Proper speaker placement is one of the most important parts of an audio system setup. According to Jim Smith, the author of Get Better Sound, the speaker placement alone has 50% impact on the overall system performance. My experience confirms that notion. The most important points of the placement are the distances between speakers, between speakers and the wall behind them and between speakers and the listener. One should not spare the distance to the back wall. I think that a minimum distance of 20 centimeters is necessary in order to have a proper soundstage portrayal and right tonal balance.