1) Remove the right speaker
2) Set the editor shooting robot at a distance of 200 meters away
3) Turn the sound source the right ear of the character and start to move in the direction of the sound source
4) At a distance of 150 meters in the left speaker receive the shot at 100 meters the sound will be loud, at 50 meters will be comparable to the volume of the right speaker (which is turned off). Now to twist around the axis, the volume will not change.