placement

You should place the sound between your eyes (as an opera singer might do) especially in the high register.  When singers speak of placement, they are generally referring to a sensation that the sound is ringing in the mask (the the front of the skull around the eyes). While voice scientists agree that one cannot be forcibly place sound, the sensation of mask resonance exists in singing and in flute playing. Placement in flute playing is often most helpful in the high register. That feeling you have right before you sneeze can help find the muscular activity that should be engaged when placing a sound. For a particularly beautiful soft sound in the low register, you can quietly send a consistent stream of air through your nose as if pronouncing [õ] as in the French word “ton”. Specifically, a beautiful and clear sound on a high E can be challenging. So a very precise combination of sound placement between the eyes, airflow toward the crown of the flute, well-proportioned air speed, and tongue position (as if pronouncing [ɛ̃] in the French word “brin”) will help.