Playing High Notes on the [Concert] Flute

In response to a question on Flute Forum regarding high notes going flat:

0. Have you had your flute checked out by a flute tech yet? If not, you might want to start with this. Eliminate issues with the flute first before trying to figure out if the player is the issue.

After doing 0, you might want to try the following by dynamics...

1. If you are playing at moderate dynamics, and only the high notes are flat as compared to the other notes, take note on HOW they go flat. If they start off IMMEDIATELY flat, it means your air stream speed isn't fast enough; in which case, you may need to push the air stream speed higher (while keeping as relaxed an embouchure as you can get away with). If they start out right, and then go flat, it means your embouchure isn't sustaining the right air stream speed, in which case more practice to strengthen the relevant muscles are in order. You might benefit from a lesson or two from a teacher to help with this; there is no shame in doing so.

2. If you are playing forte or louder, consider pushing a higher air stream speed -- [high] notes don't usually go flat at louder dynamics. There is a minimum air stream speed that can energise the correct harmonics for the high notes, but that is not necessarily musically correct. So, increase your air stream speed to tune it accordingly.

3. If you are playing piano or softer, close your jaw a little bit more to raise the air stream speed without cranking up the loudness.

Hope these can help solve your issue.