In case this might help, it is well established that reflected sounds should have at least a 10 millisecond delay from direct sounds to help clarity and minimize sonic smearing. Since sound travels at close to one foot per millisecond that makes calculations and set up easier.
This is why it is good to have the side wall reflection distance at least 10' longer than the direct distance from speaker to listener. Also, with dipole speakers it is best to create at least a 10 ms delay for the back wave. That can be done easily by placing the speakers at least 5' out from the front wall. So that should be the minimum, unless diffraction devices are added.
In my experience with Maggies and other dipoles the size of the room best determines if greater than 5' may be beneficial. Unfortunately there are so many variations in actual dimension, room construction materials, furnishings, and listener preferences that further specific recommendations are difficult. I would guess that 10' to 12' could work quite well but the only real answer is for you to try it and see.
This is why it is good to have the side wall reflection distance at least 10' longer than the direct distance from speaker to listener. Also, with dipole speakers it is best to create at least a 10 ms delay for the back wave. That can be done easily by placing the speakers at least 5' out from the front wall. So that should be the minimum, unless diffraction devices are added.
In my experience with Maggies and other dipoles the size of the room best determines if greater than 5' may be beneficial. Unfortunately there are so many variations in actual dimension, room construction materials, furnishings, and listener preferences that further specific recommendations are difficult. I would guess that 10' to 12' could work quite well but the only real answer is for you to try it and see.