You can mount a Dipole speaker for rear surround just fine its all up to you. The comment about not being able to use a dipole is silly, dipole surrounds radiate from both sides not front rear.
can bipolar surround speaker on backwall with 5.1
I plan to build a 5.1 Home theater. However, the sidewalls of my living room, one side is window and the other is open space. So, I can't mount the dipolar speakers on the sidewalls. I am thinking to mount a pair of bipolar speakers (PSB imagine S) to the back wall, which is about 4 feet from the back of sofa. Does it work to create a surround evelopement? Or, do I need to change to uni-polar ones?