Hello there, I am a second year student in college and currently going for a degree in performance on the the trombone. And I needed some help with high notes. I can hit a high G above the staff most of the time and currently doing exercises to help increase that range. My problem is my throat. Whenever I get around the high E flat and F, my throat tightens up. This is especially noticeable when my lips get tired, and my range for a few hours is then only around the D above the staff. I was wondering if anyone had any warm ups, ideas, or ways to help me with my Problem.