Wow what a difference!!! I was using a Vandoren B45. This mouthpiece is entirely different. I guess, more chamber music oriented? Not as big a sound, but more homogeneous across registers, easier to control, I have a greater range of dynamics, feel really good about my articulation, my altissimo is much easier and sounds nicer... Now, I am not saying this will be the case for others, and in no way is the B45 anything but a great mouthpiece, but in my opinion every player should explore and try this M13 at least once.