I think it depends upon the room (duh!) :-)
I started with mine about 3 feet from the rear wall and they didn't sound that great: the soundstage was attenuated and the bass was indistinct. I gradually inched them backward toward the rear wall, and at about 18" out, everything snapped into place. The room filled with music (in that distinctive "Ohm way"), the imaging came into focus and the bass response popped. I know that the CLS driver is designed so as to damp the sound that would normally come from the rear of the driver toward the wall, making near-wall placement much more feasible, but you still have to mess with them. But when they're placed properly, as Mapman says, "Bingo!", you know it. :-)
I started with mine about 3 feet from the rear wall and they didn't sound that great: the soundstage was attenuated and the bass was indistinct. I gradually inched them backward toward the rear wall, and at about 18" out, everything snapped into place. The room filled with music (in that distinctive "Ohm way"), the imaging came into focus and the bass response popped. I know that the CLS driver is designed so as to damp the sound that would normally come from the rear of the driver toward the wall, making near-wall placement much more feasible, but you still have to mess with them. But when they're placed properly, as Mapman says, "Bingo!", you know it. :-)