Here is context. I use more of the wedge concept by first lifting my shoulders to help expand what the chest muscle groups perform, then JUST BEFORE blowing and after taking that breath, I immediately RELAX the shoulders. Never play with tight shoulders. I then use pwhuuu breathing to exhale which works the best for me. That exhale option opens up my embouchure more than any technique I have ever used. It relies on using the upper muscles of the face that insert in the zygomatic arch (the bone below the eye). Look at it as the muscles that lead to a curve up smile - . This is apposed to the traditional embouchure that is a lateral smile that creates more of the traditional buzz. Ask anyone that has heard me play, the sound that comes out is powerful whether in the lead range or when playing pedal tones.