Proper placement of the front left/right speakers is essential to achieve the smoothest frequency response, optimal stereo imaging and the most spacious, three-dimensional soundstage.
Stereo imaging and soundstage are affected by loudspeaker location and the listening position, relative to each other and room boundaries. Moving the loudspeakers away from room boundaries will tend to improve stereo imaging and spaciousness by attenuating and delaying boundary reflections, thus optimizing direct sound and helping to preserve spatial information in the recording.
SVS recommends starting with the front loudspeakers located 30-degrees to the left and right (i.e., a 60-degree total window) of the listening position. Toeing-in the loudspeakers 5-10 degrees can often improve imaging, however this is also a function of the distance from nearby boundaries and the ratio of direct-to-reflected sound, so experimentation with toe-in is recommended to obtain optimal results.