Hi, I'm currently going through a complete embouchure change. I used to play very off center and with barely any top lip - I am changing to a center position with an equal amount of top and bottom lip. I have made good progress and after losing my high register I can now play up to a G above the stave. I have however lost my lower register - can anyone explain why this is and suggest any exercises I can do to build it up again? Any suggestions of exercises to improve tone and/or increase my high register to where it used to be would also be greatly appreciated. Thanks!