FYI, OP. "Front wall" is the more common label for the wall behind the speakers.
What measurements from the rear wall?
Am looking for general measurements from my back wall. It seems that 3 feet from the back wall is pretty well accepted as the starting point.The question is where the measurement occurs: is it 3 feet from the rear of the speaker or the front? My speakers are Axiom M60s and are 14.5 inches front to back with rear firing ports. Do the ports figure in the distance to the wall? Fire away!