I didn't really know whether to put this in Mastering or Mixing, then I decided it had more to do with touching up rather than initial construction. I recently read some papers on how humans tell the direction from which different sounds come from - from slight delays between left and right ears, the timbre, relative perceived volume levels, etc. There was this part that mentioned bass frequencies travelling right through the head and being perceived by both ears, making it difficult to tell where those sounds are coming from. When listening to my mixes through the headphones, I found that the floor tom sounded unnatural when panned towards the side, whereas when coming through the monitors, it sounded pretty decent... Is the effect mentioned above factoring into this phenomena? When mastering and playing with the stereo image, is this usually taken into consideration? Would it make the mix more "realistic" and "spaced proportionally" when listened to through headphones if the bass ranges were more equal on both sides? Hope the question makes sense.