I forgot to mentionned, and complete my phrase... But now, I use the Toe-in just in front of my head, instead of behind. My speakers are 62 inches centre to centre. May be it is because of open space room and my ears. I have also notice, that when my chair is more on the right side, 1 foot of the centre, I heard a less fatigue music and little bit more high frequency , probably my ear and open space room. Thank you all.