the right side aisle. I set my speakers as described in my post following the instructions exactly. The area of sweet listening is pretty large, even in this small room.