You're in band, you just warmed up and your chops are feeling great. You play B-Flat Chord Progressions- First, down the octave starting on low C- Then up the octave starting on middle C- Then, up the octave once more on upper C. But once you hit that last chord progression....nicely...people tend to turn around and give you an ugly look. Mostly the clarinet players right in front of me. I'm only in High School and can hit a double C on a Bach 3c mouthpiece. People hate me for it, it's one of the glories of being a trumpeter!