Speaker position

[Reffc]

To my mind this is one of those "if you have to ask you probably won't get it" questions.

The idea is for the output from the two speakers to meet in the middle and form an "image". If the speaker is baffled in the fashion you describe then the exact opposite would happen. The sound would be confined to the area of the speakers and would not form this "image".
Some speakers do it better than others (Kans) but this is probably the Holy Grail of HiFi.

Off axis performance is very important for imaging. By introducing baffles the sound will beam so the "sweet spot" will be very narrow indeed. You will still get reflected sound nat8808 as the baffles describe won't absorb, they'll act as a barrier but the sound energy will still be present within the room as diffused reflections. The brain takes the sound output from left and right channels and completes the illusion of music across a stage (and a stage with depth too) in front of you. If you can imagine the limitations of speakers which for arguments' sake only work on axis and the sound disappears at 1 degree off axis, it's not hard to understand that you will only hear music (in stereo) when the speakers are pointed directly at you. For any other condition, you will only hear reflected sounds (loads of phase distortion) and omni-directional bass notes. This is precisely why off-axis performance is so important. Peter Snell was very concerned about this as he knew that achieving the same off axis response over a wide area as on-axis meant that even reflected sounds, whilst having a degree of phase distortion, were less damaging to stereo imaging than having off axis performance at way lower output than on-axis. This is one reason why some Snell (and later Audionote) speakers can be used close to side walls.

[ballymenaman]

I've moved the speakers away from the corners. Big difference!